Health and the environment

PUBLIC HEALTH IN EUROP~ 8 REGIO AL OFFICE FOR EUROPE World Health Organization Copenhagen 1977 l>C &.. I PUBLIC HEALTH IN EUROPE NO. 8 Health and the Environment CORRIGENDA Page 2, line 43 delete insert introduction approaches introduction of harmonized approaches Page 24, line 18 delete insert emphasized overemphasized Page 55, lines 8 and 9 delete insert in the forecasting forecasts -qJ>51t PUBLIC HEALTH IN EUROPE 8 Health and the Environment ~,~, . 'i tt ,,~ -/JI REGIONAL OFFICE FOR EUROPE ~~ World Health Organization Copenhagen 1977 Data and short exce rpts from Public Health in EUI'ope may be reproduced provided that the s ource is acknowledged. For rights of rep roduction or translation of articles in toto appl ication should be made to the WHO Regional Office for Europe , Scherfi gsvej 8, 2100 Copenhagen 0, Denmark. The Office welcomes such applications. The designations employed and the presentation of the mate r i al in this document do not imply the expression of any opinion whatsoever on the part of the Secretariat of the World Health Organization concerning the legal status of any country, t e rritory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. Authors alone are responsible for the views expressed in Public Health in EUI'ope . ii Reissued under ISBN: 9789289023740 (print) in 2025. Originally published under ISBN-10: 9290201274. ISBN 92 9020 127 4 ISSN 0300-4880 © World Health Organization 1977 CONTENTS Introduction - J.I. Waddington 1 1. The development of rural water supplies and sanitation, with particular reference to developing countries - D. Konchady 5 WHO and the forthcoming water decade. 13 2. Water supply and wastes removal in rapidly developing areas - G. Watters . . . . . . 14 3. Housing hygiene in Europe - E. Giroult 26 4. Design and implementation of comprehensive environmental pollution control projects - P.H.A. Gilad . . . . 31 5. An approach to environmental quality management in the context of regional planning in the province of Katowice, Poland - C. Ferullo . . . . . . . . . . 55 6. Pollution control in a large river basin T. Murawski 69 7. Planning reductions in the emission of pollutants from industrial sources - R. Bouscaren ..... 81 8. Community noise study in the Athens metropolitan area - J . S. Sirnandonis . . . . . . . . . 87 9. Food control - B. Blomberg and A. Wahba 104 10. Tourism and sanitation in Europe - E. Giroult 110 11. Health hazards associated with introducing new chemicals in industry: prevention and control - S. Forssman . . . . 115 12. Permissible levels of toxic substances - V.J. Krichagin 123 13. Epidemiological studies of air pollution health effects R. van der Lende . . . . . . . . . . 140 14. Manpower requirements in environmental health fields in Europe - S. Arceivala . . . . . . . . . . . . . . 148 iii INTRODUCTION J.I. Waddington1 This issue of "PubZic HeaZth in Europe seeks to highlight some environ- mental health problems of current concern and to describe some of the acti- vities of the Regional Office in this field. Industrialization proceeded much earlier in many parts of the Europ ean Region than in most other parts of the world. The drift to the towns still continues and almost everywhere rural populations a re decreasing and urban areas expanding. There is considerable disproportion in many coun- tries between the basic sanitation services available in towns compared with the countryside. Whereas most cities in the Re gion have adequate water supplies of good quality and an increasing proportion have also satisfac- tory disposal facilities for liquid and solid wastes, there are still many rural areas where such services are rudimentary. At the United Nations Water Conference in Mar de Plata, Argentina, in March 1977 it was recommended that priority should be given to the pro- v is ion of safe water supply and sanitation services for all by the year 1990, and the period 1980-90 was designated the "International Water Supply and Sanitation Decade". The Thirtieth World Health Assembly resolved in May 1977 that WHO should help towards the achievement of this targe t. Within the European Re gion there will be special emphasis on the needs of smaller communities in order to ensure complete population coverage, and also on the problems of towns and cities, particularly those in coas tal areas, where wastewater disposal facilities are still inadequate. It is clear that much of the vast expenditure to be committed to this work will be wasted unless the construction of new water supply and sanitation schemes is accompanied by acceptance of the need to achieve a continuing high stan- dard of operation and maintenance. The last decade has been characterized by unprecedented interest in conservation of the environment, not least within the European Region. There has been growing concern about the impact of new industrial processes, new chemicals , new modes of energy production and changed patterns of living on the health and wellbeing of man. Fears are frequently expressed about the adverse influence of man's activities on other life forms as a result of changing land use and environmental pollution. 1 Chief, Promotion of Environmental Health, WHO Regional Office for Europe. 1 In many countries in the Region environmental health priorities are shifting towards the complex problems involving environmental conditions which constitute potential hazards to human health in the air, in water, or in the food chain. Consideration must be given to dangers to the general population and also to special high risk groups, either as a result of their occupation or in their place of residence . The scientific basis on which the effects of environmental changes can be assessed is a complex one and there is a need to improve, for example, the techniques of predictive epidemiology and of risk assessment for new chemicals and other hazards. There is a need to more adequately define both the procedures which should be followed before new chemicals are accepted and the controls which might be required in respect of their use and disposal. Improved techniques are also required for the assessment of factors bearing on social costs and benefits relating to the introduc- tion of new processes and chemicals. In some countries attempts have been made to study damage costs of pollution, but these are particularly diffi- cult to quantify in terms of human health and wellbeing . There is a growing need to develop information and warning systems on the effects of environmental hazards on health and to increase the scope and effectiveness of toxicological data banks. In view of the rapid intro- duction of new chemicals, it is important that information on health effects should be disseminated as quickly as possible. Environmental impact assess- ments are now becoming recognized as an important requirement before indus- trial or other development takes place and it is impo~tant that each such statement should fully take into account the effects on human health and wellbeing. It has been generally acknowledged during the last 10 years that it is necessary to comprehensively monitor the various aspects of environmental changes. Such has been the extent of these programmes that there is now perhaps a danger of an over-emphasis on monitoring and the acquisition of data compared with the efforts which need to be devoted to prevention and control measures. It is important that monitoring procedures are harmon- ized and WHO is cooperating with the United Nations Environment Programme (UNEP) in several aspects of the Global Environmental Monitoring System. Many pollution problems within the Region are of an international nature and it is therefore important that surveillance and evaluation procedures are compatible. The Regional Office is cooperating with Member States in relation to water pollution problems being experienced along the River Danube and by countries bordering the Mediterranean. It is also developing a series of manuals relating to aspects of water and air pollution, solid waste management and non-ionizing radiation protection, which it is hoped will assist the introduction approaches. During the last few years the European Office has been involved in a number of UNDP-assisted national projects concerning environmental control, for example, the establishment of a research and development centre in Silesia, and an industrial toxicology centre at Lodz, Poland, various air 2 and water pollution control problems in Romania and Spain and a comprehen- sive programme for pollution control in the metropolitan area of Athens, including air , water, solid wastes and noise. Water supply and sanitation projects have been executed in Algeria, Malta, Morocco, Turkey and Yugoslavia and a cooperative programme with the Government of Portugal commenced in the second half of 1977. The work which the Regional Office for Europe has carried out in these countries has pointed to the need for establishing international networks of cooperating institutions, so that the best use can be made of resources when tackling problems shared by more than one Member State. In some cases, by virtue of the size and diversity of the Region, problems exper- ienced in one place may be quite dissimilar from those elsewhere. This is clearly shown in the case of the Mediterranean, where the public health problems of coastal pollution differ in some respects from those experienced along the shores of north-western Europe, whereas there are common problems in this field experienced by all the Mediterranean coastal states and there- fore there is a community interest among them. The environmental pollu- tion activities carried out by WHO will seek to facilitate such cooperation. The Regional Office now has considerable experience in the planning and implementation of large-scale environmental pollution projects which can be carried out in cooperation with Member States within a resonable budget and on a limited scale to achieve optimum results and influence. It is hoped that it will be possible to make this experience available out- side the Region. To an increasing extent such projects are designed to facilitate the planning and execution of broad national environmental health policies within the context of overall economic and social develop- ment. A feature of the last few decades has been the great increase :jJl inter- national travel, both in relation to work and tourism. Such mass move- ments result in both migrating and resident populations being exposed to hazards against which they have not developed defences. In addition, there are special hygiene problems related to transportation itself and the Regional Office recently organized a meeting concerning food hygiene in the air transport industry. In many countries a decreasing proportion of the total meals consumed are prepared and eaten at home and a forthcoming series of working groups will cover food safety in relation to various forms of mass catering (res- taurants, institutions, open-air festivals, etc.). In spite of improve- ments in European public health services and of improved methods for food preparation and storage, there is still a substantial and perhaps increas- ing incidence of food contamination in public places. In the field of environmental management coordination between institu- tions and disciplines is particularly important. Unfortunately, there has so far been considerable fragmentation in legislation, administration, research and abatement and there has not always been sufficient emphasis 3 on human health in decision making concerning environmental problems . Progress towards rational administration has so far been generally disap- pointing within the European Region, with responsibility often being divi- ded among several agencies. However, health ministries often lack the authority and resources to assume a prominent role and to promote national programmes. The need to strengthen environmental services is closely linked with training of the necessary personnel. A great many specialists are already at work in various fields of environmental management, but there has per- haps been insufficient emphasis on interdisciplinary training . Effective management requires active cooperation among biologists, chemists, physi- cians, economists, engineers, lawyers and planners. Manpower needs are not, of course, confined to the professional level and increased attention must be given to training of personnel, for example, for the operation of treatment plants and other control facilities. The environmental health programme of the Regional Office has of necessity to cover an extremely wide range including water supply and waste disposal, environmental pollu- tion control, food safety, and occupational health. It embraces legisla- tive, administrative, and technical aspects and also the development of trained manpower. The articles which follow provide a cross-section of some of these fields of interest. It is fitting that thanks should be expressed to all contributors and in particular to Mr D.H.A. Price, Consultant to the Regional Office for Europe, who gave much valuable assistance in the pre- paration of this issue of Public Hea l t h i n Europe . 4 1. .._ &,-1!' cl' ~ t, 't{,fr c. '-'(1/_', • 1-'--- ' ut1.L r I ( l tf { (.__i,.M. I' ,Ll,,(... rr< THE DEVELOPMENT OF RURAL WATER SUPPLIES Al.'ID SANITATION, WITH PARTICULAR REFERENCE TO DEVELOPING COUNTRIES D. Konchady 1 In the majority of the countries in the European Region of the World Health Organization the socioeconomic evolution accompanying urbanization and industrialization has either brought about a diminution in the disper- sion of rural settlements or has generated a level of rural economy capable of fostering the infrastructural services. The abili ty of a society to pay for its needs and the application of knowledge about· the transmission of wate r-borne and waste-borne diseases have made it possible in these places to provide safe water on demand and to remove wastes via individual or public sanitary disposal systems. This, however, is not the case for the majority of the rural populations in the developing countries of the Region, such as Algeria, Morocco, and Turkey. The developing countries inherit a number of burdens, including a poor economy, a population explosion, and inadequate resources of money, materials, and trained manpower, which are serious obstacles to their development. In this situation, rural areas fail to share fully in the national, social, and economic development plans; they remain underprivileged and therefore neglected. The absence or scarcity of safe water supplies and the use of unsafe water sources undermine rural health; lack of sanitation facilities raises morbidity and mortality rates, which, in turn, depress economic pro- ductivity and curtail social development; this vicious cycle continues in- definitely and migration from rural to urban areas is a common feature. WATER SUPPLY, SANITATION, AND DISEASE Water plays a key role in the transmission of certain diseases. These can be classified as follows: water-borne infections, e.g., cholera, typhoid, diarrhoeal diseases water-related diseases, e.g., filariasis, malaria, schistosomiasis. The relationship between water and disease is complex. In rural areas not only is the purity or safety of water important, the amount of water available, its accessibility, and its acceptability are also factors in the origin and spread of disease. From the public health point of view, no 1 Sanitary Engineer, WHO Environmental Sanitation project, Turkey. 5 single measure can do more to improve the health and wellbeing of the rural dweller as the provision of an ample supply of safe water.l Provi- sion of sanitary facilities for the disposal of human wastes reinforces the health benefits gained through the provision of safe water. THE RURAL WATER SUPPLY AND SANITATION PROBLEM The term "rural" is defined generally by the criteria of an upper limit of population (3 000, 5 000, or 10 000) assuming that the occupa- tional patterns and residential characteristics of such communities are clearly distinguished from those of urban communities. Exceptions to these criteria are certain to arise and every country needs to establish and define its own criteria when setting up rural development programmes. Generally speaking, the population of the rural sector in the develop- ing countries is larger than that of the urban sector, and much of that population is without access to safe and adequate water. The unserved population depends on sources of water that may be subject to risks of con- tamination or may be qualitatively damaging to health. In certain cases, owing to unfavourable hydrogeological conditions, scarcity of water is a chronic problem. In epidemiological terms, illness resulting from the lack of safe water and sanitation is much more widespread than is apparent from records of vital statistics owing to deficiencies in the reporting or recording of cases. Major constraints on the rural water supply programme in many coun- tries are lack of information on the nature, scope, and size of the problem and of a long-range plan with defined targets and means of financing, both internal and external. Another important constraint is deficiency of the institutional framework. In many instances programme implementation is entrusted to several different agencies and operation and maintenance of completed facilities does not receive proper attention. In some others, the organizational structure has not yet built up the managerial and ad- ministrative skills required to promote progressive mobilization of finan- cial, material, and manpower resources. External assistance has sometimes been used in isolated demonstration projects without any follow-up total plan of action. In all cases, local community motivation and participa- tion are prerequisites, without which many rural programmes often fail to produce results. 1 For definitions of "safe water" and other terms used here, see Pineo, C.S. & Subrahmanyam, D.V. Community water supply and excreta dis- posal situations in the developing countries. Geneva, World Health Organi- zation, 1975 (WHO Offset Publication No. 15). 6 The global target for the United Nations Second Development Decade, as recommended by WHO and accepted by member countries, is to provide adequate safe water for 25% of the rural population by 1980 (50% in member countries of the Pan American Health Organization). 1 With regard to sanitary means of excreta disposal or installation of sewerage systems in rural areas, PARO member countries have adopted certain targets - namely, 50% of the rural population to be served adequately or, as a minimum, to reduce by 30% the number of inhabitants not possessing adequate facilities. Almost all the developing countries in the WHO European Region are expected to meet the above target for rural water supplies but the increas- ing demands of the rural population call for better services, e.g., more house connexions than public standpipes. Installation and maintenance of such services warrant institutional reforms. At present, less than 10% of the population in rural areas of the developing countries of the Region have adequate facilities for excreta disposal and the present rate of pro- gress needs to be accelerated. PLANNING OF RURAL WATER SUPPLY PROGRAMMES Planning Strategy Setting targets and priorities The goals of rural development extend beyond any particular sector; they include improved economy together with adequate shelter, food, educa- tion, and health. These goals are interdependent and mutually reinforcing. Improved water supply and sanitation form the spearhead of any health pro- gramme in the rural sector. The basic requirements in planning strategy, therefore, are to define national targets for the programme and obtain re- cognition at the policy-making levels of government of the benefits to be derived from water supply and sanitation programmes. In other words, in- vestments in the rural sector represent overhead capital chargeable to the national budget. 1 The Pan American Health Organization (PARO) comprises the Pan Ameri- can Sanitary Conference, the Directing Council, and the Pan American Sanitary Bureau (PASB). The Pan American Sanitary Conference (or the Directing Council in those years when the Conference does not meet), serves as WHO's Regional Committee for the Americas, and PASB as WHO's Regional Office for the Americas. 7 Framework of resources and finance In order to attain stipulated targets, an effective organization must assume responsibility for the progrannne, and it should be provided with the institutional support and financial resources required for progrannne imple- mentation. Manpower resources determine the quality and rate of implemen- tation of a programme as well as effective management of the completed con- structions or installations. Mobilization of financial resources, both internal and external, are vital for sustaining and promoting a long-term national plan. Inadequate material resources may be a constraint on the progress of work if supplies are not taken into account in planning the programme. On the other hand, economics of scale accrue when programmes are undertaken on a national level and are planned in conjunction with other sectoral development programmes. Plan of Action Survey of the situation A country-wide survey of service coverage - namely, populations having reasonable access to safe water and those remaining to be served - should be conducted by national experts with external assistance if needed. This overall assessment and identification of the scope and magnitude of the long- term programme should allow implementation of the programme in a phased manner through systematic planning. Institutional framework One of the most important programme requirements is establishment of an organization with the manpower resources necessary for the planning, installation, operation, and maintenance of water supply and sanitation systems. Few, if any, of the developing countries are self-sufficient in the manpower skills and training facilities required for the technical, administrative, and managerial tasks involved. A pressing priority is the training of national staff of all grades to ensure that there are adequate personnel to plan, design, construct, operate, and maintain the various constructions or installations. Prevailing patterns of organizational structure differ widely. A ministry - public works, agriculture, health, rural affairs, for example - usually handles this progrannne as one component of its activities but in some instances more than one ministry is actively involved in the programme. It is sound practice to make a single ministry or agency responsible for the programme and to employ professional and subprofessional personnel to prepare simple and economical system designs compatible with good sanitary standards. Short-term planning The situation survey referred to above will help in the preparation of a master plan for a country-wide solution of rural water supply and 8 sanitation problems . The master plan does not involve advanced prepara- tion of system designs but pe rmits long-term planning, which, in turn, i s implemente d t h rough a se r ies of short-term plans . Sho r t-term plans are formulated according to a priority rating of com- munities, determined on the basis of answers to the following quest i ons: (1) degree of scarcity of drinking-water; (2) number of villages endemic for enteric diseases; (3) total population of villages to be served; (4) contributions to be made by beneficiaries in terms of land, funds, and other r esources; (5) per caput cos t of the project; (6) cooperation between villages (within a village and between villages in group schemes); (7) collaboration of villagers with local administration. In the initial stages of investment in a programme, consideration should be given to choice of engineering designs and operations that will result in maximum cost/effectiveness and population coverage (this point is discussed also in the following article, seep. 14) . Water rights and water allocation Allocation of water constitutes a major problem in the performance of water supply activities. Existing legislation on water rights should confer authority for allocation of water to a government agency, possibly to one that is not using water but preferably to a water resources board or authority . Othe rwise, alternative arrangements for allocation of water through special connnittees representing all community interests may have to be formed to arbitrate in disputes. Disputes concerning water allocation often arise when water from a single source is shared by a group of villages . The attitude of local administrations and their judicious exercise of authority are extremely important in settling disputes. Feasibility appraisals Feasibility appraisal of a short-term plan involves assessment of financial, manpower, and material requirements and the means of meeting them. Financial resources Mobilization of financial resources for the capital cost of construc- tion of rural water supplies, the cost for operation, management, and 9 related manpower, the capital cost of expanding local production and organizing new manufacture of needed materials, and the costs of promoting an effective rural sanitation programme should all be considered in long- term planning of the total programme. Insufficient internal financial resource is by far the most usual obstacle to progress. However, it has been demonstrated in many countries that once a national policy is adopted, internal financial arrangements can be made to generate the funds required for starting and developing a programme. The use of revolving funds, i.e., a fund that is continuously replenished as it is used, either through further appropriations or income generated by the activity that it finances, has been successful in many countries. At the outset, in many developing countries the government provides funds to cover all costs, including operation and maintenance, but with increasing demands for funds this method of financing becomes a serious drain on government resources. Absence of community participation and involvement makes it difficult to provide funds for expansion of the schemes and for the national programme. Therefore, participation of com- munities in paying the cost of operation and maintenance should generally be a minimum requirement for installation of a water supply system. The ultimate objective should be to generate revenues by direct user charges; these should include interest and amortization of capital cost, operating and maintenance costs, together with a charge to cover future expansion. The initial contribution to the revolving fund is usually made through a government grant. Loans with liberal interest rates and deferred re- payment terms are also possible. Generally, it is many years before the fund becomes self-maintaining and, until then, government allocations from general tax revenues are required. As regards external assistance, a number of international agencies, including the United Nations Development Programme (UNDP), WHO, and the International Bank for Reconstruction and Development (World Bank), participate in promoting development of rural water supplies. Pre-investment planning is often undertaken by WHO. Other important considerations One of the most challenging tasks in the development of rural water supplies is to adapt existing technology to meet the needs of rural com- munities and to make innovations to suit local conditions. The main cri- terion for selecting a system should be ability of the community to support the system in all respects. Factors that have a major bearing on the cost of the system, as well as on that of operation and maintenance, relate to design criteria. In adopting design criteria, there should be flexi- bility to make modifications in accordance with local conditions. Although standardization of design makes for economy, there is always a risk of arresting innovation. There is also urgent need to exchange information on available technology that is undergoing continual adaptation with a view 10 to reducing costs and facilitating operation and maintenance. The WHO collaborating centres for water supply1 alrea dy support dissemination of such informat ion . Role of the health department . Rural wate r supply and sanitation form an integral part of the total environmental health progra=e and irres- pe ct ive of which agencies are responsible for the activities, the health department has a key role to play in programme plannin g, selection of pri- ority areas, choice of types of rural sanitary privy, organization of health education, and programme evaluation. Water quality. International standards for drinking-water qual:lty2 or similar guidelines are followed by most countries. In general, selec- tion of sources shoul d be based on water quality, s ources requiring least treatment being preferred . Monitoring and surveillance of rural water supplies, except where piped systems exist, is not f easible, and it is necessary to rely on sanitary protection of water sources and quality con- trol of supplies , togethe r with simple dis infection procedures when ne ces- s ary . Competent operation and efficient maintenance are essential for the success of any national rural water supply programme . As s t ated earlier, communities may not generate sufficient revenue to meet interest payments and amortiza tion of capital costs, but as a rule they should pay for opera- tion and maintenance. Provision of house connexions, where feasible, and levying appropriate tariffs is one way of generating some income. For effective maintenance of pumping and other equipment in small communities, one solution might be to form a task fo rce of skilled men, expenditure being paid by the water supply agency and reimbursed to the agency by the corrrrnunities . Alternatively, the government agency may accept responsibility for operation and maintenance, charging the cost to the communities on a pro-rata basis or partly to the corrnnunities and partly to the government . Community participation. One of the key elements of a rural water supply progranmle is health education of the community t o stimulate local invo lvement and sharing of costs with the motivation to benefit from im- proved personal and cormnunity hygiene. Health education is best provided by health workers, especially sanitarians and sanitary engineers trained in health education methodology. Audiovisual methods of education are useful bu t depend on the quality of the media. Schools are an obvious channel for community health education . 1 For a list of these collaborating centres, see WHO Official Records, No. 22 9, 1976 (The work of WHO in 1975: annual report of the Director- General ), Annex 5, p. 347. 2 International standards for drinking-water quality, 3rd ed., Geneva, Worl d Health Organization, 1971. 11 Rural sanitation. Maximum health benefits are obtained when rural water supply and excreta disposal are undertaken simultaneously. Experience shows that the improvement resulting from the provision of safe water sup- plies coupled with community education by health workers leads to acceptance of an excreta disposal programme if such a programme is conceived and launched in time. Therefore, efforts should be made to obtain acceptance for the simultaneous installation of water supply and waste disposal systems. If, for any reason, there is reluctance on the part of the community, waste dispo- sal facilities should be introduced as soon as possible after the provision of a safe water supply. 12 WHO AND THE FORTHCOMING WATER DECADE Following the United Nations Water Conference which was held at Mar del Plata, Argentina, in March 1977, the Thirtieth World Health Assembly, meeting in Geneva in May 1977, adopted a resolu- tion (Resolution WHA30.33) urging Member States to participate in an International Drinking Water and Sanitation Decade during the period 1980-90 which is to have the objective of providing the en- tire global population with safe water supplies and hygienic waste disposal systems. As a first stage, the Regional Office for Europe of WHO is carrying out a rapid assessment of the present population coverage of water supply and sanitation services within the Re gion. This work is expected to be completed by the end of 1978. Most of the larger communities within the Region have adequate drinking water supplies, and most have reasonable sewerage systems, although treatment plants for purification of waste waters are often inadequate. The situation in rural areas is considerably less satisfactory; although some of the more industrialized countries have already reached 95% coverage both in water supply and sanita- tion facilities, the position in some less developed parts of the Region gives rise to considerable concern. It is hoped that the rapid assessment, which will cover both quantitative and qualitative aspects, will provide an adequate basis for a coordinated action plan in which all Member States will be asked to participate with a view to achieving virtually complete population coverage by 1990. 13 2. WATER SUPPLY AND WASTES REMOVAL IN RAPIDLY DEVELOPING AREAS G. Watters 1 Provision of an adequate and safe water supply is a prerequisite for development, whether urban, industrial. or agricultural. Usually, all type s of development proceed in parallel as a district, region, or country advanc e s towards higher living standards and the importance of the water supply in- creases in direct relatic,nship to the demand for water and the rate at which development is planned to take place. The faster the development being aimed at, the more urgent the search for adequate sources of water . There is often competition between various interests for limited water resources, or for those that can be exploited economically using viable technology. Often, the various uses of a source are not comparable and priorities have to be established, or at least agreement reached on allocation of costs in relation to essential constructions such as dams and trunk supply mains. In regions entering the initial stages of rapid development, traditional utilization of sources and age-old legal rights can also form barriers to the optimum harnessing of a source. An example of a typical situation is that of a farming community traditionally using water from a natural spring for irrigation purposes during the growing season. With the coming of de- velopment and urbanization it sometimes happens that a source of clean water needing only minimal treatment (chlorina tion), as a health s a f eguard is being used for irrigation while the community is utilizing water from an in- ferior source and has to invest in expensive treatment plant. In most cases of this kind, the uses could be reversed and water from the inferior source used for irrigation, necessitating only construction of a pumping station and a delivery main for the community supply. This type of difficulty il- lustrates obstacles that may arise in th e "ideal optimization" approach to a regional water supply during the initial stages of rapid development. In assessing the economics of exploitin g a source and processing the raw water to produce a usable product, there is one overriding argument that goes beyond all financial considerations; the need to ensure a safe and hygienic domestic water supply for the population. Health considerations override all others and must be given top priority. 1 Project Manager, WHO Project for Community Water Supply, Waste Dis- posal and Pollution Control, Kosovo, Yugoslavia (project YUG/PIP 001). 14 DOMESTIC WATER REQUIREMENTS The difficulties of providing an adequate and safe water supply for a population are increased by the greater demands for more water as living standards improve and as modern labour-saving devices are installed in homes. This is reflected by the rise in the per caput water requirement experienced as the size of a community increases and more amenities are provided. At one end of the scale there is the remote rural community not connected to a central water supply, while at the other end is the residential area of a large town having a central piped water supply and facilities in all the houses. The difference in specific (individual) water consumption be- tween the two situations is very great; the rural dweller can satisfy his daily requirements with as little as 15 litres, whereas the urban householder requires as much as 400 litres. However, a major contributing factor in increased water consumption is convenience; if a villager has to carry water 100 metres to his house after drawing it from a well he will certainly use less than if he has a tap connexion inside his house. In a rapidly developing area a range of water supplies, from the most primitive draw-wells to the most up-to-date installations, can exist side by side. Improvement in convenience of supply is a major factor in changing the whole character of domestic water utilization during periods of rapid development, and this is particularly marked when the development starts from a very low level. Typical values for specific water consumption are given in Table 1, demonstrating differences in consumption in towns of different sizes at the present time and projecting future per caput water requirements for communi- ties of the same size (see also Fig. 1). Increased demand with time assumes continued economic and social development, and although the projected values are speculative they are based on past experience. The table shows clearly the effects of development on water consumption if it is accepted that living standards and levels of amenity increase with size of community and also with time. The first premise is borne out by documented information and the lat- ter is supported by history. One influence that increase in specific water consumption does have. and which helps to ease the difficulties of providing the supply, is that the ratio between the maximum daily required flow in the system and the av- erage daily flow becomes closer to unity. The result of this is to reduce the size of such elements as reservoirs, pumping stations, and pipelines, and hence to reduce the capital investment per person supplied. However . the problem of locating an adequate source of raw water remains, and increases as the town becomes larger. Typical values for the ratio of maximum daily water demand to average daily demand in litres per second (coefficient of unevenness) are presented in Table 2. This table, like Table 1, gives typical 1975 values and also presents projected values used for design and planning purposes up to the end of the century. 15 Table 1 TYPICAL WATER CONSUMPTION DATA, WITH PROJECTIONS UP TO THE YEAR 2000, FOR WATER SUPPLY DESIGN AND PLANNING PURPOSES Specific water demand Community size (litres per person/day) (no. of inhabitants) 1975 1980 1990 < 999 60 80 120 1 000 - 9 999 100 120 170 10 000 - 19 999 135 155 200 20 000 - 49 999 160 180 230 so 000 - 99 999 180 200 250 > 100 000 200 220 270 Table 2 TYPICAL VALUES FOR COEFFICIENT OF UNEVENNE&S OF WATER DEMAND1 Coefficient of unevenness of water Community size demand (kd) (no. of inhabitants) 1975 1980 1990 < 999 2.2 2.0 1. 9 1 000 - 9 999 1. 7 1.6 1.5 10 000 - 19 999 1.6 1. 6 1.5 20 000 - 49 999 1. 6 1. 6 1.5 so 000 - 99 999 1.5 1.5 1.4 > 100 000 1.5 1.5 1.4 2000 160 220 250 280 300 320 2000 1.8 1.5 1.5 1.4 1.4 1.4 1 Max. Qd/av. Qd = Kd, where max. Qd = maximum daily demand, and av. Qd = average daily demand. 16 !!Ll. TYPICAL INCREASE IN POPULATION AND WATER REQUIREMENTS FOR THE RESIDENTS OF A TOWN PROGRESSING FROM AN UNDERDEVELOPED RURAL TO A SEMI-URBAN NATURE1 19 3800 18 3600 I 17 3400 I 16 I 3200 15 B:. 3000 14 2800 13 2600 12 2400 11 2200 >, "' "" 0 I "C ..... -- >< 10 2000 ""s I ~ i:: "C 0 ..... I i:: ..., 9 & 1800 "' "' <J" s<l) ..... 0~ / \ "C :l a. ~ I-0 8 o◊ 1600 <l) p.. ..., "''"' 0 "' -:-,,'I> I 3 v 7 q,,o<I. <:ob /· 1400 ,;,'1' b"' • 6 <,, I 1200 "'"' . . f' I b • s .,_,., / 1000 .,v . 0--; / 4 ,q,,'- 0 800 / / 3 / 600 / 0· 2 / 400 B:. / / 1 / 200 .,,,,,. 0 - · - · 1970 72 74 76 78 80 82 84 86 88 90 92 94 96 98 2000 1 No allowance is made for industrial water requirements. 17 In Table 1, examples are given of the anticipated rise in specific water demand with time and increase in community size, both of which combine to produce an increase in living standards. To demonstrate the effect of this on the total water requirement of communities and the need for adequate plan- ning well in advance, the values in Table 1 have been used to project the water requirements of seven communities in the Socialist Autonomous Province of Kosovo, Yugoslavia. This area is currently undergoing rapid transition from a basically rural economy to that of a widely-based industrial society; in this process of change the United Nations Development Programme (UNDP) and WHO are assisting the authorities in developing water supply and waste disposal plans. Populations of the villages selected range from approximately 700 to 4000, with plans for development to around 5000-20 000 in the year 2000. It is considered that the greatest advances will take place within this growth phase and that the character of these communities will change dramatically from that of rural villages to one of urban towns. Community development of the seven villages. is summarized in Table 3. The results given in Table 3 are plotted in Fig. 2; data for Dragas are plotted separately since this town is beginning its development from a much lower level (population around 700) than the others, and its relative rate of progress will be much faster. Fig, 2 shows that the net effect of this rapid development is to produce a more rapid rate of increase in water demand in Dragas than in the other towns, where the growth rat es are approxi- mately equal. The table indicates the disproportionate relationship between population increase and the corresponding increase in domestic water requirements over the period up to the year 2000, i,e., on average, the increase in water re- quirements over the period is approximately 2-1/2 times greater than the in- crease in population, on the basis of the specific water demands adopted. However, this does not represent the total increase in the community ' ·s water requirements because industry is excluded in these calculations. The reason for this is that, because of the great variations in industrial requirements, their inclusion would completely distort the picture, AGRICULTURAL AND DOMESTIC SUPPLY Competition for available water resources and for funds to develop them. which are usually limited, is a feature of water supply development in a rap- idly advancing social and economic situation. Here, it is not always health and welfare criteria that are used in the establishment of priorities, Water requirements for agricultural production and the introduction of more valuable crops are normally many times greater than the domestic needs of communities, and hence justification for the construction of large reservoirs , etc., based on total requirements, rests on the needs of agriculture. Agricultural water demands of the order of tens of cubic metres per second predominate over urban requirements, a few hundred litres per second within the same service area. 18 PLANNED RAPID DEVELOPMENT OF SEVEN RURAL COMMUNITIES IN YUGOSLAVIA: INCREASED WATER REQUIREMENTS AND THE RELATIONSHIPS BETWEEN POPULATION INCREASE AND INCREASED WATER DEMAND Community 1971 1980 1985 1990 Dragas population 694 1 850 2 500 3 350 domestic water demand (m3 /day) 42 222 363 570 ratio of population increase 1 2 . 67 3.60 4.83 ratio of water demand increase 1 5.29 8 . 64 13. 57 Leposavi c population 1 187 3 600 5 000 6 350 domestic water demand (m3/day) 119 432 725 1 080 ratio of population increase 1 3.09 4 . 21 5 . 35 ratio of water demand increase 1 3 .63 6.09 9.08 Glogovac population 1 430 4 500 6 000 9 000 domestic water demand (m3/d ay ) 143 540 870 1 530 r atio of population increase 1 3 . 15 4.20 6.29 ratio of water demand increase 1 3.78 6 . 08 10. 70 Srbica population 1 654 3 500 5 500 8 700 domestic water demand (m3 /day) 165 420 798 1 479 ratio of population increase 1 2.12 3.33 5.26 ratio of water demand increase 1 2.55 4 . 84 8.96 Klina population 1 929 4 500 6 000 10 700 domestic water demand (m3/day) 193 540 870 2 148 ratio of population increase 1 2.33 3 .11 5.55 ratio of water demand increase 1 2.80 4.51 11.13 Vitina population 2 630 4 100 5 000 6 700 domestic water demand (m3/d ay ) 263 492 725 1 139 ratio of population increase 1 1.56 1. 90 2.55 ratio of water demand increase 1 1. 87 2.76 4 . 33 Suva Reka population 4 151 9 500 12 000 14 500 domestic water demand (m3/day) 415 1 140 1 740 2 900 ratio of population increase 1 2.29 2 . 89 3 . 49 ratio of water demand increase 1 2.75 4 . 19 6 .99 2000 5 000 1 100 7.20 26.19 9 000 1 980 7.58 16. 64 15 000 3 750 10.49 26.22 12 000 3 000 7 . 26 18 .18 20 000 5 000 10. 37 25. 91 10 000 2 500 3.80 9.51 20 000 5 600 4.82 13 .49 Notes : (1) ratio of population increase (Rd) = population in specified year /population in 1971; (2) r atio of water demand increase (Rd) = water demand in specified year/water demand in 1971; (3) values for water demand are for domestic purposes only and do not include industrial needs. 19 ~ 26 25 24 23 22 21 20 19 " 18 "' " 17 C ~ ~ " 16 w ~ "' 15 , ~ "' 14 !; !' w 13 ~ " C 1l 12 ~ " w 11 ~ "' , " 10 ~ u ~ -~ 9 e .. 8 6 5 0 RATIO OF COEFFICIENT OF WATER DEMAND (Rd) INCREASE TO COEFFICIENT OF POPULATION (~) INCREASE! I I I 0 I I I I I I I ' i I I I I I I I I I I Projec te d popul a ti on/ori ginal po pulation 10 11 R p 1 Communities in Sap Kosovo , Yugoslavia. wi t h populations of 1000 - 20 000 and a 5- t o 10-fold rate of growth o ve r a 30-yea r pe riod; values from Table 1. 20 This is normally the case in a developing area where a griculture is still the major element in the economic sector and urban development is in its initial phases. The result of this imbalance is that water resource development is usually oriented towards agricultural requirements without due regard to potable water needs. In some areas there may even be re- luctance to incorporate into any scheme special installations for domestic water supply, which are generally more expensive than similar elements for irrigation purposes, i.e., draw-off towers, covered conduits, etc., the gen- eral philosophy being that the irrigation system should be built and then the potable supply taken from from it by the best means possible. As an example of this approach reservoirs have been built with only one draw-off located near the bottom of the reservoir to obtain a maximum head of water for either irrigation of hydroelectricity generating purposes, the domestic system being expected to use the same draw-off. Such an approach does not allow for construction of a special draw-off tower for potable water to control the quality of the raw water, and hence reduce treatment costs, and to ensure the efficiency of treatment. If such special draw-off facili- ties are not provided, not only will unacceptable variations in water quality result, but conditions may occur that could render the source completely un- suitable for urban water supply - a build-up of high concentrations of man- ganese at the bottoms of reservoirs, for example. Another serious disadvantage of assuming that a potable supply can be provided as a minor part of an irrigation system arises from the pumping of water for treatment from irrigation water distribution networks. Most ir- rigation canals are open channels and are very susceptible to contamination since they pass through areas of intensive agriculture and human activity. As well as the normal wash-off, contaminants such as fertilizers, pesticides, and possibly even animal carcasses may flow into the channels. However, such difficulties can be controlled by introducing adequate safeguards and excercising proper control and regularly inspecting the system. The main difficulty that cannot be eleminated through good practice results from the inappropriate character of most irrigation systems to meet the demands of a domestic water supply and from the disproportion between the volumes of water required for agriculture and domestic purposes in most developing areas. This difficulty is perhaps best demonstrated by considering conditions prevailing during the winter or the nongrowing season, when no irrigation is necessary. Assuming a trapezoidal irrigation channel with 45° slide slopes, a bottom width of 1 m, and a depth of flow of 1.5 m, if such a channel is to supply a maximum requirement of 400 litres for domestic supply, the flow vel- ocity will be approximately 0.1 m per second. If the irrigation canal is 15 km long, the water will theoretically take about 2 days to reach the treat- ment plant after leaving the reservoir. By the time water reaches the ex- traction point, it will have deteriorated considerably and in some cases could show many of the characteristics of stagnant water with a dissolved oxygen level approaching zero. 21 The need for cleaning and dredging of irrigation canals also must be taken into account when assessing their suitability as a source of raw water for domestic supply since such activities will cause disruption of supply and prolonged turbidity of the raw water. These examples of difficulties that can arise from considering the pro- vision of potable water supply as secondary element in satisfying overall water needs for rapid development stress the importance of giving sufficient priority to the potable water supply requirements in advance of rapid de- velopment and implementing the solutions in parallel, and in harmony with the other needs. This is particularly important in relation to the opti- mization of source utilization. An inventory of all available sources in a region is a .most useful tool at the start of development. In this way the higher quality springs, etc., can be earmarked for potable supply at least cost while the sources of secondary quality, which are usually most abundant, can be used for industry and agriculture, where in most cases the total requirement is larger. INDUSTRIAL WATER DEMAND For development planning purposes each industry must be considered se- parately, and the industrial water requirements of each town must be treated on its own. Some industrial supplies, such as those for the food-processing industry, must be of potable quality and must therefore come from a town supply; however, other industries do not require water of drinking quality and therefore only need sources of secondary grade. The requirements of industry for secondary quality water are usually much greater than those for water of potable quality, so the need of each industry must be considered carefully during development planning. In this way, inessential utilization of potable water can be avoided, thereby not only saving money but also safeguarding valuable water resources. Within the framework of these planning considerations the location of industry in relation to sources is important. A full investigation should be made of possibilities for utilizing recirculation and other ways of sav- ing water within the plant. Although sufficient water may currently be available, water-saving procedures should be encouraged in order to prevent spoilage of resources and creation of resistance to savings at a later date. DISPOSAL OF LIQUID WASTES As rapid development creates problems for the authorities in their efforts to ensure that necessary water is available for urban and industrial needs, other difficulties arise in relation to the disposal of liquid wastes. If these are not tackled at the same time as water requirements are satisfied by the development of new sources, there may be disastrous consequences af- fecting potential sources of water supply. The detrimental effects of lack of foresight in planning liquid waste collection and treatment first manifest themselves to the public through the pollution of surface water, and the 22 seriousness of the situation is often not appreciated until attempts are made to tap the source for water supply purposes. In isolated farmhouses or small rural communities, prior to development and connexion to a piped water supply, the water consumption is, as already stated, very low, and values of the order of 20 litres per caput per day are normal. Under such conditions, not only is little liquid waste generated by the households, but it is purely domestic in nature and is allowed to seep into the ground either through latrine pits or the soil surface in the close vicinity of the house. Under such conditions, little, if any, waste ever reaches the water courses, and the small level of pollution to ground-water strata can be counteracted in most cases by disinfection of the water at the time of extraction for local supply purposes. The introduction of a piped water supply, however, changes this situation radically, and disastrous consequences may follow if the inherent dangers are not fully appreciated. As stated earlier, the first effect of intro- ducing a central water supply system into a community or region is a dramatic increase in specific water consumption. In the first instance this increase takes place mainly because of the convenience of the supply. With a 5-fold increase in water consumption within a short period, wastes can no longer be allowed to seep into the ground in the vicinity of dwellings and problems of collecting the wastes arise. If wastes are not collected through a sew- erage system conditions rapidly deteriorate, the situation becomes aestheti- cally unacceptable and, above all, a serious health hazard is created. Hence the construction of sewerage networks should proceed parallel with the introduction of a piped water supply. Unfortunately, all too often under conditions of rapid development, where there are many calls on the limited financial resources, the sewerage network is built but the construc- tion of a treatment plant for liquid wastes is regarded as a refinement that can be omitted, or at least postponed until a later date. The result is that the waste water problem is removed from the community generating it but the neighbouring water courses and downstream settlements suffer from the consequences. If a hypothetical town of 6000 inhabitants, for example, discharges its wastes untreated to a water course approximately 390 kg of biologically de- gradable material measured in terms of the 5-day biological oxygen demand (BOD5) is released to the river. This is sufficient material to convert a water flow of 150 litres per second into the equivalent of raw sewage, as- suming a BOD5 concentration in sewage of 300 mg/litre; this is a sizable stream. The only solution to this problem is early recognition that the construction of a waste treatment plant must be planned at the same time as the sewerage network and the two facilities gradually brought into com- mission together as the number of households connected to the sewerage sys- tem increases . From surveys of some typical rural and semirural communities in a rapidly developing area, the cost of providing full biological treatment to an ef- ficiency of 90% in respect of BOD5 removal is found to range from 20% to 60% 23 of the cost of the associated drainage and sewerage networks. This wide range results from differences in topography and local conditions and on whether a combined sewerage/drainage system or separate systems are adopted. In view of the high cost, authorities are naturally reluctant to make any commitment to such an investment unless the expected benefits are fully understood. However, it is particularly important to plan all aspects of water utilization together in areas where rapid development in the form of urbanization and industrialization is anticipated, particularly if develop- ment will change the character of communities from a predominantly rural to an urban nature. The collection and disposal of liquid wastes cannot be treated under such circumstances independently and as an activity to be post- poned for a later date; it must form part of the overall water resource ex- ploitation planning. PERSONNEL REQUIREMENTS An important element of environmental planning to satisfy the demands of development is forecasting needs for suitably trained personnel and the taking of steps to ensure that they are available when required. Theim- portance of manpower development cannot be emphasized; too often in the past care of local waste treatment plants or refuse disposal dumps has been left in the hands of untrained personnel because of the low social status of the work. This attitude is particularly prevalent in developing areas, where no experience or tradition exists of organized waste disposal. It is therefore important that manpower planning and training should be conducted to keep pace with rapid development and that facilities and personnel should be available for water supply and waste removal and treat- ment, enabling development to take place without risk to valuable water re- sources needed for the implementation of future development plans. CONCLUSIONS The provision of an adequate supply of good water is essential for rapid development, whether urban, agricultural, or industrial . However, it is not only necessary to provide sufficient water but also to plan for future needs, to make an inventory of resources, and to optimize the utilization of water sources. These actions are necessary to guarantee that future re- quirements will be provided for and the rationalization of investments in water supply development ensured. Action necessary to ensure the transport, treatment, and disposal of liquid waste must be treated as an essential element of a water supply system and not postponed until a later stage of development. Only if this approach is adopted can utilization of limited water resources be planned and opti- mized in such a way as to assure unimpeded development. Water must be seen as a natural resource with a limited potential for exploitation and treated 24 with care and respect. In this way, the necessary supplies for rapid de- velopment can be made available and play their essential part in maintaining acceptable environmental standards and community health. An important element in planning the development of water resources and ensuring successful implementation of proposals is provision of the sui- tably trained personnel to design and operate the systems. This can only be achieved through manpower development planning and an understanding of the high level of training necessary for such work. As living standards improve, water requirements for domestic purposes grow at a faster rate than population increase and under conditions of rapid economic growth the water demands of industry and agriculture also rise steeply . It is clear that foresight and comprehensive planning are vital for meeting future water needs. 25 3. HOUSING HYGIENE IN EUROPE ----E. Giroult1 At the end of the 19th century European scholars showed that the prevalence of tuberculosis, one of the major causes of mortality at that time, was partially connected with environmental factors, particularly with unhealthy accommodation and inadequate heating in dwellings. As a result, health regulations in respect of housing were drawn up in numerous countries, dealing, in particular, with temperature, dampness, amount of sunlight, ventilation, thermal and sound insulation, living space, and minimum sizes of entrances to dwellings. Architects and builders were forced to alter their concepts in order to comply with the regulations. Since then it has become evident that other correlations exist between infectious or degenerative illnesses and some of the environmental factors linked with human settlements or poor town planning. More precisely, mental health is affected by overcrowding, inadequate sound insulation, and sociological imbalance caused by large-scale modern dwelling zones. Such a situation gives added point to the problems of housing hygiene. Along- side the continuing existence of areas with insanitary dwellings in the traditional sense of the term a new problem has appeared in many areas of Europe: psychosocial disturbances stemming from low-cost modern housing, apparently adequate from the standpoint of physical hygiene standards but inadequate from the aesthetic, sociological, and psychological points of view. The WHO Regional Office for Europe has long been associated with the study of public health problems associated with housing conditions, and this programme is still being developed, having been given new stimulus by the recent United Nations Conference on Human Settlements ("Habitat") in Vancouver, Canada. DISEASES ASSOCIATED WITH HOUSING A WHO Expert Committee meeting in Geneva in September/October 1972 to study the uses of epidemiology in housing programmes and in planning human settlements made a distinction between two situations: (1) legally unhygienic housing failing to comply with regulations in force relating to the hygiene of dwellings, and (2) housing complying with current regula- tions but not entirely satisfactory, if only at the level of mental health. 1 Regional Officer for Basic Environmental Services, WHO Regional Office for Europe. 26 Insanitary housing of the traditional pattern Tuberculosis is more frequent among persons living in damp, poorly heated or poorly ventilated dwellings or those admitting insufficient sun- light. Other respiratory conditions are associated with these same factors. Rickets in children and stunted growth are more frequent among those who live in dwellings where there is little sunlight. Eyesight disturbances appear among those living in poorly lit housing. Waterborne diseases, digestive disturbances, intestinal parasites, and vermin-transmitted dis- eases are all connnon among those living in dwellings that are not equipped, or are poorly equipped, with toilets, bathrooms, kitchens, running water, and sanitation. Domestic accidents are more frequent in dwellings that are overcrowded, poorly designed, or badly fitted. Mental disturbances, among both children and adults, are associated with overcrowding in cramped dwellings or in congested buildings and districts. Inadequate modern housing Those inhabiting such dwellings may suffer two types of damage to health: on the one hand, accidents of all types, such as those resulting from defec- tive timberwork, plumbing, heating, or electrical systems, and cases of poisoning resulting from the use of certain building materials, paints or finishes; on the other hand, mental disturbances caused by excessive noise, inadequate living space, and, above all, a lack of human balance in the large-scale, low-cost edifices erected in many urban developments. Mental disturbances of this type have a particular impact on population groups of rural origin who have recently moved into an urban environment. THE NEW SCALE OF THE HOUSING PROBLEM IN DEVELOPING COUNTRIES At the United Nations Conference on Human Settlements the disastrous effects of the population explosion on the chief cities of developing coun- tries was described. This phenomenon is of direct concern to the European Region of the World Health Organization, which includes three developing countries, Algeria, Morocco, and Turkey; all three are suffering from over- rapid population growth . For example, the city area of Istanbul may have a population of 14 million by the year 2000, while Algiers is expected to have at least 5 million inhabitants by the same date. Moreover, population increases will result in an expansion of urban areas at the expense of fer- tile farming land and radical alteration of geographical features, causing sharp deterioration in the environment and a potential threat to health. The WHO Regional Office for Europe is ready to make a contribution to- wards solving problems of public health and environmental sanitation, and in providing the technical assistance needed by countries affected to cope with the consequences of the explosive growth of cities. WHO is also mak- ing great efforts towards development of more effective family planning, still the only long-term solution to explosive population growth. 27 THE ROLE OF THE HEALTH ENGINEER IN HOUSING HYGIENE This consists in making use of the conclusions and recommendations of experts in medical hygiene and in developing standards and criteria to be used by architects and builders. The physiological foundations for housing hygiene have been clearly demonstrated, and epidemiologists can establish correlations between physical factors in housing associated with morbidity. Psychiatrists must try to do the same in relation to mental illness and social problems. The architect and builder both require quantitative criteria and regu- lations on which to base their designs. This applies equally to individual dwellings and entire housing developments. One of the basic quantitative standards should be the minimum amount of living space in terms of area or volume to be allocated to each individual occupying a dwelling. The town planner requires standards for producing overall designs for housing developments and also guidelines and quantitative reference data relating to the selection of population densities for housing, etc. THE ROLES OF ECONOMIC AND CULTURAL FACTORS Housing hygiene regulations and standards established for reasons of health must be differentiated from those motivated by a desire for comfort . In fact, we should not forget that economic constraints on the cheapest types of dwelling are given all the more consideration because those responsible for their design are not those who live there. Moreover, where there is severe shortage of housing dwellings become overpopulated. As regards town planning also, factors touching on the health or com- fort of the population must be differentiated from those connected with sociocultural habits or the architect's imagination. For example, does the choice between apartment buildings and individual houses depend on national tradition, economic considerations, or is there real proof that the health of children raised in individual houses is better than that of those growing up in apartment blocks? Similarly, are high-rise buildings due to the out- come of financial necessity or simply products of the architect's imagina- tion? Are there serious reasons for believing that the mental balance of people living in high-rise accommodation may be affected or that the risk of domestic accidents is particularly high? PROPOSALS FOR INTER-EUROPEAN ACTION Exchanges of information by European countries on housing hygiene would be useful and comparisons of standards and regulations relating to hygiene in human settlements, town planning, and building techniques would help coun- tries to up-date their legislation. The circulation of summary results of relevant epidemiological, psychological, hygiene, and medical studies would permit clarification of certain questions or show the need for further studies. 28 Decision-making in housing and town planning would be made easier for governments by drawing a clear distinction between factors proper to public health on the one hand and economic and cultural factors on the other. REGIONAL PLANNING Health standards for dwellings lead on to health standards in town planning, i.e., public health considerations in concepts in urban develop- ment, whether they concern the establishment of health care facilities or the control of industrial pollution. Town planning activities can be extended to cover the definition of human settlement policies based on public health considerations. For ex- ample, it would be interesting to know whether, in certain European countries, there is proof that the health of rural populations is better, or worse, than that of urban communities. Similar comparisons could be made between those living in small towns and in major and capital cities. CONCLUSIONS The above-mentioned problems are much more important for cities in European countries than for cities in developing countries still facing the major task of eradicating shanty-town areas. It is therefore important to treat them within a European context, while possibly including also other countries, such as Japan, that have reached a comparable stage of develop- ment, suffer from high population density and have only limited natural re- sources for tackling the problem of poor housing hygiene. SELECTED READING Andrzejewski, A. et al. Housing programmes: the role of public health agencies . Geneva, World Health Organization, 1964 (Public Health Papers, No. 25) Goromosov, M.S. The physiological basis of health standards for dwellings. Geneva, World Health Organization, 1968 (Public Health Papers, No. 33) Lanoix, M. The engineer, the architect and the town planner in their re- lationship to health engineering. Geneva, 1972 WHO Technical Report Series, No. 225, 1961 (Public health aspects of housing: first report of the Expert Committee) WHO Technical Report Series, No. 250, 1963 (Urban health services: fif th report of the Expert Committee on Public Health Administration) 29 WHO Technical Report Series, No. 297, 1965 (Environmental health aspects of metropolitan planning and development: report of a WHO Expert Committee ) WHO Technical Report Series, No. 353, 1967 (Appraisal of the hygienic quality of housing and its environment: report of a WHO Expert Committee) WHO Technical Report Series, No. 511, 1972 (Development of environmental health criteria for urban planning: report of a WHO Scientific Group) WHO Technical Report Series, No. 544, 1974 (Uses of epidemiology in housing programmes and in planning human settlements: Report of a WHO Expert com- mittee) World Health Organization. Human settlements and health. Report prepared for Habitat: World Conference-Exposition on Human Settlements, Vancouver, 1976 (document A/Conf. 70/15) 30 4. DESIGN AND IMPLEMENTATION OF COMPREHENSIVE ENVIRONMENTAL POLLUTION CONTROL PROJECTS with special reference to the UNDP/WHO-assisted environmental pollution control project in the Athens metropolitan area P . H.A. Gilad1 This article describes the design and implementation of a typical com- prehensive pollution control project executed by the World Health Organiza- tion Regional Office for Europe . POLLUTION CONTROL Identification and definition of the components of an environmental pollution control programme serve to clarify subsequent discussion of plan- ning methodology. Fig. 1 shows the relationships between various factors and activities involved in the generation and control of pollution. All human activity, whether production or consumption, gives rise to residuals, some of which can be readily reused or recycled back into the production process (Fig . 1, arrows 1-3). Residuals that cannot readily be reused or recycled become wastes; these may be discharged into the environment, either in their original form or after treatment (Fig. 1, arrows 7-9). The environment possesses a certain capacity to assimilate without ill effect some of the wastes discharged into it (Fig. 1, arrow 10). Those wastes that cannot be assimilated harmlessly into the environment result in pollution (Fig . 1, arrow 11). Environmental pollution has certain detrimental effects; some of these are known, others are suspected. Both the known and the sus- pected effects of pollution evoke public concern (Fig. 1, arrows 12 and 13). When public concern becomes strong enough, it usually results in environ- mental legislation (Fig. 1, arrow 14) or pressure for the more rigorous enforcement of existing legislation (Fig. 1, arrow 14a). This legislation is enforced to a greater or lesser extent (Fig. 1, arrow 15) and influences the various elements of the pollution-generating process. Some legisla- tion is aimed at facilitating or encouraging recycling of residuals before they become wastes; this may be achieved by differential taxation or introduction of charges, subsidies, or other inducements to recycling. 1 Project Manager, Environmental Pollution Control project, Metropoli- tan Area, Athens (project GRE/CEP 001) 31 MODEL FOR POLLUTION CONTROL 103 ,-- Cost of .... - - - -- - - - - - ------• Cost/benefi t pollution control - __ .. analysis -- ---! 25 - -- I 26 - -- - 105 I -- - - I 104 - -- I Economic activity : -- -production and ~ -- I consumption 27 Interest and I pressure groups I I 1 3 I 29 28 I I 24 ~ I Recycling I I 2 I I • Enforcement 15 Residuals or - Legislation inducement 4 5 6 23 Product+ process 17 modification - 14a 14 102 Wastes Public concern (pressure groups) 7 is 22 ~ Treatment 19 21 Dispersion 19 - or deposition 11 110 Assimilation 20 ~ 13 Suspected and I- _1~:.. Cost of Pollution known effects pollution of pollution 32 It is frequently possible to modify production processes, or even pro- ducts, to reduce the amount of wastes generated or to change their composi- tion so that they can be more easily recycled into the production process (Fig. 1, arrows 16 and 17). Other types of environmental legislation may prescribe mandatory treatment or provide inducements for treatment, either through imposition of selective users' charges or granting of subsidies (Fig. 1, arrow 18). It must be borne in mind, however, that treatment does not reduce amounts of wastes but only changes their composition or physical state to facilitate their dispersion or assimilation. Some types of envi- ronmental legislation attempt to influence the dispersion process by requir- ing high stacks for dispersion of gaseous emissions, or outfalls and dif- fusers for dispersion of liquid wastes (Fig. 1, arrow 19) . Other types of environmental legislation attempt to regulate the per- mitted degree of pollution, leaving polluters or enforcement agencies free to choose the methods by which the prescribed environmental standards are to be achieved (Fig. 1, arrow 20). Nearly all pollution abatement methods require financial outlay. The accumulated cost of all measures aimed at reduction of pollution (Fig. 1, arrows 21-24) represents the total cost of pollution control. These costs, when charged either directly or indirectly to the products, are bound to affect the composition and mix of the economic activity (Fig. 1, arrow 25). This, in turn, results in public interest or concern and pressure groups may be formed with the purpose of minimizing pollution control costs and their possible detrimental influence on economic activity (Fig. 1, arrow 26). Such groups exert pressure on both legislative bodies and enforcement agen- cies to withhold or modify legislation or to restrict enforcement. It is worth noting that the system is kept in equilibrium by conflicting public pressures, on the one hand, and those of special interest groups, on the other; the political process is therefore essential for resolving conflicts and maintaining an equilibrium. The present and future effects of environmental pollution are not pre- cisely known and therefore the cost of pollution is very difficult to esti- mate. It is also extremely difficult to forecast with any degree of accuracy the effects of pollution control costs on the economy. For these reasons, it is difficult to perform valid and dependable cost/benefit ana- lyses and arrive at rational decisions (Fig. 1, broken arrows 101-105). DESIGN OF THE ATHENS ENVIRONMENTAL POLLUTION CONTROL PROJECT The Athens project has been designed to deal to a greater or lesser extent with each of the components shown in Fig. 1. The project is a co- operative venture of the Government of Greece, the United Nations Develop- ment Programme (UNDP), and the World Health Organization acting as Executing Agency on behalf of UNDP. The major objectives of the project are to assist in the development of an adequate environmental data base and control programmes for air, water, solid wastes, and noise, and to facilitate 33 development of environmental strategies and policies, administrative struc- tures, and legislative and enforcement apparatus. In 1972, at the time the project plan was prepared, the major obstacles impeding progress in maintaining and improving the environmental quality of the area were as follows: (1) inadequate information; (2) insufficient professional and technical manpower; (3) dispersion of administrative responsibility; (4) lack of comprehensive planning. The project has been designed mainly to assist the Government of Greece in overcoming those problems. The Geographical Area The second important consideration in determining the scope of pollution control activity is the area to be covered by the project. Local projects covering very limited areas circwnscribed by administrative or political jurisdictional boundaries are not likely to produce optimal results. A solu- tion that may be advantageous for a city may prove disastrous for a metropoli- tan area of which the city forms a part because the effects of pollution are often experienced outside the area in which the pollution is generated . To minimize the effect of these externalities on the planning process the envi- ronmental pollution control plans should cover the entire area within which emissions discharged at any point produce significant environmental effects. The Athens metropolitan area contains major population centres, major industrial concentrations, a large harbour, and very important tourist and recreational facilities. All these pose significant and conflicting demands on the use of environmental resources . Explicit resolution of these con- flicts through a solution that would be politically, technically, and econo- mically feasible demands that the entire peninsula of Attica, including some of the neighbouring islands, be included in the study area. 1 Taking into consideration limitations on time and resources, it is im- possible to study all parts of the project area in the same degree of detail. It is intended, however, to study the entire area in sufficient depth to pro- vide consistency of approach and to avoid diseconomies which may be introduced by externalities. 1 The Athens metropolitan area, comprising the peninsula nearby islands, lies approximately in the centre of Greece. 56 municipalities and communes and has an area of 2400 km2 . population was 2 705 000. 34 of Attica and It consists of In 1975 the The Planning Horizon Another parameter of project scope is the planning horizon. Protect- ive and remedial measures that are effective and economical for the immediate future may become counter-productive i n the long run. On the other hand, our capacity to forecast the conditions and to develop appropriate plans diminishes rapidly as the planning horizon lengthens. Fig. 2 is a three- dimensional matrix showing the spectra of environmental sectors, geographical areas, and planning horizons that form the parameters of project scope. Ideally, environmental pollution control projects should develop long- term plans, cover very large geographica l areas and include all sectors of the environment. It is obvious, however, that such plans would require excessive investment of resources and time and would be extremely difficult to execute, from both the conceptual and practical points of view. Within the limits imposed by resources and time, the short-term impact of a project tends to vary inversely with its scope. One possible way of solving this difficulty is to institute a hierarchy of projects. Comprehensive , long-term projects that are country-wide, con- tinental, or even global in scope would aim at monitoring general trends and establishing broad guidelines and criteria. At the same time, regional or local projects would develop short-range and medium-range plans aimed at solving local environmental problems and controlling local sources, within the guidelines developed by the broad global projects. This approach is practised by the WHO Regional Office for Europe. The Long-Term Programme in Environmental Pollution Control involves cooperation of all countries in Europe and is concerned with monitoring, manpower train- ing, development of criteria and guidelines, establishment of codes of prac- tice, etc. On the other hand, the country programme aims at assisting in- dividual Member States in developing short-range and medium-range plans for environmental pollution control. Thus, a hierarchy of projects dealing basically with the same problem but varying in scope, depth, and detail is being established, and this multilevel approach assures effective and prompt action at the local level, providing at the same time, a broad framework for coordination and consistency of approach. In the Athens project, the conflict between efficiency of the long-term view and feasibility of the short-term solutions has been partially resolved through a dual approach to the problem. While master plans will be devel- oped for the entire study area, preliminary engineering and feasibility studies will cover only those components of the master plan that are sche- duled for construction and implementation within the next 5 years, thus covering the most important and pressing needs. In addition, an immediate action programme is being developed, aiming at the solution of problems that require no additional data and do not depend on considerable investment for their solution. 35 Fig. 2 CONTENT, RANGE, AND SCOPE OF ENVIRONMENTAL POLLUTION CONTROL PLANS ~ Long-range plans /~- --/ Medium-range plans Short-range plans Immediate measures C: ...... "' "' w w · rl C: ...... ...... <lJ :>, "' 0 ...... C: H C: p. "' •rl w 0 <lJ 0 ,-; ..0 w C: •rl w H "' 0 C: ;:l 00 "' w cJ ...... 0 0 <lJ w <lJ 0 t.? u u i:,:: U'.l l:: ....:l I· Spatial range 36 (/) e <lJ ...... ..0 0 H p. ...... "' w C: Cl; e C: 0 H •rl ;,- c: i>l y Project Components Fig. 3 shows the main components of a typical environmental pollution abatement activity. These can be classified under the headings of inform- ation, manpower, plans and progrannnes, technology, public support, and government commitment and action. Information The first and main requirement for any rational activity is information, which serves to identify the problem and to define its magnitude and impor- tance, and permits development and evaluation of policies and programmes for corrective actions. Although collection of environmental data is a major activity for environmentalists, much of this effort is uncoordinated and dis- jointed, and the potential usefulness of the results is thereby diminished. Data are often collected just because they can be collected or because instrumentation or budgets are available, without regard to the ultimate purpose of the information. Such procedures are not only wasteful in material and human resources but, more important, frequently result in un- necessary delays of corrective actions, since protracted monitoring may serve as an excuse to postpone decisions. WHO, recognizing the importance of this activity, organized a symposium on the design of environmental information systems, in Katowice, Poland, in January 1973. Papers presented at this symposium have been published in book form. 1 The following information is usually needed for pollution control programmes: (1) types and concentrations of pollutants in the environment; (2) temporal and spatial distribution of the pollutants; (3) sources, quantities, and composition of discharges; (4) the fate of pollutants in the environment, their decomposition, dispersion, absorption in food chains, etc.; (5) the effects of pollutants; (6) pollution forecasts and trends . 1 Deininger, R.A., ed. Design of environmental information systems. Ann Arbor, University of Michigan, School of Public Health 37 \.,.) co Fi_g_. 3 - ENVIRONMENTAL POLLUTION CONTROL ACTIVITY (PROJECT) COMPONENTS Information Plans and Technology progralllllles ~ Monitoring and evaluation of results ~ ~ Manpower . Government action Public support It is necessary to establish and operate monitoring networks and ana- lytical laboratories, and to collect and interpret large amounts of data'. To obtain information on present and future quantities and types of dis- charges it is often necessary to perform special surveys, make forecasts of population growth and industrial development, and obtain information on water consumption, industrial processes, etc. It is obvious that, unless the information system is carefully designed, the environmental information activity can take many years to complete and require an excessive share of resources. As shown in Fig. 4, the information system can be subdivided into three basic components - namely, data collection, data processing, and information delivery. Too often, at the onset of the progranune the entire effort is devoted to data collection, producing a mass of raw, unrelated, and undi- gested data, of limited usefulness. Early attention to the data-processing activity is necessary for sever- al reasons. First of all, it permits early evaluation of the data collec- tion system and makes it possible to introduce the changes and adjustments needed to produce a coherent set of data. Secondly, it leads to early and parallel development of statistical and analytical skills, without which i t is often impossible to make sense of the collected data. Thirdly, it per- mits early activation of the information delivery system. The third point merits special attention. The nature of the data collection activity is such that it is never completed and it is always possible, and frequently necessary, to improve the output continually by increasing the variety, accuracy, and reliability of the data. It is therefore advisable to weigh carefully the risks of publishing imperfect information against the risk of delaying decisions on preventive or corrective actions until better quality data are available. As indicated in Fig. 4, it is necessary to design the information de- livery subsystem, to avoid waste, prevent overloading, and ensure that the various information needs of the public and the agencies concerned are satis- fied to the fullest extent possible. Data collection, collation and interpretation, and information delivery together form one of the most important groups of activities of the Athens project. Limitations of space do not permit a full description but a sum- mary is given below to illustrate the scope of these activities. Water pollution control A large amount of data has been collected on the existing sewerage system in Athens and on t he quantity and composition of the liquid wastes generated in the metropolitan area. A study of the absorptive and dis- persive characteristics of the Saronikos Gulf has been conducted by the Greek Institute of Oceanography and Fishery Research in collaboration with foreign scientific institutions. 39 Research and training Status and trends ENVIRONMENTAL INFORMATION SYSTEM Purpose of information Problem definition Feedback system Preventive or corrective action Data collection subsystem Determination of parameters Location of sampling points Frequency of sampling Methods for sample collecting and handling samples Type, method, and precision of analysis Users of information Policy and programme alternatives De.sign of information system Data-processing subsystem Sensitivity of decisions to information Data collation Data aggregation Statistical analysis Data interpretation Lnventory of users Information delivery s ubsystem Definition of type and form by user ca tego ry Public information Ala rm sys tern Ad hoc reports Regular reports The task of compiling an industrial wastes inventory in the Athens metropolitan area commenced in May 1975. Initially, efforts were concen­ trated on the collection and classification of pertinent information from various government agencies. The inventory is now approaching completion and contains production and consumption figures for approximately 1000 in­ dustries expected to produce liquid wastes in the Athens area. Some data on the volume and characteristics of the liquid effluents have been collected for some 700 factories. The objective of this survey is to obtain a first estimate of the liquid wastes problem in the Athens metropolitan area. The accuracy of the estimations will be improved in successive steps as more in­ formation is compiled. Data already collected have been collated and interpreted and will serve as a basis for the design of the Athens sewage collection and disposal system, which is to be constructed under a Ministry of Public Works contract. Community noise abatement Sources and levels of been measured and analysed. the subjective responses of noise in several typical areas of Athens have A social survey has been conducted to measure citizens to community noise. A programme to measure noise emitted by motor vehicles has been insti­ tuted in cooperation with the traffic police. Based on the results of this work, proposals have been developed for establishing noise emission standards for certain categories of vehicles and machinery. Some action has already been taken to reduce the level of traffic noise, e.g., by restrictions upon the use of motorcycles within the city area. A preliminary survey of noise emanating from the airport has been con­ ducted and proposals for corrective action have been submitted to the Civil Aviation Authority. Solid wastes management Quantity and composition of solid wastes generated in Athens have been analysed and various alternative methods of disposal (land-fill, incinera­ tion, etc.) examined from the technical and economic points of view. The feasibility of composting and recovery of materials has been studied and pilot plants have been designed to test the technological processes involved and to study the market for the resulting products. Air pollution control An air pollution monitoring network has been established and put into operation, and data on sources, levels, and temporal and spatial distribu­ tion of the various air pollutants have been generated. Analysis of these data has permitted identification of the most important contributors to air pollution in Athens. An "immediate measures" programme has been formulated which, if acted upon, would significantly reduce the levels of air pollution in Athens at a very moderate cost. 41 An epidemiological study of the health effects of air pollution in Athens has been conducted. The effects of air pollution in Athens on various materials such as steel, nylon, rubber, etc., have been measured to serve as an input for a subsequent cost/benefit study. Atmospheric dispersion models have been tested, adapted and activated to permit assessment of the probable impact of the various air pollution control strategies to be developed during the next phase of the project . A rigorous reporting system has been instituted by the project, project teams and cooperating institutions being required to submit regular inter- pretati ve reports. These are later used in project semi-annual reports. Consultants' reports are processed quickly and are usually distributed to designated recipients a few weeks after the termination of the consultant's mission. In December 1975 the project produced a comprehensive Interim Technical Report comprising four volumes with a total of over 1500 pages. The report is based on the reporting system described above, without which it would not have been feasible. Manpower Meaningful programmes cannot be planned or executed without adequately trained manpower. Lack of scientists, engineers, and technicians familiar with environmental pollution problems and having a knowledge of control and abatement methods is often the greatest obstacle to successful action. Fig. 5 illustrates the vicious circle that frequently develops before envi- ronmental control activities begin, and constitutes a major obstacle to en- vironmental manpower development. Since no major environmental programmes are in operation, there are few career opportunities for environmental pro- fessionals and very little interest in, and few candidates for, training. The consequent lack of training facilities and programmes results in shortage of environmental manpower, without which viable environmental programmes cannot be conceived, planned, and put into operation. Planned intervention is needed to break this cycle and permit orderly development of environmen- tal manpower at all levels. To assist in this task, a consultant was recruited to assess present and future requirements for personnel in Athens. His report presents esti- mates of future needs for trained manpower to operate a comprehensive envi- ronmental pollution control programme in the Athens metropolitan area. Detailed staffing tables are provided for each sector, and methods are dis- cussed for selecting and applying input data reflecting the physical environ- ment of the area, drawing up personnel distribution lists, and recruiting staff for specified pollution control functions. The report provides a baseline estimate of the trained manpower that would have been needed had a fully comprehensive programme been in operation in the Athens area at this time. This baseline, in the form of an aggregated number of positions for 42 Fig. 5 Competent manpower MANPOWER SHORTAGE CYCLE Environmental programmes Training programmes 43 Career opportunities Training facilities and budgets Availability of trainees all required functions, is the main source from which manpower requirements for 1986 are determined. Post descriptions for selected occupations rele- vant to the environmental pollution control programme are also included in the report. The formal training programme for the project developed slowly in the beginning because of a conflict between training requirements, on the one hand, and the need for personnel to carry out essential work, on the other. However, with the expansion of the project staff, and especially with the return of the first groups of trainees from fellowship studies in other countries, the training programme gained momentum and is now fully operative. Four training methods have been used - namely, in-service training through collaboration with WHO consultants, training courses and seminars organized by the project, participation of project staff in courses given by Greek national institutions, and awards of fellowships for training in other countries. The last category can be subdivided into three types - namely, in-service training in established institutions, academic courses normally leading to advanced degrees, and attendance at international courses and seminars. Fig. 6 shows the various means of training employed and the primary and secondary training objectives of each. In retrospect, it seems that the mix of different means of training was successful since there was a highly satisfactory and rapid development of project professional staff. Development, Adaptation, and Utilization of Technology Every action aimed at reduction and control of pollution depends on facilities, equipment, and processes supported by expertise in their appli- cations, use, and maintenance. A broad range of technologies is involved, depending on the nature of the intervention applied in each case. Given the great variety of technological requirements of every pollution control project, and considering the unequal distribution of technological skills in different countries, the question often arises whether it is more econo- mical to develop the required technology locally or to import it from elsewhere. This question is seldom considered on purely logical grounds since fac- tors such as national and local pride, professional ambitions, and personal and group interests often play important roles. Too often, a great deal of time, resources, and manpower are devoted to the local development of technology that has already been developed and tested elsewhere. Since lack of technological expertise often accompanies scarcity of trained manpower and resources, it is wasteful to devote limited means to such activities when the outcome may be doubtful and the product obtainable readily elsewhere. 44 .,.. \J1 ~ TRAINING PROGRAMME, .OBJECTIVES AND MEANS1 In-service In-service Short training Academic Courses or International training through training at courses and courses academic seminars and Training collaboration with established seminars given abroad programmes courses objec'tives consultants institutions locally by available abroad foreign experts locally (1-6 weeks) (2-8 weeks) (1-14 days) (9-18 months) (3-18 months) (5-10 days) Ac quisition of a narrow range A of skills directly related 120 ) to current work '------" Familiarization with methodology, 8 A operation of specialized equipment , exposure to good professional practice Overview of theory and practice V ~ A related to current and future w6rk (perspective and context ) Keeping abreast of trends and V A 0 developments in the profession; establishing professional contacts Acquisition of basic related I~ or peripheral skills useful for current or future work Broad professional training ~ V for wider responsibilities 5 (present and/or future) 1 Encircled figures represent numbe r of train ee- exposures . benefits, represented by the cones. In practice, each training means is likely to produce a spectrum of secondary It is often argued that local research and development activities, regardless of the succes•s of their outcome, contribute significantly to the training and development of local expertise. This is undoubtedly true, but the question remains whether the training objective could not be achieved by more efficient means than as a by-product of unproductive research acti- vities. The mixture of foreign and local contributions in transfer and adapta- tion of technology varies over a wide spectrum. Import of technology can take many forms, ranging from purchase of complete installations under "turn-key" contracts to acquisition of rights for local manufacture and use of equipment developed abroad. Turn-key contracts, in spite of their obvious advantages of speed and efficiency, possess some very significant disadvantages in so far as they contribute almost nothing to the development of local technical capability, which is important for subsequent operation and maintenance of the instal- lations. An optimum combination of indigenous input and the imported technology should be aimed at in each case. The imported component should be the minimum necessary to ensure a satisfactory product. The local contribution should be the maximum consistent with existing constraints of time, trained personnel, and physical facilities, taking into consideration their alterna- tive uses. In the Athens project a carefully balanced mixture of indigenous effort and imported expertise is applied. The major study leading to the develop- ment of the master plan, preliminary engineering design, and feasibility study for a liquid wastes disposal system will be entrusted to an experienced foreign firm of consulting engineers. This decision has been made by the Government in view of the lack of local firms possessing adequate experience of projects of this magnitude and complexity. Special care has been taken, however, to ensure that under the terms of the contract with the foreign firm local capability will be developed to the fullest extent possible. Firstly, the foreign firm will enter into partnership with a local firm that will collaborate on the entire project. Secondly, the Government of Greece and local institutions such as the Institute for Oceanographic and Fisheries Research will be responsible for supplying the bulk of the oceano- graphic data input needed for the project. The water pollution team working directly in the project office has generated most of the available data on the quantity and composition of the Athens sewage. The project microbiological laboratory is in operation and will perform all necessary tests and analyses. The source inventory team of the project is collecting the data on industrial liquid wastes in Athens. By integrating the work of the foreign firm of consultants with efforts made by local institutions and professional personnel, it is hoped to utilize 46 forei gn expertise fully while devel oping l ocal cap abili ty t o deal with the subject after the depa rture of the f oreign advisers and contractors. GOVERNMENT AND PRI VATE COMMITMENT The components o f environmental pollution control projects mentioned earlier in this article can be regarded as preparatory steps for action. Information, manpower, plans, and programmes are meaningful only to the extent that they facilitate commitment of public and private resources and result in remedial actions taken by individuals, firms, and governments. In this context, government actions consist of legislation, budgetary allo- cations, taxation subsidies, etc. An important element of government action is the establishment and maintenance of an enforcement system, with- out which none of the other activities can be fully effective. Recent experience in many countries has shown that a central environ- mental administrative body is essential for effective functioning of the system. Various countries have established different forms of central environmental agency ranging from interdepartmental committees with coordi- native and consultative functions to full ministries with policy-setting, legislative, and executive powers. Recognizing the importance of a central administrative body for envi- ronmental pollution control, the Government of Greece requested the assist- ance of WHO in designing the future Greek Central Environmental Agency. Consultants recruited by WHO from among leading environmental administra- tors in Europe and North America have visited Greece, examined the situa- tion, discussed the problem with the government officials at all levels, and submitted recommendations. Legislation has been passed establishing a system of environmental administration in Gree ce and assigning the var- ious functions of environmental control to the government departments con- cerned with provision for centralized coordination. In parallel with the se activities the "irrnnediate action progra=e" described above has been developed and several of the most important recom- mendations have been put into effect by the Government, thus leading to early improvement of environmental quality in the project area. Since the cost of pollution generally falls externally to the polluter, various types of taxes and charges are imposed with the aim of internalizing the cost of pollution and providing incentives for preventive and corrective action by firms and individuals. Individual action to prevent pollution can take many forms such as changing consumption patterns, refraining from careless acts that cause pollution, favouring the products of firms that show concern for the environment, etc. In response to public opinion, the market mechanism and government ac- tions, firms can modify their products to make the wastes more acceptable or suitable for re-use. They can also modify their production processes and 47 raw materials to minimize the generation of wastes or install treatment facilities to reduce the quantity of wastes and change their composition. PUBLIC SUPPORT Significant private or government action is unlikely to occur without public support, which is therefore essential in a comprehensive pollution control programme. Every person is concerned with environmental quality in at least three ways: (1) as a resident, subject to environmental insults and stresses that influence the "quality of life"; (2) as a consumer and user, contributing to a certain extent to en- vironmental pollution; the total cumulative effect on the environ- ment is considerable; (3) as a citizen and taxpayer, having the right and duty to express an opinion on proposed legislation and on the use of public funds for environmental protection. Public support can be achieved through a combination of means. (a) Conducting campaigns in the press and on the radio and television to produce public awareness of the problem and of the actions contemplated, proposed, or taken by the various levels of administration. (b) Developing and distributing educational material suitable for use in schools. (c) Assisting in the establishment of organizations, clubs, and asso- ciations concerned with the environment. (d) Establishing close cooperation with universities and professional organizations. The main objectives of public information campaigns are to: (1) provide information on the present environmental quality and on future trends; (2) demonstrate the interest of the Government in the preservation and improvement of the environment; (3) inform the public of remedial action being planned, its expected costs and benefits, and to raise public support for this; (4) convince all members of the public that individual actions and habits have a considerable and cumulative effect on the quality of the environment; 48 (5) ensure that education provided in schools and universities empha- sizes environmental questions and equips young people to make important decisions on such issues in adult life; (6) encourage cooperation and collaboration of professional groups, educational institutions, industrial associations, and other interested groups. Public information campaigns, to be effective, require expert planning and execution. Close collaboration between professional personnel in pu- blic information and environmental disciplines is indispensable for achiev- ing the common goal. MONITORING, FEEDBACK, AND ADJUSTMENT Environmental pollution control plans are conceived and developed in evolving circumstances, they are based on imperfect information, and they involve predictions and forecasts that contain various uncertainties. In view of the unavoidable delay between planning and execution, it cannot be expected that systems will be constructed and operated exactly as planned, that the results of their operation will be precisely as foreseen, or that these results will remain optimal under continually changing conditions. It is therefore imperative that projects should be provided with a mecha- nism for monitoring, feedback, and adjustment. (1) Monitoring. Continuous selective monitoring of the significant parameters that formed the basis of the planning and design criteria en- sures that the data and their extrapolations continue to be valid and that the programme meets needs that exist during the implementation stage. The second, equally important, purpose of continuous monitoring is to check and verify the results of the intervention, to demonstrate that the system is functioning as planned, or to permit shortcomings to be discovered quickly and adjustments made. (2) Feedback. Information produced by continuous monitoring must be collated, interpreted, and supplied to the decision-makers to enable them to draw appropriate conclusions. (3) Adjustment. The system must be sufficiently flexible to permit its augmentation or adaptation in response to new information or changing conditions. Changes in plans, designs, laws, and programmes do not necessarily result from faulty planning. As often as not, these changes are a sign that the system is viable and able to respond to the changing circumstances. The Athens Environmental Pollution Control project has made ample pro- vision for continuous monitoring, feedback and adjustment. A broad base has been established for long-term monitoring of the ecological system in 49 waters receiving wastes. The design of treatment and disposal facilities will include provision for f uture expansion. Should the on-going monitoring activities provide evidence that the absorptive capacity of the recipient water is approaching saturation addi- tional treatment units, providing for a higher degree of sewage purification, may be added as needed . This approach avoids premature investment of con- s iderable public resources while providing the flexibility required to meet future needs. Fig. 7 shows the role of the feedback and adjustment mecha- nism in the liquid wastes treatment and disposal system. PROGRAMME PLANNING AND MONITORING OF PROGRESS At the beginning of 1975 the work schedule was put on the PERT system, and four sec toral PERT schedules covering water, air, solid wastes, and noise, have been prepared . Two of these programmes - namely , the wate r pollution and air pollut ion cont rol programmes - have been transferred to punched cards and proces sed by elect ronic computer usin g a standard IBM PERT programme . The resulting output reports permit c lose and systematic control of progress and continuous adjustment of schedules according to changing circumstances. ThebuTu ants visiting nical tasks. problem dealt commendations of international expertise is provided by short-term consult- the project for short periods and having clearly defined tech- Each mission makes a report containing an analysis of the with by the consultant and including a series of specific re- aimed at the solution of the problem. Recommendations cover the entire spectrum of project activities (air, water, and noise pollution, solid wastes disposal, and environmental admin- istrat ion and legislation). They are addressed either to the project per- sonnel or to the various cooperating institutions or governmental agencies. Some of the reconnnendations are strictly technical (e.g., monitoring of cer- tain parameters and use of certain methods) while others are very broad and depend for their implementation on governmental decisions at the highest level. Most recommendations cannot be implemented without certain pre- requisites such as equipment, manpower, budgets, contracts, legislation, decisions. Finally, the actions recommended vary in urgency from those that should be implemented innnediately to those that can, or should, be postponed until future stages of the work. As it is difficult, if not impossible, to keep track of several hundred recommendations of the various types without re- course to some kind of a system, the consultan t recommendations monitoring system was developed by the Athens environmental project to assist the project management and staff in this difficult task. The primary objective of the system is to permit systematic monitoring of progress of implementation of consultant recommendations and to facili- tate implementation by timely provision of the required prerequisites. The so V, t-' Fig. 7 Data Information Decisions Action Feedback DESIGN PROCESS FOR A LIQUID WASTES DISPOSAL SYSTEM WASTES GENERATED Domestic Industrial Ll . Rain Quantity and composition of wastes generated w Type and degree ~ of treatment 1 - ' Design and construction of treatment plar.ts , RECIPIENT CHARACTERISTICS Physical Chemical ) ( Biological I t Absorptive and dispersive characteristics of recipient waters t Quality standards for effluent -, Monitoring, feedback, and adjustment mechanism + I USES OF, AND QUALITY CRITERIA FOR, MARINE WATER Recreational Fishery ] , I Others , Quality criteria for marine environment ~ Location of outfall (s) t Design and construction of outfall(s) and diffuser(s) PAI PB PCI PD1 PE PF I :::J PGI ~ PH16 lJ.J "' p I I ~ PJ n. PK PL I PM PAI PB PC PD PE [ PF :::J I = PGIS PH 0 lJ.J p I ~ "' PJ I n. PK I PL PM PUNCHED CARD S US ED 1 N TH E CON SU LTANT RFCOMMENDATION S MON1TOR 1NG SYSTE.M (',jt-l) V L.11 ,-0 (/) (/) (/) (/) (/) (/) 4 ~ U O LI.J ~ 0 I - ~ ~ ~ Z O Cl. 0 °' a:: a:: a:: a:: a:: a:: a:: a:: a:: a:: a:: a:: a:: a:: a:: a:: a:: a:: _____ AA 33SS3~00 \1 I No· IAB ~O 1 )3S IMV IAOMMhUAL POllUT IOt4 CO MIAOL PROJ . ·A THDIS PR OJ QUA RTE R pp I " . 7 ◄ - 1 74-2 7• -51 7 ◄◄ 1 co .. SULT,UU RlCOMM I MD.\TIOM S M O ... ITOlt i~ -2 75 •5 I 1s-• I 76 I 76- 2 16-5 " ·' I NAME I DATE K.E. Gronske~ 2/75 -2 17- 5 11- ◄ 78- 1 78-2 78- 5 " • I Secto r Al , ' " v!' Noise S2 I Soll d W. I s, I I Li qui d w I s• I A dmln S5 O ther S6 . Rf< OM MENOA TION • De velo p so u r ce i nven t o r y fo r s us pend ed pa r t ic ul a t e ma tte r and fo r S0 2 - / AOOREBS E E I PR E REOU I B 1T EB I T 't' ljU ! OLS A CTION I PAI O A I TV RA V Air PolluHon '.)ec lor PA Govt Purchased fqulpment A A ~ Doto Collec lion ·· VPr lo rlly ·• Noi se Abatemen t Sector PB Gov l. Emp loyed Sto l t A B Doto ln terpr eloli on Pl A RC Liquid wastes Sector PC Govt Supplied other A C Pllo l Sludles P2 B RD Sol!d Wastes Seclor PD WHO f qulpmenl AD Plonnsng P5 C RE IOKA E PE WHO tonsu l 1onls AE leglslollon NA Nol Appllcoble RF O • P PF WH .J 0 111er A F En lor cement RG Meteorologlcol lns1 PG Mlnls l er1:::tl Decision A G 1ns1ltul!on SP Superseded '" Democrnos Nucl Res Cent PH Monogertol Decision AH Manpower Developm By RI Civil A viation Au lhor Pl Leglslollve Provision Al Coo•dlnot!on RJ Monogemen1 (Pr o)ec l ) Pl Controctuo l A r rangement Al I Equipmen1 S..ippl y I I M PLEMENTATION ,, Min o t Publ le Wo r l<s PS Feos1bll!ly Stud y A K Hl,re Per sonnel RL Min. ot Tronsoorlotlon PL Recommendo11on No A l I Other Ill Preporo11on Start RM Min ol Sociot Servi CPS 1 PM Otl'ler ,, Prereq Completed RN Min. o l Industry 15 lmplementot1on RO Min o t Interior " ✓comple t ed OP Min o l Coordlnollon RO M1n ol Public Order RR Olher J AC AD AE I -< " m 0 -r, )> n --< 6 z " ~ 0 "' :::; -< AF AG A H A l IAJ A K ,A L IP I P 2 I P J NOi i V JN 3W3ldW I NA SP 0.. 0.. - N f',I') ~ lI) --0 V) V) V)V) V)(/) 4 ~ U O LI.J ~ 0 I ~ ~ ~ Z O Cl. 0 "' ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~ - ~~~~~ _~ _____ A A 33SS3~00\1 I No · IAB ~ O 1 ) 3 S U,4VIR OJ'4MUH.&L POLLU TI ON CONTROL PRO J,·ATHU 4S IPR OJ QU A RT ER PP I I " • I " ·' I 74-2 1 7• - 5 1 " • I ::: SEULT~ : ~ ~l~~~ii~; TIOJ-4 5 M0J'41TOR DA TE 75-1 I 75 -'2 \;' 75. 5 75-< [ 76 I 76- 2 76- 5 76- '4 K 8 ~at scbat I U15 77 -• I 77 -2 11 -5 I --- 71- 4 78- 1 76- 2 1 78- 5 1a , I Sector Al , ~I I I No i se S2 17 Soli d W . I " I I Liquid W I S• I I Adml n ] S5 i Other S6 Rf(OMMENDA TION • Dete r min e a Noise Ex pos ure Fo r ecas t (NEF) conto ur ma p fo r He ll inikon Ai r po rt. A O O A E SB E E RA Air Pollution ~ec tor R11 \/'Notse A botemtln l Sector •c Liquid Wostec Sector RD Solid wosres Sec lor RE !OKAE RF O AP RG Mtlleorologlco1 Jnst 'H Democrltos Nucl Res Cenl. RI \/"t.1vl1 Av1otl on Author Rl RK RL RM RN RO , p RO RR 0.. 0.. Management (Pr o)ec l ) Min 0 1 Publlc Worlcs Min. ol Trom,por lotlon Min ol Soc,ol Services Min. ol Ind ustry Min ot ln lerior Min ot Coordina ti on M,n ol Public Order Other I PA PB PC PD PE PF PG PH Pi Pl PK PL J PM ( 1 ) (2 ) P ~ E R E QU l81T EB I TY P E O P" A C T I ON Gov! Purchased fqu1pmen t A A -~ Do to Co l lecllon Govl. Employed Sto ll ( 1 A B · ·: Do to In terpreta ti on 1./'Gov l Supplied other A C PIio t Stud ies WHO Equipment A D Plonn1ng WHO C.onsultont s AE Legls loflon WH .J O ther AF Enlorcemen t Minlsterlol Dec i sion AG lns111u1lon Monogerlol Decision AH Manpower Developm Leg1slot1ve Provlslor( 2) A l Coo•dino tlon ..r'cont r oc tuol A rrongemen l Al Equlpmen1 S..ipp l y Feos1blllly Study A K Hire Per sonnel Recommendolion No A l O lher O lher Base data WHO =ntract 52 I PRI O RI T Y P l /p, ,o r lly A P2 I B P5 C N A I No t A pplicab le SP Superseded By I I M P L E M l!!! NTA TI O N 0 ,eporotion Start Il l 12 Prereq Completed 1 5 lmp lemen lotlon " Completed NOi i V JN 3W3ldW I I --< -< " ml 0 -,, )> n --< 6 z I I " ~ I 0 "' :::; -< I AC AD A E AF AG AH A l AJ A K A L p I P 2 P J I NA lsr V, w Fig. 9 ENVIRONMENTAL POLLUTION CONTROL ACTIVITY CHART• ENVIRONMENTAL DATA levels of pollutants sources of pollutants distribution in time and space levels, trends and forecasts of environmental pollution abatement strategies technical and economic feasibility analysis plans and programmes ENVIRONMENTAL MANPOWER professional technical field inspectors feedback and adjustment laboratory implementation enforcement • Shaded boxes denote activities completed or those in which substantial progress has been made. Only primary interrelationships are shown in this chart . ENVIRONMENTAL ADMINISTRATION AND LEGISLATION central planning and policy executive organs legislation environmental criteria and standards mon itoring of results secondary objective is to facilitate evaluation of certain categories of mission (as well as of individual missions) to prevent duplication of effort and to assist in planning the work of consultants. Each reconunendation is entered on a special punched card (see Fig. 8) and within a few seconds any group of cards satisfying a set of predetennined criteria can be extracted from the pack of 500 recommendations. FUTURE PROGRAMME OF THE ATHENS PROJECT The environmental pollution control project in the Athens metropolitan area commenced full operations in September 1973 and is scheduled to termi- nate at the end of 1978. As shown in Fig. 9, the first diagnostic phase of the project has been completed. During the second phase of the project a series of pollution control strategies will be defined with the aim of reducing present and the forecast levels of pollution to those corresponding to environmental policy and/or standards adopted by the country. Each strategy will be analysed and evaluated for its technical, social, and economic feasibility and its im- pact on environmental quality, land-use planning, and socioeconomic develop- ment. For this purpose, data for the cost of pollution and its abatement will be generated. The selected strategies will be refined into a series of environmental plans and programmes designed to reach predetermined ob- jectives by specified means. Legislative programmes will be develo~ed and an enforcement apparatus, including trained manpower and adequate equipment and facilities, will be built up to enable the executive bodies to perfonn the control functions with which they will be charged. A continuing monitoring activity will be maintained to test the impact of the implemented progranunes. CONCLUSIONS The comprehensive environmental pollution control project described here was designed to deal with a serious existing situation, and the pro- gress achieved and the results obtained demonstrate the validity of the basic concepts on which the project was formulated and is being executed. Experience in Athens demonstrates the general applicability of many of these concepts. 54 5. AN APPROACH TO ENVIRONMENTAL QUALITY MANAGEMENT IN THE CONTEXT OF REGIONAL PLANNING IN THE PROVINCE OF KATOWICE, POLAND C. Ferullo1 As a result of rapid economic development in Poland, especially in the Upper Silesian industrial region, environmental quality in Katowice province has been deteriorating markedly . Regional planners, alarmed at a situation that could have a serious impact on human health and wellbeing, are making assessments of existing conditions of the natural environment and in the forecasting of the con sequ ences of further indus trial developme nts within t he province. As in many other parts of the world, especially in some highly indus- trialized areas in Europe, the main sources of air pollution are energy production, metallurgic~l processes, heavy industry, cement manufacture, and domestic heating; the situation in Katowice is even worse because of the lack of space and the presence of many out-dated industrial establish- ments. In additicn, individual coal stoves are the main form of domestic heating, and most of the coal used in both industry and homes has a high sulfur content and emits large amounts of dust and gases. Recent estimates gave a total emission figure of 1 million tonnes per year of dust and about 300 000 tonnes of gases, mainly sulfur dioxide, from the industrial area of Katowice province. There has been a progressive increase in the volume of liquid waste in the area because of the increase of population in the area together with rapid economic development. It is estimated that for each 7 m3 of available water there is already 1 m3 of waste and that by 1985 the proportion will be 3 : l; in the vicinity of heavy urban and industrial discharges, and more generally during dry weather conditions, the degree of dilution of waste water is further reduced. Problems of solid wastes disposal arise mainly from municipal refuse, mining, industrial materials, and sewage sludge. It has been the general practice to dispose of such wastes on land, but suitable land is becoming scarce and vast areas have already been transformed into a "lunar land- scape" through mining and industrial tipping. Serious leaching of toxic materials, leading to pollution of surface and ground waters, has been reported. In Upper Silesia 7% of the total area has been 11sed f or dumping o[ i ron, zinc , a nd Jead o r es as we ll as s ands. 1 Regional Officer for Promotion of Environmental Health, WHO Regional Office for Europe 55 CHARACTERISTICS OF THE AREA The province of Katowice, situated in the south of Poland, covers an area of 6 686 km2 and has a population of 3 439 000, representing 2% of the surface area of the country and 10% of the total population. The province lies in the heart of the Upper Silesia industrial region, one of the largest industrial basins in E11rope, the economic potential of which influences to a large extent the life of the region and the quality of the environment. The average density of population is 514 inhabitants per km2 , the highest in the whole country, reaching up to 4500 in urban centres. Alto- gether, 18% of the country's industrial production and 98% of its coal pro- duction is concentrated in this region. Water resources are only 600 m3/ inhabitant per year by comparison with an average of 1650 m3/inhabitant per year for the whole country. Nearly two-thirds (62%) of the total length of rivers in the area do not meet the national water standards while the emission of dust and gases is 36% and 24%, respectively, of the estimated total emissions in Poland as a whole. SETTING OF GOALS The Government of Poland, havin g recognized the urgent ne ed for im- provement of environmental quality in the area, made a joint effort in col- laboration with the United Nations Development Programme (UNDP) and WHO to solve the problem by concentrating all available resources in a model area selected in the most densely populated and highly industrialized part of the province. The preparation of a comprehensive plan for environmental pro- tection was entrusted to a newly established institution in Katowice named the Environmental Pollution Abatement Centre. The Centre was created by the Ministry of Land Resources Environmental Protection and Administration under the UNDP/WHO project and the building to house the Centre was com- pleted in January 1975. OPTIMIZATION AND FEASIBILITY Two approaches to the solution of the problem were considered at the planning stage: (1) the optimization approach, implying construction of models related to one another and interacting in the fields of land, water, and air quality management, and (2) the conventional approach to solving the problem in the three separate fields, disregarding their interrelation- ships. The optimization approach was considered the correct one for the following reasons: (a) the existing agreement between the Government and the international organizations that the comprehensive plan should be based on "the optimum mix of strategies" according to the most modern and up-to-date technologies and following the design and establishment of a compre- hensive information system; 56 (b) the desire and determination of local authorities to obtain the best possible solution to the very complex problem of environmental control; (c) the increase in resources available to the province for investment in the field of environmental protection during the new 5-year plan (1976-80); (d) the existence of a nucleus of well trained, multidisciplinary staff covering the fields of air, water, and solid wastes at the Katowice Environmental Centre ready to devote most of its time to find- ing original solutions to environmental problems, with assistance from UNDP and WHO. It was also recognized that a multidisciplinary approach in the inter- related fields of air, water, and solid wastes management would create a better understanding of the whole system and foster a t eam spirit approach among the participants. Finally, the establishment of a comprehensive monitoring system would allow the correction of inevitable errors as well as adjustment to possible changes in technologies and external conditions. However, because of the limited life-span of this joint venture - 5 years - it was thought wise to apply the optimization technique to one part only of the territory of Katowice province in which all the various environmental problems were represented, and to extend activities to the rest of the pro- vince at a later date when enough experience had been gained. CONSTRUCTION OF THE MODELS At the present stage of development of the models, it is useful to deal separately with those for air, water, and solid wastes, introducing a number of indicators suitable for this purpose. However, keeping in mind the aim of integrating the results to obtain an optimum overall plan, the next stages in this process are outlined for each of the models. First, the origin of the different elements affectin g the air, water, and land environment is considered by selecting some of the indicators such as pollutant emission sources for the air component, organic discharges in rivers for the water component, and solid wastes discharges for the land component. Next, the relationship between those elements and the quality of the environment (air, water, and land) is determined and compared with existing standards, as in the case of air and water pollution control, or with the operative goals of limiting soil disruption and compensating for existing disruptions in the case of land protection. 57 The pattern of the overall environmental quality management model is illustrated schematically below. Limitation of damage to the environment Development and application of techniques Existing standards Environmental quality management Environmental quality models Air Quality Management Inventory of residual discharges in the model area Restoration of disturbed environment Cost/benefit analysis The latest inventory of dust a,1d gaseous pollutant emissions is sum- marized below (quantities expressed in 106 kg/year) . Township Dust S0x N0x Gliwice 13 . 4 5.9 1.2 Zabrze 46.0 17.3 5.2 Bytom 39.0 23.1 5.0 Ruda Slaska 39 . 4 38 . 7 11.6 total 137 . 8 85.0 23.0 Pollutant emissions are mainly the result of discharges from : - domestic heating; - coke industry; - metallurgical industry (ferrous and nonferrous metals); - chemical industry; - power plants; and - factories producing building materials. 58 Construction of the dispersion model Construction of the model is based on the diffusion model used for es- timating statistical distributions of instantaneous concentrations according to the Pasquill point source Gaussian formula. Its output being instanta- neous rather than average concentrations, calculations are performed for the fundamental wind direction rather than with the 16 wind directions used in the mean seasonal concentration model. Actual meteorological data have served as a basis for elaborating the probabilities of a combination of ventilation conditions (wind speed and direction) and atmospheric stability classes. In the model area wind speed is generally below 2 m/s and stable air equilibrium is present for about 40% of the time in a year, with neu- trality and instability representing 36% and 24%, respectively. The model takes the form of an equation whose structure is of the type: AAQ = f (X., Y.), 1 J where AAQ is ambient air quality measured by the concentration of pollutants such as dust and S02; Xi are the variables that can be controlled, Yj the variables (and constraints) not controlled, but influencing, ambient air quality . The relationship between AAQ and the variables is expressed by f. Separate formulas have been developed for dust and S0 2 of the general type illustrated above and susceptible to solution by linear progrannning. The main variables include: H u k = diffusion coe f ficients along the direction y and z; they are a function of the distance from the source and the stability class 2 effective emission height in metres = average wind speed, (m/s) = pollution decay coefficient Data have been collected from 345 emitters for 32 major pollutants con- sidered as point sources. Area sources are mainly due to domestic heating . Considering two of the main components of air pollution, dust particles and S02 , it was found that industry is responsible for 80% of the emissions, domestic heating for 8%. The air pollution abatement plan The first objective of this plan is maximum reduction of dust emission from the most important plants by renewal of existing dust-removing equip- ment or installation of new equipment , according to prevailing technical possibilities . This will represent the first stage of the action plan and will be followed by a second stage with further reduction of atmospheric pollution to values not exceeding the highest allowable concentrations in- dicated in the national standard. Activities considered under the plan are : metallurgical industry, 6 steel mills 59 coking process, power plants, domestic heating, 7 coke plants 4 power stations 4 townships (Gliwice, Zabrze, Bytom, Ruda Sl.) Studies were made for each plant to determine the types and frequency of pollutants and their origins at different stages of the processes. A summary of the results is given in the table below. Emissions (tonnes/year x 106 ) from selected industries Present levels After implementation of first phase After implementation of second phase I Bytom Gliwice Ruda Sl. Zabrze total I Bytom Gliwice Ruda Sl. Zabrze total I Bytom Gliwice Ruda Sl. Zabrze total Tonnes of particles 54 446 4 405 20 975 41 324 121 150 14 464 2 580 16 613 4 212 37 869 11 833 929 9 585 3 983 26 330 Optimization strategies based on dynamic programming Polish standard: 250 t/km2 per year Percentage reduction 73.43 41.43 20.80 89.81 68.74 78.27 78.91 54.30 90 . 36 78.27 As mentioned above, there are several ways to improve air quality in the model area. For each solution it is possible to calculate the cost that will produce a reduction of pollution meeting the required standards. Computations are not recorded here, only procedures based on the technique of dynamic programming. Given four types of option aimed at meeting the Polish air quality standards, we can establish a relationship between the cost involved and the reduction in pollutant concentration achieved. The relationship is expressed by an equation of the type: 60 where c1, c2, ... Cn are the costs associated with each of the proposed allocations of resources, keeping in mind that: c1 + c 2 + ..• cn = A, where A is the overall allocation to be determined in advance. If we consider four options, the relationship can be represented by four curves showing the increasingly higher costs associated with increas- ingly higher percentage of reduction in pollution levels. i:: 0 "M .w c.J ::, "O (lJ H (lJ 00 C\l .w i:: (lJ c.J H (lJ p.. Cost technological changes cleaning equipment modernization of plant improvement of domestic heating systems The optimal combination of these four strategies offers the maximum possible reduction for a given total cost or total allocation (A). Applying the Bellmann algorithm to the dynamic programming, we obtain: F (x1 , x2 , x3, x4) = f1 (x1) + f2 (x2) + f3 (x3) + f4 (x4) , To obtain: we proceed step by step in the following manner. (a) Calculation of F1,2 (A), that is, the optimal allocation to apply the first two techniques for pollution abatement, F1,2 (A)= max [f1 (x) + f2 (A - x)]. (b) Calculation of F1,2,3 (A), that is, the optimal allocation applied to the combination of the first three techniques, F1,2,3 (A)= max [F1,2(x) + f3 (A - x)]. 61 (c) Calculation of F1,2, 3,4 (A), that is, the optimal allocation where ail four techniques are applied, F1,2,3,4 (A)= max [F1,2,3 (x) + f4 (A - x)] . It is clear that the maximum of f1, f2 for the particular value of x1 and xz must satisfy the relationship A= x1 + xz when calculating the func- tion Fi 2 of A. Similarly, the relationships A= x1 + xz + x3 and A= x1 + x2 + x3 + x4 have to be respected in the calculation of the maximum of F1, 2 and f 3 and of the maximum of F1, 2 ,3 and f4, respectively. Water Quality Management Inventory of residual discharges An inventory of residual discharges including organic pollution, sus- pended solids, and salinity has been completed for the river basin of Klodnica from its source to the western boundary of the township of Gliwice. This river is a recipient of: (1) domestic sewage, and (2) waste water from 16 coal mines, 5 steel mills, 7 coking plants, 4 power stations, and around a dozen other industrial activities . For the purpose of model construction, the following indicators were selected: BOD5 to measure organic pollution, (tonnes/day) - suspended solids, (tonnes/day) - chlorides and sulfates for salinity, (tonnes/day) . Results of the latest inventory (1974) and a forecast of pollution levels in 1980 and 1990, respectively, are given in the table below. B0D 5 suspended solids chlorides sulfates Model for the Klodnica River 1974 28.7 47.2 585.1 196.4 1980 34.2 69.9 682.1 233.3 1990 22.5 47.6 700.6 220.5 A monitoring network including 19 flow-gauging stations in the river and 54 stations located at tributary and effluent outlets was established and the river divided into reaches to be incorporated into the model struc- ture. The points were selected on the basis of past experience in relation to water flow or quality variations. 62 To reproduce longitudinal dispersion, variations of flow over time have been calculated on the basis of recorded time of travel, flow rate, velocity, depth of water, and river width. Parameters of longitudinal mixing were calculated by different methods to select the one that would give the best approximation to observed flow, comparing theoretical results de- rived from the model with those obtained by experiments with a coloured tracer. The figure below illustrates the results of this comparison and shows the accuracy of this model when estimated and observed concentrations of dye (rhodamine B) are plotted against time. In spite of the rather compli- cated hydraulic conditions due to irregularities of the river, a reasonably good fit is obtained. 0 Q) 0 >, 0 '"O 0 4-< 0 i:::: 0 0 •.-i .µ 0 co i-.. .µ i:::: Q) u i:::: 0 u 0 0 0 0 0 0 0 0 LI') 00 ,-; -er ,-; ,-; N N 0 0 0 0 r-- 0 N (") 63 Concentrations o measured , calculated Velocity, 0.238 m/s 0 00 0 0000 o 0 Time (s) 0 0 0 0 0 0 - (") '° °' (") (") (") At the beginning of the study, two types of model were considered: (1) a model of a self-purification process based on the assumption that the flow can be represented by a series of blocks moving down- stream; (2) one- and two-dimensional models of self-purification and disper- sion processes represented by a second-order differential equation. After further investigation, model (1) was chosen to represent the processes occurring in th e Klodni ca River, while mode l (2) was developed from the methodological point of view only. Waste water treatment Municipal and industrial discharges in the Klodnica River include large amounts of suspended solids, organic compounds, and salts as well as toxic substances such as cyanides, phenols, and metal compounds. To solve the problem of suspended solids, two different methods have been considered: (1) mechanical treatment of waste water containing only inorganic suspended solids, and (2) treatment of waste water containing inorganic as well as organic suspended solids. Mechanical treatment includes screens, grit chambers, and grinders; biological treatment includes activated sludge and equipment for sludge treatment by digestion and drying processes. Altogether, five methods have been studied and their respective efficiencies calculated. Efficiency of removal Method Suspended BOD5 solids simplified biological without primary settling 0.70 0.65 partial biological with primary settling 0.76 0.76 complete biological, high efficiency 0.90 0.88 complete biological, very high efficiency 0.95 0.95 two-step biological, highest efficiency 0.97 0.97 A combination of the various methods has been devised to achieve the standard required for the Klodnica River. For the main effluent, the Bytomka, it has been calculated that 1642.2 million zlotys (about 33 million US$ at the rate of 1 US$ to SO zlotys) are needed to remove 72% of suspended solids and 88% of BOD5. For the elimination of industrial discharges, such as oils and metal compounds, biological and chemical treatment have been considered. It was found that chemical treatment processes are the most suit- able for treatment of waste water containing metals. The cost of treating metal discharges from a complex of three large industrial plants has been worked out on the basis of existing literature. If treatment is to take place in a single plant dealing with a daily average of 100 000 m3 of waste water containing metals, the capital cost of the chemical plant will reach 182 million zlotys (about 3.6 million US$). 64 Highly saline water is discharged by three coal mines and by minor sources, most of it reaching the Klodnica River. The salinity level of underground water varies within the ranges of 60 mg/litre to 27 500 mg/litre for chlorides and 80 mg/litre to 13 100 mg/litre for sulfates. Screening of moderately saline underground water has been considered and an economic study to determine the cost of such an operation is under way. Disposal of Solid Wastes Inventory of existing situation and future forecast Municipal wastes. During the period 1972-74 an inventory was estab- lished for the model region and the results reported for each at the four townships were as follows: Bytom Gliwice Ruda Sl. Zabrze total m3 X 10 3 216.0 239.2 181.2 269.3 905.7 Municipal wastes are mainly disposed of by uncontrolled tipping; con- tinued urban growth makes any other way highly impracticable. In fact, it has been estimated that the ~resent rate of waste generation of 1.3 m3 ~ capita/year will yield 2.3 m in 1990, when the total amount of waste pro- duced will be approximately 1700 x 10 3 m3/year. The optimization study undertaken by the project will serve as a basis for the decision-making process to select the best collection and disposal method. Industrial solid wastes. Altogether, 19 million tonnes of wastes have been produced in the model area in 1975, 87% originating from coal mining, 9% from iron and steel metallurgy, and 2% from powe~ industry. Increased waste production is expected and current estimates are 22.5 million tonnes in 1980 and about 24 million tonnes in 1990. In 1975 there were about 760 hectares of tipping sites, of which 503 ha were refuse heaps for coal mining, 91 ha for metallurgical industry, 128 ha for mining and pro- cessing of zinc and lead, and about 40 ha for waste heaps originating from power plants. In spite of increased waste production it is expected that by the year 1990 waste heap areas will be reduced to 140 ha, thanks to better disposal methods and, especially, to recycling. Other solid wastes. Other wastes result from activities connected mainly with local ceramics and building industry. The waste lands include sand excavations, quarries, and clay pits. In 1975, a surface of 153 ha was used for such operations. It is expected that the surface will be reduced to 68 ha by 1980. 65 Establishment of a model Municipal wastes. In the absence of a dispersion model similar to the one established for air and water it was difficult to decide on a methodology for wastes management in the model area. As an experiment, the area was divided into subareas and it was assumed that each subarea was the origin of production of wastes (expressed in tonnes per week). These units of measurement were applied to the location of transfer stations and final discharge points (tipping sites, incinerators, composting plants). Next, all possible relationships (from collecting point to transfer stations, from collecting points to final discharge points, and from transfer stations to final discharge points) were determined. Costs (expressed in zlotys) include: collection cost, transport cost, transfer operating cost, and final discharge point operating cost. Computer calculations were used to determine which unit should be built and where, as well as quantities of waste to be transported on particular routes. Finally, the computer gave the total cost per week for the performance of the entire system. Deter- mination of a proper location for tipping sites was the first stage of the study. No location within the model area was found suitable for a tipping centre. After a survey of the vicinity, it was found that the most suitable location was a large area of waste land north of Bytom, having an estimated capacity of 10 million m3. Having selected this point, it was found that the furthest points of waste collection furthest apart in the model area are 30 km from the proposed tipping site, hence it was necessary to install a two-step transport system using transfer stations. It was agreed with the authorities that various alternatives would be proposed for 4 transfer stations, 6 incineration plants, and 2 composting plants. Industrial wastes. As in the case of municipal waste, in the absence of an environmental pollution dispersion model selection of alternative solutions for proper disposal could not be based on environmental quality standards. Optimization studies were based on the assumption that high priority will continue to be given by the Government to industrial waste recycling, and all activities were directed towards the establishment of technologies to meet this objective. The criteria for selection between different methods will be minimization of cost including investment required, land value, transport cost to consumer or tipping site, and cost of tipping. Optimization techniques cannot be generalized because they are depen- dent on the solution accepted for each particular type of industrial waste; among these, coal mining wastes have been given higher priority. Five types of application have been considered in the study: filling excavations, filling exploited mine areas, treatment by special methods, production of building materials, and transformation for use in engineering works. After coal mining wastes, studies were carried out on treatment and utilization of wastes from power plants, iron and steel metallurgy, and non-ferrous metallurgy, these being the main activities having an effect on the environ- ment in the model area. 66 INTEGRATED REGIONAL OPTIMIZATION The purpose of integrated regional optimization is to determine for the model region the minimum-cost strategy required to meet, simultaneously, the ambient air and water quality standards. It has been stressed that detailed studies on the physical relationships between the three components are needed, that identical planning periods must be used as a time base, and that costs must be determined with consistency. For instance, for all three groups of wastes cost estimate should be based on the same breakdown: investment, operation, maintenance, and amortization. This has been done for solid wastes and is now under consideration by the groups concerned with air and water. Integration of the three separate optimization models and the specifica- tion of environmental quality management strategies applied t? the model region is the responsibility of a newly created team in the Environmental Pollution Abatement Centre under the direction of the Centre's scientific coordinator. This team is also responsible for the preparation of all studies required before starting the planning, implementation, and enforce- ment phases. RELATIONS BETWEEN ENVIRONMENTAL QUALITY MANAGEMENT AND REGIONAL PLANNING The subject of conflicting goals in the double task of regional and environmental planning was discussed during an international seminar on environmental pollution control in the context of regional planning held in Katowice under UNDP/WHO sponsorship in October 1975. It was recognized that in some cases economic development opportunities for this generation could conflict with the idea of preserving natural environmental resources for future generations. The Katowice plan will be based on a model showing what value structures are applied to determine priorities and to resolve goal conflict; it will also indicate the best ways to distribute economic and investment activities within the region, taking into account all the requirements related to environmental protection. The model area selected for the optimization study and the implementa- tion plan that will follow is a prototype for other parts of the Upper Silesian industrial region. The same authority will be responsible for both environmental quality management and regional planning and this should assist in preventing conflicts between goals. It will be necessary to make some allowance for the spatial distribution of air and water pollution, which overlap administrative boundaries. 67 SUMMARY AND CONCLUSION 1. An optimization study for a mode l r egion within the Katowice province in Poland is being carried out by the Polish experts with UNDP/WHO technical and financial assistance. This will serve as a basis for preparing an environmental protection programme to be considered within the frame of the regional plan. 2. The studies include establishment of three separate optimization model s for air, water, and solid wastes, later to be integrated for the specification of environmental quality management strategies taking into account adminis- trative, legal, and economic aspects related to the implementation of the regional plan. 3. It is expected that the Katowice model will serve to demonstrate the possibility of harmonizing environmental health objectives with more general aspects of regional planning. SELECTED BIBLIOGRAPHY Environmental Pollution Abatement Centre , Katowice. November 1975 (document POL/CEP OO1/UNDP/71/511) Interim report . Mauch, S.P. Report on a seminar and workshop on environmental pollution control in the contex t of regional planning. Katowice, Environmental Pollution Abatement Centre, 1975 United Nations Economic and Social Council, Economic Commission for Europe. Proceedings of a Seminar on national and regional planning as a framework for local planning, Helsinki, May/June 1975 (HBP/SEM . 7/3-1O June 1975) 68 6. POLLUTION CONTROL IN A LARGE RIVER BASIN T. Murawski 1 THE HUNGARIAN WATER QUALITY PROJECT A 5-year project, Pilot zones for water quality management, which is being implemented by the Government of Hungary with UNDP/WHO assistance is intended to serve as a prototype for a national water quality improvement programme and provide a rational basis for the necessary capital investment. Two pilot zones were established in 1972. One zone covers a 140-km sector of the Danube above Budapest, the other the Hungarian reaches of the Sajo, which flows into the country from Czechoslovakia. Thus, simultaneous studies could be carried out on the largest watercourse in the country, supplying water to Budapest and passing through the heart of the city, and on a heavily polluted tributary. Physical and economic models of the pilot zones of the D~ube and the Sajo rivers are being developed. As water quality in both zones is affec- ted by sources of pollution outside Hungary, problems connected with inter- national coordination of water quality control programmes are also being studied. The project includes studies on sampling and analysis (including automated methods), optimization studies on effluent discharges, river self- purification, effluent treatment requirements, adaptation of new waste treat- ment technolo gies to Hungarian conditions, and the establishment of regional water quality control schemes including legal and administrative aspects. The project for the Sajo River pilot zone has now been completed and includes the preparation of an integrated engineering/economic water quality management model and optimum investment plan for the Sajo region. The objective of the work in the pilot zone along the common Hungarian/ Czechoslovak reach of the Danube is to study water quality in this complex hydraulic system and determine conditions and substances that affect water quality in the Hungarian zone, with intensive study of micropollutants and of lateral and longitudinal mixing and self-purification characteristics of the river. Owing partly to the presence of islands in the river, there is a marked difference in water quality across different sections of the Danube. This is particularly important from a public health point of view when ab- stractions for public supply are under consideration. The work also includes a study of urban stormwater run-off in Budapest. l Project Manager, UNDP/WHO Project HUNGARY PIP 001. Present post: WHO Consultant in water quality management. 69 It is expected that the study of these two pilot areas will make important contribution to proposed investigations covering the entire catchment area (see accompanying map). GENERAL CHARACTERISTICS OF THE DANUBE BASIN an Danube The Danube drainage area comprises 817 000 km2 , or approximately 8% of the European continent. The river itself is 2857 km in length and approxi- mately 70 million people dwell within the catchment area (see Table 1) . The river passes through or forms the boundary of eight countries: Austria, Bulgaria, Czechoslovakia, Federal Republic of Germany, Hungary, Romania, the USSR, and Yugoslavia . It also receives water originating from four other countries, Albania, Italy, Poland, and Switzerland (see map). At present, the Danube is considerably less polluted than the Rhine, for example, but there is now concern about recent deterioration in water quality . The river is a vital, multipurpose resource for drinking-water, industrial water, navigation, energy production, irrigation, fisheries, and recreation. Im- poundments for hydroelectric power are changing the regime of the river, allowing accumulation of sediments that in some reaches concentrate critical amounts of toxic metals. Although the Danube has a great capacity for self- purification in respect of sewage and other decomposable organic wastes, these have considerable local effects; the effects of bioresistant materials are much more widespread. Future economic development along the river will be accelerated by competition in the 1980s from the 3500 km Rhine-Main-Danube transcontinental canal, which will join the Atlantic to the Black Sea. This will undoubtedly result in fur ther problems of water quality in the Danube. HYDROLOGICAL ASPECTS OF THE DANUBE The Danube's water regime upstream of the River Inn confluence is rela- tively balanced: a fundamental change takes place from the entry of the large flow of the River Inn and the smaller flow of the rivers Tran and Enns. Downstream of the Inn confluence the Danube t akes on an alpine charac- ter, which is changed by the effects of the Drava, Sava, and Tisza rivers, which join the Danube lower down. A few km upstream of Bratislava, Czecho- slovakia, the river loses its alpine character . Some data on the water regime, partly at the confluences of major tributaries, are given in Table 2. The annual average volume of flow is 44 krn 3 at Passau, 74 km3 at Budapes t, and 200 km3 at the Black Sea. At high flows the whole stretch of the Danube from Ulm, Federal Republic of Germany, to the mouth is navigable. As regards the sediment regime, bed-loading is characteristic of the upper part of the Danube while a suspended load is characteristic of the downstream reach of the river. Downstream of Bratislava some 0.6 million tonnes of gravel per year have to be dredged; the suspended load, which annually averages in the middle part of the Danube up to 5-6 million tonnes, increases at the river mouth to 60 million tonnes/year (1). 70 -.J I-' THE DANUBE CATCHMENT AREA ~ !<Ye., rv<i5t q, _,._',>' ~~~ <,_'<--* (j ; .... IT A Ly ' . .' POL4 N o -·-... I _; ·-•,,- , . J · . .:_ ·"" YvG06L4VIA ALa..i,,.,14 _; -' ·' I .' I I I i I\ 0 IA P. N I A Source: International Atomic Energy Agency (5). us s -9 ,:J V) c'5 ... ii5' Table 1 CHARACTERISTICS OF THE DANUBE CATCHMENT AREA1 Area of Proportion of Population of Proportion of Bank Country country Danube catchment country Danube catchment length (thousands of (thousands km2) of km2) (%) (millions) (millions) (%) (%) Austria 84 83 99 7 7 100 12 Bulgaria 111 50 45 8 3 50 7 Czechoslovakia 128 69 54 14 7 50 3 --.J Federal Repub- 248 51 20 58 10 17 23 N lie of Germany Hungary 93 93 100 10 10 100 12 Romania 238 233 98 19 19 100 24 USSR 22 402 42 0.2 226 1 0.4 2 Yugoslavia 256 183 71 19 13 68 17 -- 1 Data are rounded up and proportions are estimated since national statistics do not contain such a break-down. Source of data: Research Institute for Water Resources Development (VITUKI), Budapest (10). Table 2 WATER REGIME OF THE DANUBE IN SOME CHARACTERISTIC RIVER SECTIONS1 Catchment area Characteristic flow (m3/s) Specific runoff Water-level Section fluctuations (thousands of km2) Low Mean High (1/s/km2) (m) Inn (upstream) 50 180 730 7 000 25 8.3 Inn (downstream) 76 470 1 430 8 700 28 9.3 Vienna 102 390 1 920 10 500 17 8.3 Bratislava 131 630 2 080 10 800 16 8.7 Budapest 185 650 2 340 9 500 13 7.9 -..J w Orsovii 576 1 800 5 600 16 000 10 7.0 Oltenita 690 1 910 5 940 16 580 9 8.8 River mouth 817 2 000 6 430 19 200 8 1 Data source: Research Institute for Water Resources Development (VITUKI), Budapest (10). Construction of river barrages on the upper part of the Danube (Austria, Federal Republic of Germany) has caused considerable changes in the sedi- ment regime, especially in backwater reaches where the major part of the bed-load settles out and must be removed by regular yearly dredging. Major changes in the water regime as well as the sediment regime may be expected when the Rhine-Main-Danube canal, and the joint Czechoslovak/ Hungarian hydraulic energy base (Gabcikovo-Nagymaros; output 846 MW) are completed. Changes in slope conditions and in the components of flow velo- city, affect the distribution of suspended solids, water transparency, and temperature, and consequent changes in the decomposition of organic matter in the whole biological ecosystem are to be expected (2). FUTURE ECONOMIC DEVELOPMENT AND PLANS FOR DANUBE WATER USE Public water supply The Danube is an important source of public water supply; for example. Budapest draws more than 1 million m3 of water per annum from the river. There has been a significant increase in per caput consumption during the last two decades and this trend is expected to continue. Most domestic sewage is discharged into the river virtually without treatment. Industrial water usage Large volumes of water from the Danube are abstracted by industry both for process requirements and for cooling. Major users include pulp and paper plants, chemical works, oil refineries, iron and steel works, and food manufacturers. Effluents from these industries are almost all returned to the river. Agricultural irrigation About 1.3 million ha of land are now irriga ted from the river. The areas requiring irrigation will reach about 2 .7 million ha by 1990 (see Table 3). Estimates made by Welev (3) indicate that by the end of this century the area irrigated from the river could reach 4.2 million ha with a water demand (during the growing period) of some 16.4 x 10 9m3 of water. Navigation The river is an important commercial waterway; the volume of goods carried is at present some 100 million tonnes and is steadily increasing. The Rhine-Main-Danube canal to be opened in the early 1980s will pro- vide a waterway to the Rhine area with a population of around 160 million. This waterway will affect, directly or indirectly, the interests of states with a total population of 240 million. The rate of urban, and especially industrial, development has already increased along the completed section of the Rhine-Main-Danube canal, and experience gained elsewhere indicates 74 Table 3 FUTURE AND PRESENT AREAS UNDER IRRIGATION IN THE DANUBE COUNTRIES 1 Austria Bulgaria Czechoslovakia Country Federal Republic of Germany Hungary Romania USSR Yugoslavia Total 1 From Liepolt (9). 1990 estimate (ha) 49 000 731 200 240 000 unknown 321 550 1 003 900 unknown 300 000 2 645 650 at present (ha) 49 000 143 800 240 000 100 245 800 600 000 unknown 100 1 278 800 that economic growth along such waterways is often higher than that esti- mated after the project comes into use. It can be assumed tbat the con- struction of river barrages on this waterway will have also considerable effect on the development of industrial plants, oil refineries, chemical works, etc., in the Danube riparian countries. Estimates in4icate that the total volume of goods carried on this waterway will reach some 190 mil- lion tonnes in 1990 (1). Moreover, the feasibility of a Danube-Odera canal is now being considered. Energy production Hydroelectric power. The mean flow of the river discharging into the delta is 6500 m3/s and there is a fall of 700 m within its navigable reaches. This represents a major source of energy that is increasingly being utilized. In 1972 the Iron Gate hydroelectricity generating station (2050 MW), built jointly by Romania and Yugoslavia, one of the largest in the world, was commissioned. Now, the construction of an additional barrage at Calafat, Romania, has been agreed, and two further barrages on the common Bulgarian- Romanian reach of the Danube are in the planning stage. Romania is con- tinuing work also on the construction of a canal linking Cernavoda with Constanta (on the Black Sea). It has recently been decided jointly by Czechoslovakia and Hungary to construct . two more hydroelectricity plants (Gabcikovo-Nagymaros). 75 The Danube has a total potential capacity of 7660 MW in a normal year, 48 hydropower works produce some 42 600 GW.h of electrical energy (4); 18 power stations with a capacity of 3253 MW are now producing some 17 330 GW.h electrical energy, i.e ., 41% of the total Danube hydropower potential. Nuclear energy. Seven small nuclear power stations using Danube water are already in operation; Austria operates one station of 0.7 GW (net) in- stalled nuclear capacity, Bulgaria has three stations of 1.32 GW, and the Federal Republic of Germany 3 stations of 1.2 GW capacity . Under construc- tion in Hungary is a nuclear station (Paks) on the Danube with an initial capacity, by 1979, of 0.44 GW, to be extended by 1980 to 0.88 GW with the possibility of further enlargement . A study made by the International Atomic Energy Agency (IAEA) on the growth of nuclear power capacity in Danube countries estimated that by the year 1980 some 10, and by 1985 some 21, nuclear reactors would have been constructed (5). The forecast for the year 1995 is more than 76 reactors, and for the year 2000 more than 110. Fisheries The major commercial fisheries are in the lower reaches of the river and the estimated catch, including that from ponds and lakes in the flood- plain and in the delta, is estimated to be about 50 000 tonnes per annum. Table 4 provides figures for the Danube countries. Table 4 1 COMMERCIAL FISHERIES IN THE DANUBE1 Country Austria Bulgaria Czechoslovakia Federal Republic of Germany Hungary Romania USSR Yugoslavia Total Catch (tonnes/year) 100 600 350 100 450 1 100 900 700 4 400 The average commercial catch is 4400 tonnes annually, shared among the riparian states as shown. In addition, 45 000 tonnes, mainly cyprinids, are caught in ponds and lakes in the floodplain and in the delta. From Liepolt (9). 76 Recreation The river is an important recreational resource for both residents and tourists, from the wooded valleys of the upper reaches to the quiet wild- life sanctuaries of the Danube delta. Boating, bathing, and fishing are enjoyed by increasing numbers of people in the Danube area. Besides the present uses, it is also expected that a fairly large amount of the river water (approx. 200 m3/s) will be transferred to other water systems. These projects are the canals that will connect two international river systems (e.g., Rhine-Main-Danube; Danube-Odera-Elbe), or the rivers and the sea (e. g., Danube-Morava-Varda r-Aegean Sea). All these rapidly increasing wate r uses cause degradation of the Danube River water, and it is of mutual interest to the riparian states to protect water quality in the river system. COORDINATION OF WATER POLLUTION CONTROL PROGRAMMES IN THE DANUBE BASIN All the riparian countries are engaged in prograurrnes of water quality surveillance, but there is growing realization of the need for more infor- mation about the river as a whole, its capacity for self-purification, and the fate of specific pollutants as they pass downstream. As problems in- crease with rapid industrial and other developments, a coordinated study and assessment of river water quality is becoming a matte r of primary im- portance to all riparian states. The work already carried out by the WHO Regional Office for Europe in a number of riparian countries has clearly shown that collaboration in this regard is necessary and would be advantageous to all countries concerned. Five of the eight riparian countries have carried out, or are carrying out, UNDP/WHO-supported environmental control projects. In three countries (Czechoslovakia, Hungary, and Romania), UNDP and WHO are collaborating with national governments on projects that include investigation of pollution in the Danube; in Bulgaria, UNDP and WHO have assisted in the establishment of a Scientific Centre for Hygiene and Epidemiology, whose activities in- clude assessment of Danube _water quality. In Yugoslavia, a UNDP/WHO proj- ect involving water pollution is in progress on a tributary of the Danube and another is planned to start in 1977 concerning the effects of industrial water pollution in Bosnia. The Regional Office for Europe, with assistance from the United Nations Environment Programme (UNEP), convened a workshop in Copenhagen in March 1975 on the study and assessment of the water quality of the Danube. This was attended by participants from Austria, Bulgaria, the Federal Republic of Germany, Hungary, Romania, and Yugoslavia, as well as by representatives of international and nongovernmental organizations. The report on the workshop contains firm recommendations concerning the water quality of the river. 77 The Regional Director, Dr Leo A. Kaprio, re fer red t o a r eq uest by the Twenty-fif th World Health Assembly in 1972, requesting the Director-General of WHO to promote collaboration among countries on the protection of inter - national water resources against pollution (8) and also to Recommendation No. 77 of the United Nations Conference on the Human Environment, which, in particular, entrusted WHO and other relevant agencies with developing inter- national monitoring programmes in collaboration with governments . He ex- pressed WHO ' s willingness to help in the development of joint studies of water quality in the Danube basin and to collaborate with other organizations so as to make available to the Danube countries any specific expertise that might be at the disposal of these organizations. Such efforts will cer- tainly be needed in the immediate future to prevent the water quality of the Danube from deteriorating with increasing rapidity (6). PROPOSALS FOR AN INTERCOUNTRY PROJECT WITH WHO ASSISTANCE In view of the need to coordinate efforts, and recognizing the inter- national character of the task, proposals for an intercountry, WHO-assisted project have been formulat ed. Objectives have been established, work plans drafted, and a timetable for project implementation drawn up. Two phases are envisaged: a preliminary phase to carry out preparatory activities un- til the end of 1977, and a second phase in which the project would be fully developed. A summary description of the main features of the projects is given below. Long-term objectives The project is intended to assist riparian governments in acquiring a basis for rational decision-making on measures necessary to improve and maintain Danube water quality. Although the project has no direct invest- ment potential for external financing, it is nevertheless expected that the results will greatly contribute to the rational utilization of the consider- able investments of the governments concerned in their long-term programme for water quality management of the river Danube and its tributaries. Immediate objectives (1) To receive adequate comparable data on a continuing basis and to ensure its coordinated evaluation; (2) to provide an assessment of the present state of the Danube and its major tributaries as well as of future trends in water quality; (3) to assist in investigations of the dispersion and diffusion of important micropollutants and, inter alia, their transformation and degra- dation through self-purification processes; (4) to assist in studies of the determination of the self-purification capacity in reaches of the Danube and its major tributaries of concern to the riparian countries; 78 (5) to assist in the selection and adaptation of waste treatment pro- cesses and technologies according to local conditions; (6) to assist each government with additional complementary studies and investigations in areas of water pollution control that are important to individual countries; (7) to provide specialized training in various aspects of water pollu- tion control. Institutional framework It is expected that governments will designate specific ministrie s or central authorities as cooperating agencies that will be directly responsible for the implementation of the governments' contributions to the project. Governments will be encouraged to centralize their data handling programmes, where they have not done so already, and to designate reference laboratories to provide advice and guidance in standardization of sampling and analytical techniques. Such laboratories and data centres could be recognized by WHO as collaborating centres for the water quality monitoring programme, and in- tegrated in a regional system to facilitate exchanges of data and informa- tion on methodology. Thus in each of the participating countries one or more scientific institutions will be chosen as national reference centres that will cooperate with the project to secure maximum coordination of effort. International collaboration will be developed by frequent meetings in- volving specialists from participating countries. It is envisaged that a scientific council having members from each of the countries, will be estab- lished to guide the implementation of the programme. The national reference centres will, when necessary, give specific research work and studies to other organizations on contract, but might, on the other hand, use their own capacity to carry out studies on behalf of other countries. It is also planned to establish, within the framework of the project, pilot zones where field investigations and studies necessary for accomplish- ing specific tasks will be conducted. CONCLUSIONS The River Danube plays a vital part in the economic and social life of 70 million people living in eight different countries. The magnitude of the flow and also the quality of the water can have serious, and sometimes unforeseen, effects. With the rapid growth of population, industry, and agriculture in the catchment area, the river is subject to increasing envi- ronmental stress. If the river is to continue to satisfy all demands made upon it in the foreseeable future, it will be necessary to control and man- age the catchment as an entity. The first requirement is collection of data on the spatial and temporal variations in water quality and sediments through- out the system; the second is to reach agreement on the location and extent of the controls necessary at the least total cost to maintain the water in a condition suitable for all uses. There are difficulties in obtaining the 79 cooperation of upstream and downstream water users, both within as well as between countries, and the only feasible solutions are those based on uni- fied basin control within a country together with a strong cooperative or- ganization for international river basins. REFERENCES 1. Matrai, I. Canalization of the Danube and related water management problems. In: Proceedings of a WHO seminar on systems analysis in water quality management, February 1975, Budapest, Hungary 2. Benedek, P. et a l. Water quality and quantity aspects of the Hungarian part of the Danube. In: Proceedings of a WHO seminar on a systems analysis in water quality management, February 1975, Budapest, Hungary 3. Welev, D. Die Bedeutung der Donau fur die Bewasserung. Sonderheft Wasser - und Energiewirtschaft, Marz-April 1973, pp. 147-154 4. Fenz, R. Heutige und geplante Wasserkraftnutzung an der Donau. Son- derheft Wasser - und Energiewirtschaft, Marz-April 1973, pp. 100-114 5. International Atomic Energy Agency. The aim and role of IAEA's co- ordinated research programme concerning radiological safety on the Danube river. Report by the International Atomic Energy Agency to the UN-ECE Seminar on long-term planning of water management, Zlatni Piasa tzi, Bulgaria , May 1976 6. Report on a workshop on water quality of the Danube, Copenhagen, March 1976. Copenhagen, WHO Regional Office for Europe (document ICP/CEP 208) 7. United Nations Economic Commission for Europe, Committee on Water Prob- lems. Seminar on long-term planning of water management, Zlatni Pia- satzi, Bulgaria, May 1976 8. WHO Official Records, No.201, 1972 (Water quality in international water resources, resolution WHA25.43), p.20) 9. Leipolt, R. Uses of the Danube River, river ecology and man. New York, Academic Press, 1972 10. Research Institute for Water Resources Development (VITUKI), Budapest. Studies in the Danube region. In: Project terminal report, chapter 4 (document UNDP/WHO project HUN/PIP 001) 80 7. PLANNING REDUCTIONS IN THE EMISSION OF POLLUTANTS FROM INDUSTRIAL SOURCES R. Bouscaren 1 Since the end of the last century growth in industrial activity in many countries has led to distinct deterioration in air quality. Numerous at- tempts have been made through modern means of investigation to correlate the effects of air pollution with human health. It is generally ~ccepted that the effects of heavy air pollution are well established; on the other hand, the effects of chronic air pollution are less certain since there is often a very long latent period between exposure and detectable effects. In 1972, the Government of Spain asked the WHO Regional Office for Europe to inves- tigate, with UNDP funding, the serious and increasing problem of air pollu- tion in Bilbao and to make recommendations for its control. Similar acti- vities have been carried out elsewhere in Europe, but certain features of the Bilbao project have presented special difficulties. THE PRESENT SITUATION IN BILBAO Bilbao is characterized by a very large urban and industrial concentra- tion (more than 800 000 inhabitants) at the mouth of a deeply embanked river, the Nervion, running from south-east to north-west. The industrial activity of this area has existed since the beginning of the century and is very di- versified. The industry includes: - thermal power stations running on fuel-oil or coal, - iron and steel works (blast furnaces, steel works, coking plants, etc.), - a chemical industry (sulfuric acid, fertilizers, etc.), - foundries (iron and non-ferrous metals), - a petrol refinery (7 million tonnes/year output), - large ship-building yards and a port. The Bilbao region is developing rapidly; there is an expanding popula- tion and new industry, including iron and steel and petrochemical complexes. The population has become acutely aware of the air pollution problem and its effects on health, on agriculture, and on the environment generally and there is a general desire to improve the situation, without jeopardizing economic progress. 1 Formerly Senior WHO Technical Adviser. Present address: Centre interprofessionnel technique d'etudes de la pollution atmospherique (CITEPA), 76016 Paris. 81 The meteorology of the region is complicated because of the proximity of the sea and the presence of a deep valley and surrounding mountains. METHODOLOGY There is no simple and easy solution to air pollution in a seriously affected area, but certain steps can be taken to deal with the problem. They are: (1) to collect information about the nature of the pollution, (2) to collect information about the effects of the pollution, (3) to identify the sources of pollution, (4) to reduce and control polluting emissions, (5) to provide initial and refresher training for specialists in air pollution . The problem in Bilbao was too urgent to permit use of these procedures in a logical sequence, and they were therefore brought into operation together. Information about the nature of the pollution Measurements of ambient air pollution have been made over a 10-year period with the help of a small number of stations taking samples at 24-hour intervals (S02 by the "strong acidity" method and dusts by the Organisation for Economic Co-operation and Development (OECD) method of measuring the "index of blackness"). The information points were too far apart and unrep- resentative. For example, for S02 it was known that the pollution rate of 150µg/m 3 was exceeded on about 100 days a year, that the annual mean was of the order of 150 - 200 µg/m 3, and that on certain days the pollution exceeded 1000 µg/m 3. Furthermore, meteorological information was practically non- existent and also unrepresentative because it came from the meteorological station of the airport Sondica. The goodwill of the station personnel could not overcome the disadvantage of the airport being situated outside the val- ley of the Nervion. In 1974, the Corporacion administrativa del Gran Bilbao, which unites all the communes of the valley of the Nervion, with the technical and finan- cial assistance of the Free University of Madrid/IBM Research Centre, the Meteorological Institute, the Higher Council of Scientific Research, various ministries, and WHO, began to install a modern measurement network consisting of 8 automatic recorders for S02 , various gauges for meteorological data, and a system for the transmission of the data to a central post equipped with a computer. Measurement points for other pollutants are also being installed, e.g., measurement of the fluoride, sampling of the hydrocarbon complexes by the Junta de Energia Nuclear, apparatus provided by WHO for measuring the nitro- gen oxides, etc . Thus information about maximum concentrations and peaks 82 of pollution will become available. For example, for a number of years concentrations of S02 several times higher than 1000 µg/m 3 have been obser- ved and it will become possible to identify and control the sources of these emissions. Information on the effects of the pollution The Spanish health ser vi ces assisted by WHO experts are at present mak- ing an epidemiological study using s t andards for information treatment pro- posed in reports on visits to Spain by WHO consultants.l A first pilot study was made on 100 children in the region of Bilbao in order to test the methods used. The main study was carried out in May and June 1975 on 1000 children in each of four variously polluted sites in Greater Bilbao (Erandio, Portugalete, Guecho, and Plencia-Bilbao); this study was continued during the winter season of 1975/76 and the results are at present being processed. For this investigation, questionnaires were prepared, and measurements of the pulmonary ventilation of the children and measurements of the air quality made. Identification of the sources of poll ution Investigation and recording of emission sources was undertaken in 1974 by the Sub-Director General of the Industrial Environment and the Delegation of the Ministry of Industry in Bilbao with the help of WHO experts. It was found that more than 90% of the so2 emissions and dusts was due to the emis- sions from some 350 recorded industrial enterprises. Of these, about 50 have been made the subject of emission assessments, and it has been possible to select 46 installations where urgent action is necessary. As an example, the total emission of dust was estimated at 50 000 tonnes/year and the emission of so2 at 100 000 tonnes/year; one installa- tion alone emitted 15 000 tonnes of dusts per year and another emitted 50 000 tonnes of S02 per year. The calculation of a pollutant emission is, in itself, of secondary interest only; what is significant is the impact of this emission on the quality of the air at ground level: a heavy emission of S02 by a chimney 200 m high (therma l powe r s t a tion) may be l ess harmful than a weak emission at lower altitude, by a sulfuric acid plant, for exam- ple. This estimation of impact can theoretically be made with the aid of mathematical models for dispersion of pollutants in the atmosphere. Unfor- tunately, the complexity of the phenomena of atmospheric diffusion is so great that at present there is no model in existence capable of determining, within a reasonable margin of error, the risk of heavy pollution at ground 1 Van der Lende, R. Report on a visit to Spain, 1-10 May 1974. Copenhagen, WHO Regional Office for Europe (document SPAIN 3103, UNDP/SPA/ 73/003; van der Lende, R. et al. Report on a visit to Spain , 9-14 Septem- ber 1974. Copenhagen, WHO Regional Office for Europe (document SPAIN 3103, UNDP/SPA/73/003; van der Lende, R. & Peset Re i g , R. Report on a visit t o Spain, 17-22 November 1975. Copenhagen, WHO Regional Office for Europe (document SPA/CEP 003, UNDP/SPA/73/003). 83 level caused by a chi=ey. It has thus been necessary to estimate the relative impact of these emissions by using "commonsense" rather than a computer. Reduction in pollution emissions and controlling the reduction For the reduction of emissions of pollutants there are available a number of means that vary in the time taken to come into operation. These are as follows. (a) For the reduction of S02 pollution: (1) a change in fuel, either continuously or momentarily during "peaks" of pollution, provided that fuels with a low sulfur con- tent are available; (2) desulfuration of the combustion gases (installation of the equipment will take at least 2 years). (b) For the reduction of dust emissions better regulation of the com- bustion installations is necessary; priority should be given to intro- ducing this technique. When careful calculations to forecast emissions reductions are made, this simple means is surprisingly effective. On the other hand, use of the technique requires: (1) conscientious personnel with excellent professional training; (2) use of combustion additives (certain additives when properly used make it possible, among other things, to eliminate entirely the practice of sweeping); (3) proper maintenance of removal plant (it is not uncommon that for various reasons dust-removal installations do not function at all or function badly; regular inspection and maintenance are essential); (4) installation of dust-removal plant (this is an obvious remedy but is sometimes expensive and technically difficult); (5) modifications of operating procedure (in certain industries a change of this kind reduces the emission of dusts in a spectacu- lar manner; for example, in coking plants the proper burning of coke reduces by a factor of at least 10 the dust emissions at the time of discharging); (6) reduction in the rate of production (increase in the emission of pollutants takes place much more quickly than increase in pro- duction above the normal rate). It will be noted that most of the measures making possible a reduction in the emission of the two main pollutants (S02 and dusts) are relatively cheap and call for commonsense rather than innovation. On the other hand, it is necessary for specialists with extensive industrial experience to ex- amine the problems in detail and propose solutions. WHO and the Spanish administration therefore undertook three courses of action: 84 (1) dispatch of specialists in each branch of industry for well de- fined missions lasting from 8 days to 1 month in Bilbao; (2) increase in the personnel and equipment of the control services of the Spanish administration; (3) provision of professional training courses in Madrid with the assistance of advisers of internat ional reputation. Specialized consultants from industry who have, or who have had recent- ly, responsibilities in the fields of environment and production and are familiar with both techniques of prevention and measurement and of the tech- nical constraints in industrial production, have been selected by WHO, while the Spanish authorities have laid down plans for reducing air pollution in stages. In order to facilitate the application of these measures, the Ministry of Industry has drawn up and published a number of legislative acts, and in 1975 a very comprehensive decree stipulated, among other things, emission standards according to type of industry and air quality standards for the main pollutants. Initial and refresher training of specialists In resolving the different interests of state and industry, it is essen- tial that well trained professionals should be available on both sides. Their training should, as far as possible, cover both industrial and conser- vation aspects in order that each side understands the other 's point of view. In the same way, refresher training of specialists facilitates recruitment of competent personnel needed by the administration and the industry respon- sible for the industrial environment . In Bilbao a first training course dealt in general with the problem of air pollution, a second with epidemiological studies , and a third , more specialized, with the measurement of pollutants coming from industrial sources . The teachers were in all cases specialists of international repu- tation and open discussions (general or particular) enabled participants to present, or to have explained to them, problems of particular concern . WHO fellowships have also been proposed for engineers, physicians, biologists, etc., to acquaint themselves with, and practise, various techniques used in foreign countries (USA, France, Netherlands, United Kingdom). CONCLUSIONS Problems encountered in Bilbao, the pilot site for an air pollution control project, are those likely to be met in protecting the environment in any industrialized country. The difficulties are perhaps more numerous than elsewhere owing to the intensity of the pollution and the long history of the problem. Solutions are being introduced in steps, an organization is being built up, regulations have been brought into force, and means have been provided to carry out studies and measurements of the air pollution. 85 Experience gained in Bilbao could be used effectively not only in other polluted areas in Spain, but also in other industrialized countries. The procedures followed in the Bilbao area are not necessarily suitable for direct application elsewhere; modification and adaptation to meet local conditions and needs will probably be necessary. Future records of ambient air pollution and epidemiological surveys will indicate how much has been achieved by this project. In any case, the establishment of collaboration between a ministry for industry, a health service, industry, and an international organization represents a major ad- vance in tackling the problem of environmental pollution. 86 8. COMMUNITY NOISE STUDY IN THE ATHENS METROPOLITAN AREA -- J.S. Simandonis1 Noise pollution control forms an integral part of a comprehensive en- vironmental pollution control project in the Athens metropolitan area. This is a collaborative venture of the Greek Government, the United Nations Development Programme (UNDP), and the World Health Organization acting as the executing agency on behalf of UNDP . A common impression of the situation in Athens is that noise levels from traffic are higher than in other European cities, due mainly to a high proportion of inadequate exhaust mufflers on motor vehicles, excessive use of low gear, and frequent use of the car horns. Construction noise is also prevalent at present in the metropolitan area. It was decided to perform a large-scale noise survey within the Athens metro- politan area to determine the effects of exposure to environmental noise on the population. The area where aircraft noise is predominant was in- cluded in the survey but, because of its importance, this problem has been studied, and will be reported, separately. The study was divided into two parts. The first concerned objective noise measurements for assessment of environmental noise in representative sites. The second part consisted of a social survey, employing a question- naire, intended to ascertain if noise is considered a problem by the inhabi- tants of Athens and, if so, what the main sources of public annoyance are. A further purpose of the social survey was to relate the reported degree of annoyance to ambient noise levels in order to establish a dose/response re- lationship as a basis for development of national noise criteria and stan- dards. PLANNING AND EXECUTION OF THE INVESTIGATION Selection of investigation areas and measurement points Various parts of Athens were selected as representative of the different types of area that make up an urban community. In order to avoid biased selection of measuring points a grid sampling method was used, noise meas- urement points being determined by chance. A grid consisting of a series of parallel lines the equivalent of 500 m apart was superimposed over a map of the area under investigation and the noise measurements were conducted at the nearest approachable location to each grid point. 1 Senior Noise Control Officer, Environmental Pollution Control Project, Athens, Greece . 87 Similar systems have been applied in earlier studies in London (1), and in the USA in Philadelphia (2) and Medford, MA (3). Short des criptions of t he areas and the total number of measuring locations within each area are given in Table 1. Table 1 AREAS WHERE NOISE MEASUREMENTS WERE TAKEN AND NUMBER OF NOISE MEASUREMENTS CARRIED OUT IN EACH AREA Type of area Central area Residential I: typical residential area with main roads and shopping centres Residential II: fringe residential area, with main roads and some indus- trial activities Suburban I: mainly detached houses, close to the centre, no main roads, little traffic Suburban II: typical suburban area far from centre, with some main roads but little traffic Industrial I: mostly open, rural area with some dispersed industrial units Total Noise measurements No. of measuring points 36 42 15 25 25 36 179 Environmental noise in each site was recorded on portable tape-recorders for 1 hour cont inuously between 08 00 and 13 00 on weekdays. This period of the day was selected because traffic flow is then steady, neither maximum nor minimum. The difference in noise level between the time of day when a noise measurement was made and any other time can be determined with some accuracy with the aid of 24-hour noise measurements graphs showing the pat- tern of daily fluctuations in noise levels. The 24-hour recordings were made in a number of locations in each area under investigation. The noise was recorded on tape for about 8 seconds per minute over the period. In 88 the laboratory, noise (LEQ• Li, mined for each site by means of computer programme. Noise exposure 1 Lio, Lso, L90 and LNP) levels were deter- a statistical distribution analyser and a The results of the noise measurements for the different areas under in- vestigation are illustrated in Fig. 1 and 2 . These graphs show the propor- tion of measuring sites within each area where a given noise level or greater is found (indicated in the abscissa); they thus offer a good rep~esentation of the existing noise situation in each area. As expected, the central area proved to have the highest range of noise level probabilities with LEQ ranging from 61 dB(A) to 77 dB(A) and a 50% probability of 73 dB(A). The two densely populated re s idential areas showed a range 3 - 5 dB(A) lower than that in the central area. In the residential I area LEQ ranges from 53 to 77 dB(A) and the 50% probability is 67 dB(A). In the residential II area LEQ ranges from 58 to 74 dB(A) wit~ a 50% prob- ability of 70 dB(A). The suburban areas are, as expected, less noisy. The suburban I area, closer to the central area, has a range of LEQ from 53 to 67 dB(A) except at one point located on a main avenue, and a 50% prob- ability of 62 dB(A). The suburban II area, the outermost, is also the quietest, having an LEQ range from 51 to 72 dB(A) and a 50% probability of 59 dB(A). As far as the 24-hour noise measurements are concerned, typical daily noise fluctuation in two sites located in the central and residential I areas is presented in Fig. 3 and 4. For the central and residential areas there is a surprisingly low variation in noise levels during the 24-hour period. The night-time period is very short and most activities such as working, relaxing, and even sleeping, are carried out under similar noise levels. 1 LEQ (energy equivalent nois e level) is an index used when the noise level varies with time, as in the case of traffic noise. This is the level of steady noise that has the same amount of energy as the varying noise under consideration. that L95 L % (or L) is a series of noise indices that refer to the noise level i~ 0 exceed~d for a certain percentage (x) of the time. Usually, L1 and are used to indicate the peak and background noise levels, respectively. LNP (noise pollution level) is a community noise index that takes into account, in addition to the noise level itself (in terms of LEQ), also the magnitude of its variation. 89 Fig. l 100 90 80 70 60 ~ ~ ;,-. w ..... ...... 50 ..... .n "' .n 0 ~ p.. 40 30 20 10 0 50 l CUMULATIVE SPATIAL DISTRIBUTION OF NOISE LEVEL (LEQ) FOR THE ATHENS AREA ', ·,, \ \ I I \ \ I I ' I ' ' I I i I \ ------- Central \ I I \ - ·- ·- ·- ·-·- Resident ial I - ··-··-··-··- Industrial I - ··· - ···-· ··- Suburban I \ Residentia l 11 Suburban II 55 60 Cf) 65 Noise level (dB(A)) 70 75 1 For a definition of this term, see footnote on p. 89. 90 80 Fig. 2 100 90 80 70 60 ~ ~ ._., ;,--. '-' ..... "" ..... 50 .D <11 .D 0 .... p.. 40 30 20 10 0 CUMULATIVE SPATIAL DISTRIBUTION OF PEAK NOISE LEVEL (11) 1 FOR THE ATHENS AREA \ \ \ \ \ \ \ \ \ \ \ \ \ \ .... '· ......... \ I \ '<fl \,. I \ I \ I ·, ... I I \ \ --------- Central - ·-·-·-·- Residential I -··-··-··- Industrial I -·· ·- ··· - Suburban I ·---·---· Residential II ·--·--·-- Suburban II 60 65 70 75 80 85 Noise level (dB(A)) 1 For a definition of this tenn, see footnote on p. 89. 91 90 \0 N Fig_. 3 110 100 90 ,5 80 °" :'.: ..... OJ ;, OJ ...., 70 OJ "' ..... 0 z 60 50 40 6 24-HOUR NOISE LEVEL1 FLUCTUATION IN A TYPICAL CENTRAL LOCATION .... __ _ -- --- ,----........ -- ------ .... - -- ,, , ,, ..... __ --- .... .,," __ , , , , ," , ' ,,, ' , _______ ,,, ---- 150 -- _ .... ______ _ _ ------- ----- -===-:-, -- -- --- ,, -- , _,,,-,=----- L - ',', , ' ,' , ,;== =o_ -:_~--:_-_-_ _ ,, -- - ---:_-:_=== = s, 90 , ~- , , -- -- -_- -- ', ,' ,',' ,', - -~----,- --- -,;,_ ',_ --- ,, /,' ',/L95 ','.c,, --- ',' ,, . , ,,,, .. ,,, , / ,, ,' ,, , , _______ __ _ ______ .,,,,. 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 1 2 3 4 5 Hour of day 6 1 For definitions of the various noise indices, see footnote on p. 89. \0 w Fi_g_. 4 110 100 90 ~ 3 "' .,,, ~ 80 .-i QJ > QJ .-i QJ "' ..... 70 0 z 60 so 40 6 24-HOUR NOISE LEVEL1 FLUCTUATION IN A TYPICAL RESIDENTIAL LOCATION -------- ,,,----- ,, .... .,,..,' ...... , ------ 1 50 ---- ,____ ----------- ................ ____ .... , / ......... / , , , ------------ ......... , .... __________ ,, ,,,,' , I I ----, '---,, , I' ,-:c,._ ½o ___ :--=-== =----_-_-_- _ - ---o-,, ' - , ,' ,>' - --·-- - -:-- '=:--- - - - - - - --- , ,, -- ,',----,----,, L95 ',=:-, ,____ , / --= -:.---a- '• ___ , ,,- -- ,, __ ,,;, ',-:.-:_-:::::::.:-:, __ _ ,, 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 1 2 3 4 5 6 Hours of day 1 For definitions of the various noise indices, see footnote on p.89. Industrial noise The so-called industrial I area is a mixture of light industrial and commercial units interspersed with numerous individual residences. The main noise sources within this area were found to be traffic and workshops. In the other areas traffic was by far the most important source of noise. Construction activities are also important sources of local noise. Traffic and noise An attempt was made to fi nd a correlation between traffic volume and noise in the city of Athens. Since the main source of community noise was found to be traffic such a relationship could be used in predicting the noise situation at a specific site by counting the number of vehicles passing. This prediction technique could be used in rerouting traffic in order t o provide relief for unacceptably noisy residential areas. It is very difficult to establish a single formu la for genera l us e since a wide range of factors affect the noise level produced by traffic. Some of the most important factors are: (1) percentage of motorcycles and heavy vehicles in the traffic flow, (2) average speed of vehicles, (3) inclination of the road surface (up or down hill), (4) types of structure, or absence of structures, along the sides of roads, (5) presence or absence of traffic lights, (6) aggressiveness in driving, (7) levels of car and road maintenance. In spite of the difficulties, an attempt was made to derive a formula, and this was found to be in fairly good agreement with similar attempts made in Austria for the cities of Vienna and Gratz. The attempted correlation between traffic volume and noise level (4:q) for the city of Athens is presented in Fig. 5. This figure is based on noise measurements and simultaneous traffic volume figures at 55 points taken from both the central and the residential I areas. The correlation can be expressed by the formula LEQ = 54 + 6.4 log10TV, with a standard deviation of r = 2 .75, where LEQ = energy equivalent noise level (dB(A)) and TV= traffic volume (vehicles per hour). 94 '° V, Fi_g_. 5 100 90 80 3 70 0:, ~ ,...; (1J > (1J 60 ,...; (1J U) .... 0 z 50 40 3- D D D NOISE LEVEL (LEQ)l PLOTTED AGAINST TRAFFIC VOLUME IN THE ATHENS METROPOLITAN AREA 0 6 0 t:,. 0 0 t:,. t:. t:,. 0 0 □ motorcycles+ heavy vehicles > 30% 'IP O 15% <motorcycles+ heavy vehicles < 30% 6. motorcycles+ heavy vehicles > 15% Logarithms of traffic volume figures 1.2 1.3 1.4 1.5 1.6. 1. 7 1.8 1.9 2.0 2 . 1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 3.0 3 .1 3.2 3.3 3.4 3.5 3 .6 3 . 7 25 50 100 200 500 1000 2000 4000 Traffic volume 1 For a definition of this term, see footn ote on p. 89. Social survey Questionnaire. The 4-part questionnaire was based on those used in similar investigations in the United Kingdom (4, 5) and the USA (2), but modified to meet local conditions and customs. Part 1 covered biographical data and included questions about name, date of birth, education level, type of em- ployment, and length of residence in that neighbourhood and in Athens. Part 2 attempted to determine the subject's general attitude to his living environment before he became aware of the special interest of the survey in noise. The subject was also asked to give "free" responses concerning what he liked and what annoyed him in his own area . In the last question of part 2 of the questionnaire the subject was asked to rate his degree of an- noyance with various types of urban problem, including noise. Part 3 revealed to the subject by its content, that the survey dealt with noise. He was asked to rate overall noise in his environment according to a 1 - 9 scale and then to answer specific questions concerning his reactions to different types of noise, times of annoyance, activities disturbed by noise, and his occupational noise experience. Finally, the subject was asked to express his opinion about the types of action that should be taken to control noise in the city. Part 4 established the physical conditions under which the subject lived by type, position, and size of residence, and number of persons living there. Selection of subjects for interview. The sampling process comprised two stages: initially, a list was prepared including names, ages, sex, and lo- cation of household of all of the inhabitants around each of 60 selected points in both central and residential I areas where 1-hour noise measure- ments had already been made. This inventory totalled approximately 6000 households and 20 000 inhabitants over the age of 16. Once the list was prepared the second stage was implemented - namely, selection of a repre- sentative cross-section of the listed names according to location and floor of residence, age-group and sex. From the 20 000 individuals on the list, a sample of 2400 was finally chosen for individual interview; of these, 1889 were located and interviewed, the response rate being 78.8%. The social survey was made possible by the cooperation of student nurses from the School for Visiting Nurses of the Ministry of Social Services, who are trained in interview techniques. It was emphasized to interviewers that the subjects were not to know the exact objective of the survey prior to interview and that while every effort should be made to obtain a complete response from each subject, the interviewer should avoid any attempt to influence the subject's response. ANNOYANCE REACTION Some preliminary results of the noise social survey are reported below. In a first phase of analysis a breakdown of results of answers for each question was determined . Table 2 gives some important social background data for the interviewed population. 96 Table 2 CHARACTERISTICS OF SUBJECTS INTERVIEWED Sex distribution (%) Educational status (%) male, 44 university, 13 female, 56 high school, 30 grammar school, 42 grammar school, not completed , 8 illiterate , 4 Age distribution (%) Length of residence in area (%) 16 - 29 years , 21 0 - 2 year s , 20 30 - 59 years, 56 2 - 5 years , 23 60 years and over 5 years, 48 over 21 Results from the evaluation of the spontaneous rating of different environmental annoyance sources demonstrate that noise itself and noise- related disturbances were by far the most important annoyances reported ; 40% of the respondents spontaneously mentioned noise and below this, 27% mentioned air pollution. It can be seen from the following tabulation that air pollution and noise are the most important of the various environmental annoyances in Athens. Environmental factor air pollution noise pollution traffic litter parking facilities, lack of Respondents "much" annoyed (%) 78 78 71 43 36 When the respondents were asked to name the noise sources they thought were important, the most significant answers were "traffic" (44%), "motor- cyles" (15%), and "trains" (6%). When the respondents were given a list 97 of noise sources and asked how much they were annoyed by each of them, the highest significant weights were again given to traffic and motorcycles , but some other noise sources also proved to be annoying, as shown in the fo llowing tabulation. Noise source motorcycles traffic compressors trucks car horns construction work industries Respondents "much" annoyed (%) 51 44 24 24 21 18 6 Interfer ence with sleeping , e ither in the afternoon or at nigh t, and interference with relaxation wer e reported by the larges t proportion of re- spondents. Relatively little interference was reported for watching t e l e- vision and fo r conversation, as shown below . Activity sleeping - afternoon - night relaxing reading and studying working watching t e levision conversation eating enter tainment Respondents "often" disturb ed (%) 34 30 34 15 8 7 7 6 4 According to the answers given, it is clear that 80% of the population feel that noise affects their health and 17% of the sample us ed sleeping pills or tranquilizers. This last fact may prove to be significant if that 17% is shown to be exposed to significantly higher noise l evels than th e rest of the sample population. Finally, 40% of the sample felt that there was nothing that could be done to help ameliorate the noise situation. Of 98 those that felt there was something that could be done for relief, 40% ex- pected the solution to lie in new legislation while an additional 30% felt it would depend on some other government-initiated action. RELATION BETWEEN ANNOYANCE AND NOISE EXPOSURE One of the main aims of the noise study in Athens was to establish a relationship between annoyance experienced and the noise level producing it. Firstly, an attempt was made to correlate noise annoyance averages in each location (taken from answers to the questionnaire) to the measured noise levels for each site; initially, correlation was very low. It was then found that while the noise measurements were made at only one spot in each location, the interviews with respondents covered two or three blocks around the measurement spot. It is highly probable that many respondents were exposed to noise levels substantially different from those measured. To correct this defect, in each area respondents were selected who had addresses in the street where the nois e measurement was made . Of the 1889 re- spondents, 495 were found to fit thi s r equir ement. Of these, there were 10 or more in each of 22 areas out of the 60 in which the social survey was conducted. When the weighted average annoyance for each of these 22 areas was plot ted against their respective noise measurements, expressed in LEO (Fig. 6), a good correlation was then found (r = 0.63). The weighted average annoyance for every area was derived from the question, "how much are you annoyed by noise in your neighbourhood?" and weights assigned to the answers were 1 for "not at all", 2 for "little", and 3 for "much". One more attempt was made to relate annoyance and noise exposure. In each of the 22 areas mentioned above the percentage of respondents highly annoyed, derived from the same question as above, was plotted against the noise levels to which these people are exposed , using intervals of 5 dB(A) (Fig. 7). The correlation coefficient was found to be very high (r = 0.9). DISCUSSION Noise situation As Fig. 1 and 2 show, in comparison with national and international (6) noise criteria large parts of the areas selected as representative of the Athens metropolitan area are exposed to high levels of environmental noise. According to the criteria adopted by the United States Department of Housing and Urban Development (7), the whole of the central area is considered as normally or clearly unacceptable. If the area were reserved for commercial purposes this might not be so important, but since there are large numbers of residents and many major hotels, the noise problem becomes significant. When the residential areas are examined, 75% of the measured locations fall in the "normally" or "clearly unacceptable" categories. This indicates 99 Fig. 6 Much QJ () i::: ell >-. 0 i::: Little i::: ell .... 0 QJ QJ H bO QJ ~ Not at all WEIGHTED AVERAGE ANNOYANCE AS A FUNCTION OF THE EQUIVALENT ENERGY NOISE LEVEL (LEQ)l 3 2 1 50 60 70 80 Noise level (dB(A)) 1 For a definition of this term, see footnote on p. 89. 100 ,-.. ~ ....... "Cl Q) >, 0 i:: i:: Cll >, ,-i ..c: bl) . .., t= CJ) -1-1 i:: Q) "Cl i:: 0 p.. CJ) Q) P::: Fig. 7 80 60 40 20 0 50 PERCENTAGE OF RESPONDENTS "HIGHLY ANNOYED" AS A FUNCTION OF EQUIVALENT ENERGY NOISE LEVEL (LEQ) l 55 60 65 70 75 Nois e l evel (dB(A)) 1 For a definition of this term, see footnote on p. 89. 101 80 a major area problem since the population resides in build ings without any special noise insulation and, furthermore, windows remain open during most of the year. In the suburban areas, 37% of measured locations are classi- fied as "normally unacceptable", although these areas are considered as quiet by most Athenians. This view, despite the fact that no area of Athens meas- ured to date can be classified as "clearly acceptable", indicates the dif- ference in noise levels. Sensitivity to noise differs greatly between Greece and the USA, and probably many European countries, also; it is therefore important to study local people's reaction to noise. Social investigation As mentioned above, analysis of the data collected by the social survey is continuing and a full report on the results will be presented later. Two points only are discussed here. The activity disturbance pattern found in this investigation, where traffic noise was predominant, is different from that caused by aircraft noise. The most important activity disturbance reported for traffic noise was related to sleep and relaxation while interference with conversation and televis ion-watching ranks relatively low. The contrary is reported for ac- tivity interference due to aircraft noise (8). High levels of annoyance due to construction noise were reported for certain areas . Previous investigations have shown that noise from construc- tion equipment constitutes an important part of the environmental noise con- sidered to be annoying by the exposed population (9) . This has led, among other things, to the development of compressors with a substantially reduced noise output. Such types of compressor are available in Athens but are often stripped of their noise insulation in order to reduce cost. This indicates the need for adequate legislative measures and enforcement if the noise pol- lution of Athens is to be controlled. ACKNOWLEDGEMENTS The author gratefully acknowledges the help of Dr J. Lang, WHO consul- tant, who suggested the basic ideas for this investigation and contributed greatly to its initiation. Thanks are due also to Professor J.B. Large and Professor R. Rylander for their assistance in the presentation of this report. 102 1. 2 . 3. 4. REFERENCES Parkin, P.H. et al. London noise survey. tionery Office, 1968 London, Her Majesty's Sta- Bragdon, C.R. Noise pollution - the unquiet crisis. University of Pennsylvania Press, 1970 Philadelphia, Wesler, J.E. Community noise survey of Medford, Massachussets. Journal of the Acoustical Society of America, 54:4 (1973) McKennell, A.C. Noise - final report 1963. Stationery Office, 1964 London, Her Majesty's 5 . McKennell, A.C. & Hunt, E.A. Noise annoyance in cent ral London. 6. 7. London, Building Research Station, 1966 Basternier, H. et al. Damage and annoyance caused by noise. sion of the European Communities (document EUR 5398e/1975) Commis- Beranek, L . L. 1971 Noise and vibration control. New York, McGraw-Hill, 8. MIL Research Limited. Second survey of aircraft noise annoyance around London (Heathrow) Airport. London, Her Majesty's Stationery Office, 1971 9 . Large, J.B. & Ludlow, J.E. Internoise 75 Community reaction to construction noise. 103 9. FOOD CONTROL 1 2 B. Blomberg & A. Wahba Food safety is essential for the promotion of community public health, and all efforts leading to its achievement will help prevent the spread of many communicable and noncommunicable diseases. Food safety problems in the past were both different and much less complex than they are today. Until quite recently, food production was principally a local industry, and there were many limiting factors . The pattern of living supported a system where food was produced by those who consumed it or by their immediate neighbours. The families, or at least villages, were to a great extent self-sufficient units and society as a whole was fairly stable with only limited migration. This was true in Europe up to about a hundred years ago. Then began a new phase with rapidly increasing industrialization and urbanization and a tremendous growth in world production of, and trade in, foodstuffs, with a parallel increase in the risks of contamination by chemical and biological agents. This applies also to animal feeds, and once a portion of the food ch~in becomes contaminated human health may be endangered. Several factors contributed to a change in eating habits. Awareness and knowledge of the importance of good nutrition increased, and with rising standards of living it was possible to buy more meat, more fruit, and more fresh food to replace salted food. New methods were applied, both for the production and the processing of food. However, domestic cooking habits have proved to be very stable and most people are conservative in their eating habits, tending to cook and eat like the previous generation. For example, conservation of vitamins in food through moderate cooking has taken much time to learn. The revolution in food processing came with the introduction of chemi- cal additives to increase the shelf-life of food, improve its taste, and to change its texture or colour. This has had both good and bad effects. Preservatives are necessary in the mass production of many kinds of food . 1 Technical Officer for Food Safety Programme, WHO Regional Office for Europe, Copenhagen. 2 Regional Officer for Public Health Laboratory Services, WHO Regional Office for Europe, Copenhagen. 104 Today, a foodstuff passes through many steps from production to consump- tion - storage, transport, processing, distribution, packaging , sale - t aking more time than before. Preservatives help to keep the foodstuff in good condition throughout this chain and help to increase the selection of fo ods available to the consumer. However, certain preservatives such as nitra tes and nitrites can lead to the production of toxic substances, e.g., nitro- samines that have been implicated in cancer etiology. Other chemical substances are added to reinforce the natural taste of a food or to add a new flavour. This may contribute to an increase in the amount of food available globally by making possible the consumption of foods made from unconventional raw materials such as algae. Chemical food additives are also used to change the organoleptic prop- erties. Use of this group of additives has been widely criticized, but experience shows that it is not easy to change established consumer habits and certain colours are associated with certain foods. If use of chemical colouring agents were only a matter of making food look attractive the question would not be very serious, but there are other aspects. Colours, flavours, etc. , may be used to give the impression that the quality of the food is higher than it in fact is. What is more serious is that some additives may have toxic effects. With increasing use of additives, health risks also increase. Studies on food additives are continually being advanced, and FAO and WHO jointly have regularly convened expert committees on food additives since 1955. However, new chemical additives are placed on the market all the time. The toxic effects of these substances and their different inter- actions are carefully investigated, and most countries have strict regula- tions about what may be added to foodstuffs. Some countries apply the "positive list" system, meaning that only those additives listed are per- mitted, all others being prohibited. A few countries have a "negative list" system, while several countries have a system that combines both principles. The reason for a mixed system is that it is easy to list some substances that should be prohibited, but in other cases, flavourings for example, it is not yet feasible to make positive lists. Some foreign substances in our food arrive there unintentionally - pesticide residues, residues of antibiotics or anabolic agents used in animal feedstuffs, traces of fertilizer, and other environmental contami- nants such as pathogenic micro-organisms and mycotoxins, 1 heavy metals, and polychlorinated biphenyls. Of all the different routes by which harm- ful substances in the environment reach man, food is one of the most impor- tant. Joint FAO/WHO expert committees meet regularly to evaluate health hazards connected with pesticide residues and other food contaminants. 1 i.e., toxic substances of fungal origin. 105 These committees establish tolerance levels for various substances and revise those levels in the light of new research . If the addition of chemical substances to food caused the first revolu- tion in the food field, the second revolution came with mass catering. Many people eat at least one meal a day in restaurants or canteens where they work, schoolchildren are given a meal at school, and old people often have a home delivery of a pre-cooked meal. In addition, there is the great increase in international travel of all kinds, mainly tourism. The possibilities of widespread ill effects from seriously contaminated food are thus much greater than previously. Special consideration must be given to baby foods and geriatric foods on account of the special suscepti- bility of infants and old people to health hazards. Also, nonconventional foods, prepared from new raw materials, may present problems and must be carefully tested for safety and nutritional value. Rising standards of living provide the economic possibilities to buy good food, and new techniques, especially deep-freezing, have opened up new possibilities for varying the diet with imports of fruits and vegetables from other countries and for eliminating seasonal food shortages. Increased knowledge and interest in nutrition allow the more imaginative planning of menus. But, higher living standards have their negative sides as well. Large-scale serving of food multiplies health risks from contaminated food and much more consideration .must be given to personnel hygiene and to proper food handling procedures, both before and after cooking and while the food is kept warm or is stored for later use. In this connexion, one special risk area is aviation catering . In general, national rules of hygiene, food handling, cooking, etc., are very strict and apply to all forms of collective feeding but problems arise in their application. Control and supervision must be improved; for tnis, good advice and information are essential. More packaged foods are now being sold in supermarkets where the r.on- sumer often has no means of judging the quality, and new types of food appear frequently on the market. Consumers are therefore demanding more information about food and about health risks associated with food additives and food contaminants. In many countries with high living standards, overeating may be a serious problem, leading to a type of malnutrition. Daily work may not be as strenuous as before and many people get too little physical exercise, and thus need less food. There is often too much sugar and fat in the diet, providing energy but too little protein, iron, and other essential nutrients. Certain socially active groups often call for the banning of chemical additives including colours and flavours in foods as part of a general trend towards a simpler life style. The counter-argument is that this is im- possible; owing to methods of production, market demands, and transportation problems, the presence of chemicals in food must be accepted. However, the problem of food safety in relation to public health is of great concern 106 to governments in all countries and there is a possibility that countries will use protection of its population against food-borne heal th risks as a reason for establishing trade barriers. This would be unfortunat e and unnecessary. In 1963, a joint FAO/WHO progrannne on food standards was established, with the FAO/WHO Codex Alimentarius Commission as its principal organ. Protection of the health of consumers is the primary aim of the Commission. The work of the Codex Alimentarius Commission is supported by several joint FAO/WHO expert committees that meet regularly to provide the scientific basis for health aspects of Codex standards. Thus, there are connnittees on food additives, pesticide residues, food hygiene, and irradiated foods. Various meetings have been held on problems of nutrition. During the last years special attention has been paid to microbiological hazards, and experts have met to discuss possibilities of setting microbiological speci- fications for certain foods. Foods requiring such specifications are those that are implicated repeatedly in outbreaks of food-borne disease or that contain disease-causing micro-organisms which could, as a consequence of mishandling, create a health hazard. Whereas food safety evaluation - establishment of food standards, acceptable intake levels, etc. - is mainly the responsibility of WHO head- quarters, the work of the WHO Regional Office for Europe in the field of food safety concentrates on food control, with emphasis on preventive and advisory aspects. The reason for this is that, although most countries in Europe seem to have adequate food legislation and rules for food control administration, the practical application of the rules and the implementation of controls still need to be improved . The main problem areas have been identified as mass catering and food information. Since outbreaks of food-borne diseases originating from aviation catering are a matter for some concern, a working group was convened by the Regional Office in 19761 to discuss problems that, because of lack of storage space and refrigeration facilities, are particular to this type of catering. Studies and working groups on other aspects of mass catering are planned, for example, catering in other forms of travel, hospital catering, and heal th hazards associated with vending machines. A survey of food control administration in Europe is planned, and this will be followed by a meeting to discuss the flow of information between authorities, industry, and consumers. 1 A . . . v1at1on catering, November - December 1976. 1977. Report on a Working Group in Torremolinos, Copenhagen, WHO Regional Office for Europe, 107 L A conference on food control labora tories is being organized by the Regional Office for Europe in October 1977, to review and appraise the organization of food control laboratories at the central, regional, and local levels and the methodology of food control. Several WHO-supported international courses in food microbiology are arranged each year in Europe, and the organization of an international course in food microchemistry has also been proposed. Conclusions In the field of food safety it is necessary to try to develop a balanced approach, to find methods of improving transport and storage of foodstuffs, and to use chemical substances or other processes in such a way that they help to improve the quality of the food without causing health risks. Continuous surveillance of food hygiene, especially in connexion with mass catering, training of personnel, and dissemination of information to all persons involved in food processing, handling, and sale and also to the public are essential activities in keeping the number of cases of food- borne disease as small as possible . SELECTED READING Codex Alimentarius Procedural Manual, 4th ed., Rome, Food and Agriculture Organization, 1975 Food hygiene, Report on a Seminar in Warsaw, August 1970. Regional Office for Europe (document EURO 0389) Copenhagen, WHO Guidelines for developing an effective rational food control system, prepared in collaboration with the United Nations Environment Programme. Rome, Food and Agriculture Organization, 1976 Microbiological specifications for foods, Report of a Joint FAO/WHO Expert Consultation. Rome, Food and Agriculture Organization, 1975 Prevention of inter-country spread of infectious diseases, Report on a Con- ference in Izmir, June 1974 . Copenhagen, WHO Regional Office for Europe (document EURO 1002) Public health aspects of antibiotics in feeds tuffs, Report on a Working Group on Control of Harmful Residues in Food for Human and Animal Consump- tion, Bremen, 1973. Copenhagen, WHO Regional Office for Europe, 1974 (document EURO 3604(2)) 108 WHO Food Additives Series. Geneva, World Health Organization (for a list of titles see Catalogue of World Health Organization Publications and Supplement to Catalogue) WHO Pesticide Residues Series. Geneva, World Health Organization ( for a list of titles see Catalogue of World Health Organization Publications and Supplement to Catalogue) 109 Summary 10. TOURISM AND SANITATION IN EUROPE E. Giroult1 The countries of Europe have largely overcome environmental health prob- lems connected with microbiological contamination by parasites, bac t e ria , and viruses; however, the occurrence of minor epidemics of infectious dis- eases from time to time shows that there are still many shortcomings, espec- ially in Mediterranean countries, where the relatively hot climate favours the spread of pathogenic organisms . Local inadequacies become a more gen- eral problem when they affect areas or districts visited by tourists from other countries. A major cause of difficulty lies in the seasonal nature of tourism and in the great disparity in the size of the local population and that of the total population during the holiday season. The WHO Regional Office for Europe is giving serious attention to health aspects of tourism and is concerned with improvement of sanitation conditions for tourists throughout the r egion by e ncouraging coope r a tion among Membe r States and fostering a better understanding of the problem. Only environ- mental aspects are considered here. INVENTORY OF SHORTCOMINGS A number of environmental health shortcomings in tourist areas may affect the health and wellbeing of holiday-makers and local populations a like. The main shortcomings include: (1) lack of adequate supplies of fresh water; (2) unsatisfactory bacteriological quality of drinking-water or of foodstuffs; (3) poor chemical quality of drinking-water and food; (4) inadequate hygiene of tourist accommodation with regard to clean- liness, disposal of liquid and solid wastes, and sanitary facilities; 1 Regional Officer for Basic Environmental Services, WHO Regional Office for Europe, Copenhagen . 110 (5) inadequate hygiene of tourist accommodation with regard to venti- lation, lighting, air-conditioning, living-space , and so~nd insulation; (6) inadequate hygiene of tourist accommodation and restaurants with regard to control of insects and rodents; (7) inadequate hygiene of places of recreation (e.g., bathing beaches and pools and also indoor recreational facilities including clubs and bars); (8) insufficient protection of the public against accidents in the above-mentioned places of recreation and on traffic routes. Tourism results in the temporary transfer of large numbers of people to a new environment where they may encounter micro-organisms to which they have no immunity, but against which the local population has acquired resis- tance. The need for strict hygienic measures to protect vulnerable visitors is th_erefore particularly important in tourist areas. CAUSES OF SHORTCOMINGS (a) The primary responsibility for environmental health activities in most countries of the WHO European Region rests with the municipal authori- ties. The municipalities are organized to serve resident populations but during the tourist season these populations are augmented both by a large number of seasonal workers from neighbouring areas and by tourists from home and abroad. Certain seaside resorts thus find their population increasing five-fold during the summer season. (b) If the services for water supply, refuse collection, and sewage disposal are organized for peak population numbers, the fact that they are under-utilized for a large part of the year gives rise to financial and tech- nical difficulties. Geographical location and climatic conditions also add to the problem. For example, older resorts in mountain areas were located in the valleys but modern winter sports centres are built at high altitudes in the mountain pasture zone. As these centres are occupied throughout the winter the mu- nicipal sanitation services have to contend with both topographical and cli- matic difficulties. Similarly, on the coast tourist buildings are construc- ted on land that is not always well suited to human habitation. Here, more- over, the tourist season corresponds with the hottest time of year, when the spread of pathogenic organisms is most rapid. Also, the end of summer co- incides with the lowest water levels in aqueducts and surface impoundments. (c) The smooth functioning of municipal sanitation ser~ices requires a permanent staff of competent technicians and engineers; it is generally recognized that a municipality of 15 000 inhabitans should employ a sanitary engineer on a full-time basis. Small resorts situated in close proximity can, if necessary, group together so that joint sanitation services are 111 feasible. The municipal services of small towns need the t echni cal support provided by a national administration; this may take the f orm of a sanitary engineering service of the ministry of health, for example . Clearly, such a service should exist and be correctly structured. (d) Differences in customs, culture, cuisine, language, and admini- strative practices between the countries sending and receiving tourists also give rise to difficulties . Eating habits have a direct relation to intes- tinal disorders . (e) Another difficulty is linked with commercial pressures and the im- balance between supply and demand, leading to the acceptance of more tour- ists during the peak holiday period than the resort has capacity for. The result is that all accommodation and places of recreation are overpopulated and there is a general shortage of individual or collective sanitary facili- ties. REMEDIES (a) The siting of tourist holiday areas should be planned in the light of the physical constraints described above. Buildings intended for use by tourists should be planned and constructed within the framework of existing municipalities or of new municipalities whose establishment would be a viable proposition. (b) The construction of sanitary infrastructures should take into ac- count the total population during the tourist season, and adequate technical arrangements should be made to tackle special maintenance problems resulting from seasonal operations, in particular, drainage systems that become choked because there is not enough flow of water to maintain a self-cleansing vel- ocity and prevent deposits forming in the sewers. Arrangements regarding water supply, and especially construction of reservoirs, should be broad enough to take into account not only the peak consumer season but also the reduction in available water resources at the end of th e dry period. (c) The organization of public sanitation services should be suited to the needs of the population during the busy season; this entails making provision for alternative work for the personnel of these services during the quiet season. (d) Adequate legal, commercial, and technical arrangements should be made to avoid overcrowding of accommodation, especially in the most sensi- tive areas, which are usually camping sites, or to avoid accommodating tour- ists in areas that are insanitary or otherwise unsuitable for human habi- tation. (e) Special attention should be paid to basic food hygiene, i.e., super- vision of markets, abattoirs, and deliveries of foodstuffs of all types, regular inspections of kitchens, restaurants, and the personnel for cleanli- ness and warnings to foreign tourists about excessive intake of " exotic" 112 foods. The most critical types of f ood are foods, raw vegetables, fruit grown at ground fresh and smoked meats, and dairy products. well known: shellfish and sea- level such as strawberries, (f) Places of recreation such as bathing beaches should be situated well away from discharges of solid wastes or wastewater. Adequate security arrangements should be made and a first-aid service should be available in case of accident. Places that are dangerous for bathing or other sports should be clearly marked. (g) Public establishments such as theatres, restaurants!, casinos, or dance halls should conform with recognized standards for accident and fire prevention. The building of annexes to such establishments should be dis- couraged. (h) Foreign tourists should be given verbal or written information in their own language concerning the existence and availability of basic care services, such as first-aid services in the event of accidents. FINANCING OF RECOMMENDED MEASURES In the countries of the European Region, even those that are less ad- vanced technologically and economically, the recruitment of competent tech- nical staff raises no problems if adequate salaries are offered. Adoption of the proposed solutions largely depends, therefore, on the political will of the countries concerned to make the necessary planning and organizational efforts, and also on the mobilization of sufficient financial resources. In this connexion, the cost of health infrastructures and of operating public sanitation services should be borne by those who benefit directly from such services, i.e., the local population and seasonal tourists. The local popu- lation should pay the cost of providing those services only in proportion to the size of the resident population. The tourists should pay, either directly or indirectly, the equivalent of the additional cost of increasing sanitation services to meet the needs of the peak population. CONCLUSIONS The most acute problems of sanitation and hygiene in tourist areas are felt in Europe along the Mediterranean littoral . Other areas, however, must not be neglected. The countries concerned are making considerable efforts to deal effectively with sanitation in tourist resorts but a problem giving rise to considerable concern is that of unauthorized tourism, i.e. tourism outside the properly equipped areas, especially ~amping at unapproved sites. Provision of sanitary facilities for organized tourist areas should be ac- companied by closure of insanitary camping sites . 113 1. 2. SELECTED BIBLIOGRAPHY Salvato, J.A. Guide to sanitation in tourist establishments. Geneva, World Health Organization, 1976 Public Health Aspects of Tourism. Report on a Working Group. Copen- hagen, WHO Regional Office for Europe (document EURO 4005) 3. Wood, P.C. Guide to shellfish hygiene. Geneva, World Health Organ- ization, 1976 (WHO Offset Publication No. 31) 4. Guides and Criteria for Recreational Quality of Beaches and Coastal Waters. Report on a Working Group. Copenhagen, WHO Regional Office for Europe, 1975 (document EURO 3125(1)). 114 11. HEALTH HAZARDS ASSOCIATED WITH INTRODUCING NEW CHEMICALS IN INDUSTRY: PREVENTION AND CONTROL S. Forssman1 EVALUATION OF TOXICITY Size of the problem It has been estimated that every year more than 1000 new chemicals are introduced into industrial production throughout the world. Many of these substances are toxic. There is so far often not enough knowledge of their toxicity and of the principles of prevention of occupational health hazards and of exposure when industrial production is started. Occupational expo- sure to new chemicals during the last 20 years has often been related to the production and handling of plastics and polymers, while the production and handling of pesticides and herbicides have exposed large numbers of people to toxic organic substances. Research in industrial toxicology requires considerable resources in trained personnel and well equipped laboratories, and it is usually imposs- ible for an individual country, even with large resources, to tackle this problem alone. Thus there is great need for international cooperation in this field in order to meet research requirements and to avoid unnecessary duplication of efforts between research institutes in different countries. Principles of evaluating toxicity It is sometimes possible to estimate roughly the toxicity of a new chemical from a knowledge of its physical and chemical characteristics and from comparisons with substances having a similar chemical constitution. The next step in the evaluation of the toxicity of a new chemli.cal is to carry out tests on laboratory animals. Test animals are exposed to the chemical through inhalation, ingestion, injection, or cutaneous absorption. The air concentration or doses that will cause 50% mortality is first es- tablished. Animals are then exposed to smaller doses for some time where the change in metabolism, in cell and tissue structure, in vital functions (of circulation, respiration, etc.), and in behaviour are studied. When the basic information has been obtained the effect of the chemical in ani- mals of several different species is investigated. At this stage it is essential to determine whether the substance is so toxic that it should not be used at all in industrial production; further 1 WHO Consultant. 115 toxicological studies will then be unnecessary. This information must be made available to industrial planners. If, on the other hand, the toxicity is such that it is considered possible to use the substance in industrial production when reasonable preventive measures are taken, possible long-term effects are assessed, including the carcinogenic, teratogenic, and mutagenic properties of the substance. Investigation of the mechanism of action is also essential. Finally, the concentration that gives rise to no measur- able effect is determined. This concentration, obtained through animal experiments, is then used in establishing a maximum permissible limit for man when industrial production of the substance co1lllllences. Usually, assessment of toxicity of new chemicals is carried out step- wise according to a scheme such as that given below. A. Animal experiments 1. Acute (a) Single dose: LD50 Mode of application: inhalation, skin , Animals: mice, rats, Main effects: oral, intraperitoneal, eye rabbits, dogs (b) Repeated doses: 1-10 days' exposure Animals: mice, rats, rabbits, dogs Main effects: 2. Subacute 30 days' exposure subcutaneous, Mode of application: oral, intraperitoneal, subcutaneous, inhalation, skin Animals: mice, rats, rabbits, dogs Main effects: 3. Chronic 4. 90 days' exposure 6 months' exposure 2 years' exposure Lifetime's exposure 3 generations' exposure Animals: mice, rats, rabbits, dogs Main effects (e.g., chronic intoxication (pathology, biochemistry), carcinogenicity, teratogenicity, mutagenicity) Proposed maximum allowable concentration 116 B. Human exposure 1. 2. Experiments (a) Acute (b) Subacute (c) Chronic Occupational exposure (a) Occupation (b) Average concentration, range of concentrations (c) Main effects (e.g., incidence of intoxication) pre-clinical signs biological tests of exposure (e.g., presence of lead in blood) 3. Proposed maximum allowable concentration Laboratory exposure of human volunteer subjects under safe conditions is of value and may sometimes be carried out. When a new chemical substance is introduced in industrial production, epidemiological studies monitoring health and exposure and comparing ex- posed and control groups will be carried out. It is essential to have de- veloped methods for early detection of health impairment in occupational exposure. From the results of such studies, the proposed maximum permiss- ible limit for a toxic substance may be revised. A recent WHO expert committee on methods used in establishing permiss- ible levels in occupational exposure to harmful agents (1) reported on meth- ods for animal experiments and human observations used in different countries and principles for interpreting data on the uptake/response relationship and their application in recommending maximum permissible limits. Areas of industrial toxicology where further knowledge is needed are specified in the report. Recent trends in industrial toxicity Experience during the last 20 years has revealed unexpected effects from long-term exposure to toxic substances. The attention of research workers has therefore gradually become focused on the long-term effects of new chemical substances. It is especially important to know that life-long exposure to low concentrations of various substances will not affect the health of exposed workers and that, on reaching retirement age, their aver- age level of health will be the same as that of other industrial workers and that of the general population as a whole. Some chemical substances after 117 an exposure of 10-20 years may cause, or contribute to, the occurrence of cancer. Recent experience of some new drugs with unexpected teratogenic effects has stimulated research to uncover such effects in new chemical sub- stances introduced into industry, and increasing interest is also being shown in the study of mutagenic effects . Problems connected with carcino- genicity, teratogenicity, and mutagenicity have generally been investigated through expensive and time-consuming animal experiments, but much research has recently been devoted to developing new methods that will provide an answer in a shorter time, using either cell suspensions, tissue cultures, or bacteria , or by studying the influence of toxic substances on certain enzymatic processes. The classical occupational diseases, especially advanced cases with "typical" symptoms and changes, are gradually disappearing in many industri- alized countries because of efficient preventive measures. Research has therefore been focused on health deviations at an early stage and on devel- opment of methods for the detection of precursors of disease. When indi- vidual exposure to toxic chemicals is reduced through improved preventive measures, as in most industrialized countries, exposure will occur, but main- ly at low concentrations. This emphasizes the influence of the human fac- tors, "the host factor", in the etiology of occupational diseases. Indi- vidual sensitivity to chemicals plays a larger role and an increasing amount of research must be devoted to the causes of this sensitivity. For instance, constitutional enzymatic defects have been shown to be of importance. Research during the last 50 years has been devoted mainly to investiga- tion of the toxic effects of a single chemical substance in a particular working environment. Actual occupational exposure, however, usually involves the action of several chemicals or several occupational health hazards at the same time; consequently, research is now concentrated on the combined effects of several chemicals or of a chemical substance and other health factors such as physical work load, heat, noise, or psychosocial stress at work. The total body burden of occupational and nonoccupational exposure must also be taken into account. Occupational health hazards may be a contributing factor to nonoccupa- tional diseases. For example, cardiovascular diseases, especially cardio- sclerosis, are more common among industrial workers in the rayon industry who are exposed to carbon disulfide than in the general population or control groups. Epidemiological methods have gradually been introduced to study morbidity in occupational groups compared with control groups in order to detect the influence of health factors at work on the incidence of nonoccu- pational diseases, especially cardiovascular diseases and lung diseases . EVALUATION OF EXPOSURE It is important to evaluate exposure to toxic substances in industry for two reasons: (1) to provide background information for prevention of expo- sure; and (2) to ascertain individual exposure in order to assess the poss- ible health hazard to an individual. 118 The strategy of sampling is of great importance in carrying out indus- trial hygiene surveys. Samples taken at fixed sites will give information about the variation of exposure and the variation of concentrations of toxic substances in air in relation to production cycles, standards of ventilation, etc., at different times of the day, month, and year. All this information will be used mainly for technical prevention of exposure, firstly to elimi- nate peaks of exposure and then to reduce the general concentration of the toxic substance in the atmosphere of the working environment. PREVENTION AND CONTROL It is very difficult to assess individual exposure from analyses made at fixed sites. It is preferable to use individual samplers such as port- able pumps to obtain an analysis of the air to which an individual worker is exposed. This will give information on individual exposure and, when combined with a detailed job description, on the more and the less dangerous parts of the job, stages or cycles of production, and parts of the factory, as well as the human factors involved in using and maintaining preventive methods. Analyses of alveolar air, blood, or urine to determine concentrations of toxic substances or their metabolites will give better information on the degree of exposure of an individual than measurements of air concentra- tions at the work place. Finally, use of epidemiological m~thods for moni- toring health in relation to exposure will give valuable information on the exposure and is useful in controlling the maximum permissible levels of toxic substances. The main technical preventive measures cover (1) exchange of the toxic substance for a less toxic one, (2) use of completely closed systems, (3) use of specially designed ventilation in areas where toxic substances are being handled with emission of hazardous substances, and finally (4) improvements in the general ventilation at the work place. The efficiency of these tech- nical preventive measures must be controlled through regular monitoring of air quality, which will also be of value when controlling the "human factor" to ascertain whether or not the technical preventive measures are being properly applied and maintained. In addition, the following points must be considered in preventing and controlling possible health hazards arising from the introduction of new chemical substances into industry. First, the toxicity of the new substance must be known, especially the short-term and long-term effects in experimen- tal animals, the target organs, and mechanism of action; then, a maximum permissible limit must be established in a simple way. With this basic information, it should be possible, as a first step, to decide whether the substance should be used at all in industrial production or if the hazards are so great that its use must be prohibited. When a new chemical substance has received a health clearance for use in industry, the first steps in preventing possible occupational health 119 hazards should be taken at the planning and design stage o r the new indus- trial production process to prevent exposure. Industrial hygiene engin- eering methods will then be used in regular control to ensure that exposure is below the maximum permissible limit and creates no occupational health hazards. Regular air analyses and health examinations wi ll make possible further control of the health hazards. Epidemiological studies of exposed groups in comparison with control groups permit establishment of a defini- tive maximum permissible limit and, also at an early stage , to detect any health hazards not revealed in the earlier animal experiments . INTERNATIONAL ACTIVITIES There is great need for international cooperation in the prevention of occupational health hazards from toxic chemical substances, for instance, in developing methods for the evaluation of toxicity, establishing maximum permissible limits, air quality criteria, and for environmental and health monitoring. The International Labour Office (ILO), WHO, and the Permanent Commission and International Association on Occupational Health, especially, are con- cerned with the general prevention of occupational health hazards from ex- posure to chemical substances. Some of their activities of special inter- est in connexion with health problems associated with introducing new chemi- cal substances into industry are described below. WHO activities Recent WHO reports deal with problems of monitoring health of workers with individual exposure (2), methods of early detection of health impair- ment due to occupational exposure (3), and methods used in establishing per- missible levels in occupational exposure to harmful agents, mainly chemical toxic substances (1), while a WHO study group has considered the effect of habituation to toxic substances when the effect or sensitivity of a toxic substance is changing during exposure (4). Criteria documents have been established by WHO for several basic substances, and a manual of industrial toxicology has been prepared by WHO (5). In addition, the International Agency for Research on Cancer (IARC) publishes a series of monographs on chemical substances causing cancer.l A WHO European Regional Office meet- ing in 1973 was devoted to evaluation of toxicity and establishment of an information bank on toxicity data, and two conferences on methods used for establishing maximum permissible limits in the USSR took place in 1972 and 1974 in Geneva and Copenhagen respectively. 1 For a list of these monographs, the reader should consult World Health Organization Publications, Catalogue 1947-1973. Geneva, World Health Organ- ization, 1974, and the catalogue supplement for 1974-1976, published in 1976. 120 The epidemiology of intoxications in industry was t he subj ect of a WHO European regional office study in 1971, and courses on the use of epidemi- ology in studying the effects of toxic substances in industry were organized by the Regional Office in English in 1975 and Russian in 1976. During the last few years the need for a data bank of information about toxic chemical substances has become apparent, and the possibility of setting up such a bank was discussed by a WHO study group in 1974 and by a United Nations Environment Programme (UNEP) working group in 1975 (6,7). UNDP/WHO project on industrial toxicology in Poland An internationaI project on industrial toxicology was conducted in Poland from 1973 to 1977 with the aim of establishing a model national in- stitute for testing the toxicity of new chemical substances to be used in industry and a modern system for prevention and control of occupational health hazards from industrial production of new chemicals. The Institute of Occupational Medicine in Lodz, Poland, was set up as a national centre for industrial toxicology. An information system concerning the planned use of new chemical substances in industry has been organized to link in- dustry, the Institute, and the national health authorities, and an infor- mation centre on toxicology is being established at the Institute. For this project, international funds of about US$ 900 000 were made available and the Government of Poland provided 2-3 times as much in local currency. The Institute also offers facilities for determining the toxicity of new chemicals through animal experimentation. Great problems arise in exposing animals to specified concentrations of toxic chemicals in air, and special exposure chambers for this purpose are now available at the Institute. In brief, the Institute is well equipped to serve the community in solving the types of problem outlined in this article and to react speedily in assessing potential health hazards that inevitably result from the introduction of new chemicals and new industrial processes. REFERENCES 1. WHO Technical Report Series, No.601, 1977 (Methods used in establishing permissible levels in occupational exposure to harmful agents: report of a WHO Expert Committee, with the participation of ILO) 2. WHO Technical Report Series, No.535, 1973 (Environmental health moni- toring in occupational health. report of a WHO Expert Committee) 3. WHO Technical Report Series, No.571, 1975 (Early detection of health impairment in occupational exposure to health hazards: report of a WHO Study Group) 121 4. Review and appraisal of information on acquired tolerance in occupa- tional exposure to chemicals. Report of a meeting held in Copenhagen, Denmark, at the European Regional Office, 29 September to 1 October 1975 Geneva, World Health Organization (WHO document OCH/76.1) 5. Principles and methods for evaluating the toxicity of chemicals . Geneva, World Health Organization, 2 vols. (in press) 6. WHO Technical Report Series, No . 586, 1976 (Health hazards from new en- vironmental pollutants: report of a WHO Study Group) 7. The international register of potentially toxic chemicals. United Nations Environment Programme, 1975 122 Nairobi, 12. PERMISSIBLE LEVELS OF TOXIC SUBSTANCES VJ K .h .1 . . ric agin Several programmes of the WHO Regional Office for Europe are based on the philosophy of establishing or evaluating permissible limits for human exposure in the living environment. All proposals for the periodical medical examination of workers and for studies of the epidemiology of industrial intoxications are in a general sense devoted to checking the presumed hypothesis that certain levels of exposure to obvious hazards might be considered as safe, and that, once settled, permissible limits (threshold limit values, maximum allowable con- centrations, etc.) can be used as a basis for practical means of limiting exposures and for further scientific studies. These studies reveal what consequences of such exposure might still be hidden, and whether the philosophical approach was or was not correct when concensus on certain levels of exposure was achieved on the national or international levels. The advantage of the environmental health criteria accepted by WHO is the clear distinction made between independent scientific criteria enabling evaluation of health effects of exposure to suspected hazards and the eval- uation process itself, which leads to the definition of standards (maximum allowable concentrations (MAC), threshold limit values (TLV), etc.). The evaluation process contains many elements with different deg~ees of approxi- mation influenced by prevailing attitudes and other considerations of a non- scientific nature. It has been pointed out (1) that, "judgements and decisions by health and other government authorities are seldom based strictly on the available scientific evidence concerning the possible health hazard associated with a specific chemical or other agent. Political, cultural and economic con- siderations cause local, regional and national authorities to come to quite different policy conclusions when faced with the same scientific evidence (or lack of evidence) concerning a particular hazard. Some governments, for example, may adopt the attitude that it would take too long to accumulate sufficient knowledge as to the precise toxicity for man of substance "X"; they, therefore, restrict individual or other uses of this substance solely on the basis of any carcinogenicity observed in laboratory animals, regardless 1 Regional Officer for Environmental and Occupational Health, WHO Regional Office for Europe, Copenhagen 123 of the dosage or routes of administration and the consequent limitations of many of the procedures used. Other governments may find such decisions inappropriate because of the resulting interference with economic develop- ment and because they have assessed the risk involved as being relatively low". But for nearly all potentially toxic substances, reliable knowledge about the risk itself is inadequate. Ideally, "criteria are complete sets of quantitative exposure/response relationships for all environmental factors for different effects and for different populations, covering the whole range of exposure levels" (2J but new relationships may be revealed in future studies. WHO launched a large- scale criteria programme in 1972 (2,3) and it is encouraging to learn that many European countries, and also Canada and the USA have recently taken positive steps to improve their occupational and environmental control ser- vices. Priority has recently been given by a number of responsible bodies to compilation of all available knowledge about the more impor t ant pollutants, and several attempts have also been made to draw up inventories of toxic substances, for example, the United Nations Environment Programme (UNEP) has founded an international register for potentially toxic chemicals, which are estimated to number tens of thousands (4), and the United States National Institute of Occupational Safety and Health issues each year a toxic substances list, which includes some basic information on toxic sub- stances (5). However, in the USA the list of threshold limit values (TLV), i.e ., values to be implemented, comprises only about 550 substances , in- cluding 30 standards (6) . A similar list has been issued in the United Kingdom (8) with some small differences from the American list, and the Federal Republic of Germany has reached a similar stage (7). The USSR produced a list of 763 maximum allowable concentrations (MAC) in 1972 (9, 10) and the German Democratic Republic (11) and Poland have both issued comprehensive lists of MACs. It has been estimated that the number of potentially toxic s ubstances to be evaluated toxicologically is approaching 25 000. The number of new substances introduced yearl y is 4000-5000; approximately 10% of these need to be studied thoroughly; thousands of scientists are expected to be in- volved in their testing, and millions of animals will be required. Inter- national collaboration in the creation of information systems is urgently needed to provide comprehensive coverage of criteria and standards for sim- ilar substances in different countries. So far, attempts to reconcile dif- ferent approaches to the setting criteria and limits have progressed very slowly. PERMISSIBLE LEVELS FOR OCCUPATIONAL AND GENERAL ENVIRONMENTS There are striking differences between the recommended levels of per- missible exposure to hazardous agents in industrial toxicology (12). These can vary tenfold, or even SO-fold, between countries. The differences in MAC and TLV values are not due to differences in scientific background data 124 because, as pointed out by Hatch (13), "even when dose/response relation- ships have been defined and agreed upon by various countries through inter- national organizations such as WHO, these countries may dif fer in their interpretation of permissible levels (PL). The permissible level of a substance may be taken at a point in the dose/response curve that would prevent the earliest demonstrable change from normal behaviour. Alterna- tively, for economic and social reasons, permissible limits may be set at a higher level, namely to prevent diagnostic illness, or at an intermediate point between these two, so that the response would be kept below the level of detectable health impairment". Thus the differences lie not in the na- ture of the data obtained in one country or another but in the different interpretations placed upon them. For nonoccupational permissible levels to protect the general popula- tion against environmental pollution by toxic substances there are no such large differences in the scientific data or suggested limits because the approach of finding the most sensitive index criteria is now recognized by responsible agencies in many countries. In some countries scientists have kept the concept of threshold limit values, mainly developed for use in industrial toxicology by the late L.T. Fairhall. This concept was declared by Stokinger (14) to be a preferred alternative to MAC "which as a term was increasingly realized to be inexactly descriptive". But at that time there was a great deal of misinterpretation and confusion of communal and occupa- tional MAC values. It has been frequently mentioned (14,15) that some scientists tend to take into consideration any sensitive shifts, however small, in organisms lying inside the border of homoeostasis maint enance, As an illustration, Dinman (15) recently disagreed with Bustueva's inference that a deleterious effect is produced by very small concentrations of H2S04 mist in the air, causing a decrease in visual threshold and an increase in ability to perceive light changes. Dinman argues that as early as 1948 the same changes were shown to be produced by the passage of air across the cheek, which is a benign phenomenon. If one considers only pathophysiological responses, and applying this test for establishing harmful levels for occupational exposure, Dinman's view is correct. However, Rjazanov's school has stated that "because so many factors must be taken into account when permissible levels of a particular substance in the air or in water are established, the use of the principle of the limiting index is essential. In accordance with this principle, the per- missible level is determined on the basis of the most sensitive index. If, for example, the odour of a substance can be detected in concentrations that have no harmful effect on man or on the environment, permissible levels can be based on the threshold of olfactory sensation. If the substance has a harmful action on the environment in lower concentrations than on the human body, permissible levels are based on the threshold of action of this sub- stance on the environment" (16). In this case, the shifts noticed by Bustueva were a signal of encounter between man and factors not normally present in the air, dangerous, if not to the individual then to population 125 groups exposed to this level for a long time, who would be forced to react permanently to the presence of the factor . The r eaction is not harmful in itself but is a signal of possible hazardous consequences. This concept of establishing permissible levels on a relevant and most sensitive signal of undesirable biological encounter can be illustrated by data compiled recently (31) on the effects of S02 in air . One can see that the indexes of hazardous influence are of a very different type and any simple response or effect obtained from direct experiment can only have relative significance. For example, S02 pollution of air manifests itself in different ways, as shown in the following tabulation. Index Odour threshold Acute injury to leaves and shrubs Taste threshold 50% leaf destruction in alfalfa Deterioration in health of bronchitis patients Increased incidence of cardiorespiratory diseases Growth retardation and chlorosis of white pine; 89% of gardens injured Increased morbidity in man and animals; increased cardiovascular morbidity, hospital admissions (long-term exposure) 36% of gardens injured after 1 year's exposure S02 concentration in ambient air <EEm)l 0.5 0.3 - 0.5 0.3 0.3 0.15 - 0.2 0.1 - 0.15 0.02 - 0.04 0.015 - 0.05 0.01 - 0.02 The H2S04 mist concentrations in Bustueva's experiments were around 0.7 - 0.9 milligrams per cubic metre which roughly corresponds to S02 con- centrations of 0.2 - 0.3 ppm. Compared with the figures presented in the tabulation, these appear to be rather high concentrations and not sensitive enough to predict the many different hazardous effects. Thus, Dinman's criticism on the inadequacy of such sensitive shifts because of their benign origin is incorrect. 1 1 ppm S02 126 Recent developments have shown that the search for more sensitive "signals" of deleterious encounter between S02 and man should be continued to find the real threshold, which lies far below some existing permissible standards accepted in different countries for the concentrations of so2 in air. This varies from 0.5 - 0.1 ppm in the USA to 0.5 - 0.05 ppm in the USSR, 0.1 - 0.04· in Japan, 0.25 - 0.05 in Sweden, 0.5 - 0.06 in Czechoslo- vakia and the German Democratic Republic and 0.4 - 0.02 in Canada, the first figure being for short exposures, the second for exposure over months or years. The approach now advocated is based on the principle of finding the most sensitive signals of possible adverse effect ·on the level of biologi- cal reaction and this is also applicable in setting some occupational expo- sure limits, especially when pathogenesis is not clear. An alternative to these views is a concept based mainly on physiological indicators of dis- ease, e.g., occurrences of the same pathophysiological reactions that could be considered as the threshold value of harmful effect. This principle for defining environmental protection levels is questionable and only in rare cases applicable in setting occupational health limits, because indi- cators of diseases, according to Pavlov's views, are breakdowns of adapta- tion reactions that will lead to manifest, hidden, or delayed pathological changes. ONLY BIOLOGICAL CONCEPTS PROVIDE SUFFICIENT PROTECTION It is clear that throughout history man has functioned in a continually changing environment, and adaptation . t o th e change is a property of l i ving systems. But changes differ. Some of the changes, such a~ geophysical changes, are slow and adaptation has kept pace with them. Other changes are manmade; some of them can be classified as biologically advantageous and some cannot. Biological acceptability of changes in the environment is very important as the adaptative capacity of man is rather limited and the continued survival of the human species is in no way guaranteed. The whole complex of physiological reaction to natural changes in the environment is coded in the human genetic system and this has been built up over many generations, reflecting prevailing environmental conditions. But when environmental changes are biologically new in their impact and occur rapidly, the precoded information for physiological reaction is ab- sent or very weak. The first goal of environmental hygiene is to provide satisfactory living conditions. To facilitate this goal, i.e., reduction of disease to a minimum level, it is necessary to discover and standardize the environmental factors required biologically to maintain homoeostasis in the human organism. This goal is based on Rjasanov's concept of hygienic standards that sets the environmental conditions necessary for healthy living in urban and rural areas (20). The second goal of environmental hygiene is defensive; ~tis an at- tempt to set limits for biologically harmful changes in the environment. 127 Man's a c tivities, especially during the last century, have dramatically changed the natural order of substances in the surface laye r of the earth. Coal, oil, and gas accumulated over millions of years are now being consumed in ever-increasing quantities, liberating both heat and chemical substances that are discharged into air and water. Radioactive substances that were dispersed at low concentrations in the earth's crust are now concentrated for use as fuel, releasing both heat and radioactivity. Industrial and agricultural chemicals are being discharged to the environment in increasing quantities. The entire ecological system, including man, which developed over many millions of years, by obtaining energy only from the transforma- tion of solar energy, is today increasingly required to adapt to these drastic changes. The defensive role of hygiene is thus extremely important because in his previous history, man was exposed only to challenge from or encounter with other independently developed parts of the ecological system. Encounter with plague organisms, for example, a rodent parasite, gave rise to epidemics since man had not developed the necessary level of immunity to the organism owing to the rarity of such events in very early times. The development of complex human society brings people together in the creation of settlements and also brings man and rodent into close association; adaptation to this encounter has even now not been completed. Nearly all the diseases of pre- vious centuries have been of this type, i.e., the result of the absence of adaptation to relatively simple changes in the natural environment . Now, however, encounters are of quite another kind, involving chemicals, radiation, and other manmade distortions of the environment, and constitute a greater challenge to man's biological capacity to adapt; sometimes there are no coded mechanisms to cope with the challenge. When the change is so small that a reaction detectable on first contact subsequently disappears, one can assume real adaptation . This is a basic philosophy for setting all t ypes of threshold in toxicology. Sanotzky (18) states that practically all the changes in the environment have a definite threshold, regardless of the fact that the magnitude of some will be extremely small. Dinman (24) postulated that any biological interaction will be of zero probability if the number of molecules or atoms in the interacting substance is less than 104 per cell. If this is so, r eal adaptation is possible when environmen- t a l changes are quite slow and allow development of adequate reaction mecha- nisms within the limits of biological homoeos t as i s . More frequent, but undesirable, is adaptation to environmental changes through disease. The simplest case is the acquisition of immunity through illness, i. e ., after contact with infection. Occasionally in industrial hygiene workers are found to acquire an apparently higher resistance to irritation by substances such as H2 S, S02 , and dusts, but during close health inspection it is possible to detect hidden pathological changes (e.g., atrophic change in the mucous membranes of the bronchi) that produce false compensatory effects. All cases of manifest or hidden pathology represent consequences of high stress on adaptation mechanisms - inability to obtain a new level of homoeos t a sis in one generat ion. 128 Drastic changes require adaptation by evolution: the weakest will die out and there will be a slow accumulation of resistance by selection up to real adaptation in following generations. The most difficult case, now being extensively discussed in the litera­ ture, is whether adaptation is possible at all in the case of certain new chemicals or other environmental changes that man has not encountered before in his evolutionary development. Solar ultraviolet radiation shorter than 290 Nm is excluded by the earth's atmosphere. Man therefore has no inbuilt adaptation to ultraviolet radiation of shorter wavelength such as that now produced by mercury bactericidical lamps, welding arcs, etc. Many complex chemicals used as drugs possess strong biological activity because they are alien to the normal reactions of the organism and interfere with metabolism in unexpected ways. Sometimes such drugs simulate natural metabolites to such an extent that differences in their chemical structure can be very harm­ ful to different organisms.1 To the advantage of man, such substances are mainly used in eliminating micro-organisms and insects. The discussion and examples presented above show that from the point of view of health, only a biological approach is suitable for setting hygienic limits and standards. This is the main thrust of connnunal hygiene aimed at providing health protection for the whole population. The hygienic limits set for the general environment must protect all kinds of life and all parts of the population including sensitive, low-resistance groups, etc. In accordance with Rjasanov's concept, the limiting decisive criterion for one pollutant might be odour, for another damage to pine trees or a change in the aesthetic qualities of surroundings. For occupational exposure, the criteria might be different, adhering, however, to biological concepts. LEVELS OF RESPONSIBILITY FOR DECISION-MAKING Once we have obtained criteria with descriptions of different ecobio­ logical effects and direct hazardous effects on health we can consider them in different ways, taking into account the different levels of responsibility before existing individuals, population groups, national populations, and before future generations. The highest levels of responsibility in decision-making are conserva­ tion and proper development of human health and nature. Under the pres­ sures of industrial needs and technological development aimed at improve­ ment of living standards, people are sometimes inclined to accept a definite level of risk, and this can be a source of conflict and misunderstanding. Where and when should certain levels of risk be allowed? A WHO Scientific 1 Suggesting principles for the development of new bactericides and insecticides. 129 Group (3) s tated that "risk-benefit analyses are a matter for consideration by countries, so the acceptability of certain risk levels is out of the scope of WHO criteria documents". There is always a temptation to gain economic benefits by increasing the level of risk for the occurrence of harmful effects. In some countries, however, modern definitions of MAC values for occupational exposure aim at prevention of delayed hidden effects and defence of the health of existing and future generations. Other countries f ormerly declared pe rmissibl e levels only on the basis of detectable harmful effects in a stated number of working hours, but after discovering the explicit mutagenic and carcinogenic effects of certain chemicals, e.g., asbestos dust, they have reduced TLVs for these chemicals to approach those accepted in the general environment in accordance with the concept of the most sensitive biological index. Differences between old and new TLVs, as between countries, are usually based on levels of acceptable hazardl rather than on differences in background scientific data. In practice, the following broad protection categories might be defined. (1) Health of one man, or of a limited number of men, from a single exposure. (2) Health of one man, or of several men, from a limited amount of repeated exposure. (3) Health of a given portion of the working population occupationally exposed to certain hazards. (4) Health of random groups of working populations exposed occupation- ally to health hazards. (5) Health of random groups of working populations not occupationally exposed to health hazards. (6) Health of populations in settlements only. (7) Health of populations in settlements and condition of specific natural local resources. (8) Condition of natural resources as a whole, including human health. In thes e categories, it is implicit that genetic considerations are increas- i ngly i nvolved fr om l eve ls 1 t o 8. 1 i.e., an acceptable risk of development of certain hazardous health effects. 130 The ideal goal of health authorities is to obtain protection standards corresponding to level 8. But our existing set of environmental protection standards is in reality a combination of levels 6, 7 and 8. For example, with requirements for radioactive waste disposal we are accepting responsi- bility on levels 7 and 8. Some attempt has been made to limit highly per- sistent toxic substances but in industrial air and water pollution the limits are often only on level 6. Levels 1-4 are often considered in par- ticular cases of occupational health but level 5 is the most suitable cate- gory for that purpose. There is now a general tendency to accept greater responsibility for the future of mankind and natural resources, and it is hoped that international collaboration in this field will become increas- ingly successful. According to the principle of the most sensitive index already des- cribed, limiting practices in general pollution control increasingly con- form to the concept adopted by the WHO Expert Committee on Atmospheric Pollution in 1964 (19)1 which described the most stringent category level for limiting air pollution as "concentration and exposure time at or below which, according to present knowledge, neither direct nor indirect effects (including alteration of reflexes and adaptive protective reactions) have been observed". It is highly desirable to have unified single environmental protection standards for both the general and the working environments . It is to be hoped that this will be so in the future, but traditionally the theory and practice for limiting exposure to chemicals is derived from occupational health experience where the levels of responsibility accepted are usually from 1 to 5. Existing systems of standardization still permit two sets of limit values, or MACs, one for the general environment and the other for the working environment. Some countries have already decided that for selected chemicals, in spite of the considerable cost involved, the levels of acceptable occupational risk should be brought closer to that of com- munal hygiene for the general environment. Maximum allowable concentrations in occupational health were recently defined (18) as "concentrations that by their action on exposure of the human body, periodically or throughout life, directly or indirectly, will not cause the development of physical or mental disease (including latent or temporarily compensated conditions) or changes in the state of health that go beyond the limits of adaptive responses detectable by modern methods of investigation, either immediately or in the long term (in this or in sub- sequent generations)". 1 For details in setting limits for communal hygiene purposes see Izmerov (17). 131 This definition brings occupational MACs close to those for the general environment. The difference might be large when the toxicity of the rele- vant substance is not very high and delayed or hidden effects (mutagenic, carcinogenic, and chronic illnesses) ar e o f ] ow probabi li t y , but wh Pn th e substance is dangerous to health MACs for the general and working environ- ments will be close. CURRENT PROBLEMS IN ESTABLISHING PERMISSIBLE LIMITS It is of great importance to consider when the system of setting thresh- old limit values accepted by many countries can be retained for future use and when a more stringent approach is desirable. Although one system may be advocated, this does not mean that it is better than another system that is not advocated . In many instances some pathological changes might be considered insignificant, but, as in the case of mutagens and carcinogens, absence of apparent pathological changes in an individual does not neces- sarily confirm that exposure to a defined dose of a chemical is safe. According to Stokinger (14), "concentrations exist for all substances, and some concentrations exist from which no response of any kind may be expected no matter how long the exposure . . . " For the moment, many exist- ing TLVs are based on air-borne concentrations of substances or conditions under which it is believed that nearly all workers may be repeatedly ex- posed, day after day, without adverse effect. Because of the wide varia- tions in individual susceptibility, exposure of the occasional individual at, or even below, the TLV may not prevent discomfort, aggravation of pre-existing conditions, or occupational illness (18). In this context, it is clear that when the accepted TLV levels are en- forced pathological changes may occur in some sensitive persons, and conse- quently the TLV should be slightly below disease-producing thresholds for the majority of workers. Thus one of the necessary conditions for setting TLVs in the past was to some e xtent the occurrence of pathological or im- mediate pathophysiological symptoms, or some low incidence rate of the spe- cific occupational disease itself. United States Congress Document N92-241, 1972, includes a diagram that indicates that the lower border of adverse health effect is above physio- logical and other changes of so-called uncertain significance (Fig . 1). Physiological changes of uncertain significance, which usually manifest certain degrees of stress posed to adaptation mechanisms, formerly were not regarded as harmful. Also conditions described as compensatory and habi- tual (10) were sometimes deliberately excluded from analysis and were not considered as a definte signal of potential delayed adverse effect . Some of the existing differences between TLVs and MACs for the working environ- ment might be explained by differences in approach, but from current litera- ture it is clear that after acceptance in the USA of the Occupational Safety and Health Act of 1970 this approach is rapidly changing. A recent 132 Fig. 1 Schematic spectrum of biological response to pollution exposure mortality morbidity physiological sentinels of disease physiological and other changes of uncertain significance body burden of pollutant 1 adverse health effect _i_ conference on the introduction of "behavioural toxicology in setting limits" (15) showed that biological approaches and other changes of view on the role of biological signals is taking place. It seems that, more and more, the lower parts of the pyramid are taken into account when setting new TLVs. At a conference on behavioural toxicology in 1973 Stokinger stated (22) that "TLV are representing safe limits for industrial workers for a working life time and thereafter: we do not intend that a worker should retire from employment only to suffer from job-related diseases". So it is intended to extend the USA definition for protection of workers through- out their whole life. Delayed effects such as carcinogenesis, mutagenesis, and gonadotoxic effects, which influence also the next generation, are in- creasingly considered to be important in the establishment of TLVs. Some other new important concepts and considerations are included in the assess- ment of safety margins, ceiling values, and recommended measurement tech- niques, which make control more effective and should produce further reduc- tions in the levels of hazardous substances in working places. This revaluation process sometimes leads to the extreme conclusion that it is impossible to find thresholds at all, especially for carcinogenic substances, and to requests for complete exclusion of some carcinogenic sub- stances from the human environment. These views are somewhat extreme and do not take into account that some carcinogens are always present in the environment, for example benzopyrene, which occurs as a product of many natural processes and of frying and roasting food. 133 Logically, the goal is to prevent environmental carcinogens increasing the risk of shortening the normal lifespan. The occurrence of life- terminating cancer in old age should not lead us to conclude that all such cases are due to the effects of environmental pollution. We do not know of any human population or group of experimental animals where cancer as a cause of death at the end of the normal lifespan can be excluded. Another controversial point of view is that "there is no substance which under certain circumstances could not be dangerous or safe. There is no battery of tests, however elaborate, which can prove beyond challenge the complete safety of a chemical. For the toxicologists to apply the terms 'toxicologically insignificant' or ' negligible risk' to a set of observations makes a premature judgement in the wrong areas, by the wrong persons as to insignificance or acceptability" (30). This is equivalent to saying that there is a risk of death throughout life, but in medical statistics curves for risk of death plotted against age-groups of given populations are the only reliable yardstick available. It is very important to use them for showing the influence of certain changes in the environment on health and for evaluating risk. The acceptability of occupational health risk for working populations should, by definition, be on a level that will provide no distinguishable shifts in the risk-curves for everyday life . The ecobiological approach described above should not lead us to con- clude that there is an absence of thresholds as such. Naturally, permanent adjustment between organisms and their environment implies that any change in the environment will produce some changes in the organism. But there is, as in any balancing procedure, some level of sensitivity and some changes that fall within the boundary of natural system interactions. The latter we call "normal physiological reactions within homoeostasis", but these are limited to "natural" factors of the environment within certain "normal" ranges of change. We must then ask, what is "natural", and what is "normal". The threshold of permissible action in occupational exposure is, accord- ing to Sanotzky (18), a minimum concentration, exposure to which gives rise to changes in the person exposed that go beyond the limits of physiological adaptive response or a latent (temporarily compensated) pathological condi- tion. In other words, "natural" change in occupational health should ex- clude any detectable stress of adaptation mechanism to answer the definition mentioned above. Of course, one should accept as "natural" changes to which the organism can react as a result of acquired evolutionary experience . This approach has raised some discussion as to what should be regarded as the limits of normal physiological reaction (23), but this is beyond the scope of this paper . 134 DECISION-MAKING IN SETTING LIMITS Great difficulties sometimes arise when a non-biological approach is applied to evaluating the validity and reliability of sugges ted safe limits for toxic substances. The wide spectrum of new methods of probability testing up to modern heuristic analysis must be used to reach a definite conclusion in a reasonable time and for an acceptable expenditure. Statistical methods have to be used to evaluate the results of biologi- cal testing and also, because of the innate variability of biplogical pheno- mena, to describe relationships between different biological constants and criteria. This sometimes means accepting a lower level of accuracy and wider confidence limits than can usually be attained in the nonbiological sciences. Attempts are sometimes made to determine biological thresholds to closer limits than the original data provide for. Without employing the heuristic approach and relevant statistics, which are not yet well ad- vanced, estimation of a threshold for carcinogens requires an impracticable number of experiments and the problem becomes virtually insoluble. If, however, the studies incorporate temporary trial standards fo~ proving pur- poses, this and other such problems are no longer insoluble. By choosing proper criteria and using appropriate safety factors, it is possible to arrive at reasonable working values. The safety factors themselves are subject to study and more exact definition (32). The general solution to this problem consists of: (1) choosing a working hypothesis; (2) analysing criteria available and deducing working values that include a reasonable safety factor; (3) evaluating the validity of the assumption that the level chosen is below the threshold of hazardous health effects. The only way to solve this problem and avoid accusations of using an exposed population as "guinea pigs" is to make a definite overestimation of the threshold value for safety, implement it as a TLV, and the~ start scien- tific studies on whether the restrictions imposed could be reduced. This approach is of special importance in the case of new chemicals. It has been suggested (21, 25, 26, 27, 28, 29) that deductive methods be used for establishing safe non-action MAC value levels for new chemicals by means of some definite formulae derived through heuristic approaches and based on analyses of simple chemical, physical, and biological (LDso, LC 50 , etc.) properties. The formulae themselves are quoted in the literature and their use permits the investigator to find out quickly and fainly reliably a non-action level including safety margin coefficients. Calculated values allow simplification of further study of new substances to the following tasks: 135 (1) to proving whether the calculated MAC value real ly lies below the action threshold (checking of zero hypothesis); (2) to evaluating the magnitude of the safety margin coefficient in- cluded in the calculated MAC by carrying out simple experiments aimed at finding out for what multiple of the primary selected MAC the zero hypothesis is no longer true. This, in many cases, would be enough to establish a MAC for practical use. Time-consuming experiments aimed at evaluating the real risk to health (determining all kinds of threshold effects and disclosure of patho- genic mechanisms) might be carried out later when the interim MAC value is already established and in use. Health services would then be in a posi- tion to require industry to introduce stringent, but guaranteed, MAC levels from the initial use of a new chemical. Sometimes, if there is a simple and adequate "engineering" solution to cope with the problem, there will be no need for further intensive toxicological studies. In other cases, a full study will be necessary to reduce the safety margin coefficient to an acceptable minimum. While differences in approach to the problem of environmental health protection are rapidly disappearing, there is need for increased inter- national collaboration in this field in order to keep pace with the increas- ing number of potential environmental hazards requiring evaluation. 1. 2. 3 . REFERENCES Health hazards of the human environment. Geneva, World Health Organi- zation, 1972, p. 15 The WHO Environmental Health Criteria Programme, Report of a WHO meeting. Geneva, World Health Organization (unpublished document EP/73.1), p. 13 WHO Technical Report Series, No. 511, 1973 (Development of environ- mental health criteria for urban planning: report of a WHO Scientific Group) 4 . The international register of potentially toxic chemicals. Nairobi, United Nations Environment Programme, 1975 5. The toxic substances list, 1974 ed. Rockville, MD, United States Department of Health, Education, and Welfare, National Institute of Safety and Health, 1974 (including Rules and regulations subpart of Occupational Health and Environmental Control) 136 6. Stokinger, H.E. Industrial air standards, theory and practice. Journal of occupational medicine, 2_: 429-431 (1973) 7. Maximale arbeitsplatz konzentrationen, 1974. Kornrnission zur prilfung gesundheitschadeiche arbeitstoffe mitteilung X. Bonn, Harold Baldt Verlag, 1974 8. United Kingdom, Department for Employment, Her Majesty's Factory In- spectors. Threshold limit values for 1972; Technical data note 2/72. London, Her Majesty's Stationery Office, 1973 9. Sanitary norms and standards for planning industrial undertakings. Moscow, 1972 (report SN/245) (English translation in WHO document WHO/CWS/75.4) 10. Methods for studying biological effects of pollutants, a review of methods used in the USSR. Report on a Working Group, Moscow, November 1974. Copenhagen, WHO Regional Office f0r Europe , 1975 11. Arbeits hygienische Norrnen und MAC-Werte-GDR. Berlin, Verlag Tribune, 1974 12. Hatch, T.F. Criteria for hazardous exposure limits. Archives of environ- mental health,]:]_: 231 (1973) 13. Hatch, T.F. Bulletin of the World Health Organization, 47: 151 (1972) 14. Stokinger , H.E. Concepts of threshold in standard setti~g. Archives of environmental health, 12: 153 (1972) 15. Dinman, B. Workshop perspectives. In: Xintaras, Ch., ed., Proceedings of a Conference on Behavioural Toxicology. Rockville, MD, National Institute of Occupational Safety and Health, 1974 16. Sidorenko, G.I. & Pinigin, M.A. Establishment of safe levels of chemi- cals in communal hygiene. In: Methods used in the USSR for establish- ing biologically safe levels of toxic substances. Papers presented at a WHO meeting in Moscow in December 1972. Geneva, World Health Organi- zation, 1975 17. Izmerov, N.F. Control of air pollution in the USSR. Geneva, World Health Organization , 1973 (Public Health Papers, No. 54) 18. Sanotzky, J.V. Investigation of new substances, permissibfe limits and threshold of harmful action. In: Methods used in the USSR for establish- ing biologically safe levels of toxic substances. Geneva, World Health Organization, 1975, pp. 9-19 19. WHO Technical Report Series, No. 271, 1964 (Atmospheric p9llutants: report of a WHO Expert Committee) 137 20. Rjazanov, V.A. Current problems of establishing hygienic standards in the field of environmental health: Air pollution control, Report on an Inter-Regional Seminar, Moscow-Volgograd, 1967. Copenhagen, WHO Regional Office for Europe 21. Zaugolinicov, S. et al. [Normograms for establishing approximate MAC values for hazardous substances] Gigiena truda i professional'nye zabolevanya, .!_: 28-30 (1974) 22. Stokinger, H.E. In: Xintaras, Ch., ed. Proceedings of a Conference on Behavioural Toxicology. Rockville, MD, National Institute of Occupational Safety and Health, 1974 23. Zielhuis, R.L. Permissible limits for occupational exposure to toxic agents. Intern. Arch. Arbeitsmed., l1_: 1-13 (1974) 24. Dinman, B. Non-concept of no-threshold chemicals in the environment. Science, 175: 495 (1972) 25. Lublina, E.J. [Properties of correlatory links between molecular weight and maximum permissible levels for certain classes of organic compound as a function of their state of aggregation]. Gigiena truda i professional'nye zabolevanya, .!_ (1973) 26. Sanotzky, J.V. & Sidorov, K. [A contribution to a history of the hygienic standardization of harmful particles in the atmosphere of working zones in the USSR]. Gigiena truda i professional'nye zabol- evanya , .2_: 11-15 (1973) 27. Lublina, E.J. & Filov, V.A. Chemical structure, physical and chemical properties and biological activity. In: Methods us ed in the USSR for establishing biologically safe levels of toxic substances. Geneva, World Health Organization, 1975, pp. 19-45 28 . Ulanova, J.P. Toxicometry and prophylactic toxicology. In: Methods used in th e USSR for establishing biologically safe levels of toxic substances . Geneva, World Health Organization, 1975, pp. 45-55 29. Stabsky, B.M. Express methods, gigienicheskogo Nosmizovaja chimi- cheskich Veschestr. Gigiena truda i professional'nye zabolevanya, 1: 23 (1974) 30. Martin, W. & Stern, A. The status of air quality management standards. In: Inter-Regional Symposium on Air Quality. Geneva, World Health Organization, 1973 31. Prinz, B. Air quality standards and their application. In: Manual on urban air quality management. Copenhagen, World Health Organization Regional Office for Europe, 1976 (WHO Regional Publications: European Series No. 1) 138 32. Principles for evaluating chemicals in the environment: report of a Committee for the Working Conference on Principles of Protocols for Evaluating Chemicals in the Environment, the Environmental Studies Board of the National Academy of Sciences and the National Academy of Engineering, and the Committee on Toxicology of the National Research Council. Washington, DC, National Academy of Sciences, 1975 139 13. EPIDEMIOLOGICAL STUDIES OF AIR POLLUTION HEALTH EFFECTS 1 R. van der Lende AIR POLLUTION AND ITS EFFECTS ON THE HUMAN AIR PASSAGES In the search for health effects of air pollution there is a tendency to study primarily the effects of pollution on the lungs and air passages. There are, however, also more generalized effects of air pollution. A number of pollutants that are inhaled via the air are absorbed into the circulation, and can affect various parts of the body (e.g., heavy metals, carcinogens, etc.). Furthermore, pollutants in the air are deposited on land or in water, and thus may enter the body via the digestive system or skin. In this paper, however, only epidemiological studies of the effects of air pollution on the lungs and air passages are dealt with . Not all persons react to inhaled irritants in the same way. Clinical investigations have shown that two different types of sensitivity can be distinguished : so-called specific sensitivity and aspecific sensitivity. In people with specific sensitivity specific irritants give rise to an allergic reaction in the body by stimulating formation of specific anti- bodies. Depending on the place in the body where these antibodies settle (e.g., in the blood vessels or attached to cells), different types of aller- gic reaction occur. In the lungs and air passages the allergic reactions produce symptoms of hayfever, asthma, granulomatous reactions, etc. In people with aspecific sensitivity obstruction of the air passages may appear when irritants are inhaled in small amounts that cause no measur- able reaction in normal people. This sensitivity is called aspecific be- cause no single agent causes the reaction. People with an aspecific sen- sitivity (also called hyperreactivity) of the air passages may react to fog, tobacco smoke, perfumes, paint, sometimes even to cold air. Epidemiological investigations in the Netherlands on the frequency of disease of the air passages and the causes of these diseases, have shown that, depending on age, about 10-20% of the Dutch population has increased sensitivity for various types of irritating agents in the inhaled air (1). It is, therefore, important to take this sensitivity into account when dis- cussing the effects of air pollution on the air passages in man . 1 Associate Professor of Epidemiology, Institute for Social Medicine, State University, Groningen, Netherlands, and Head of Research Unit f or Epidemiology of the Dutch Organization for Health Research, c/o University Hospital, Groningen, Netherlands. 140 PURPOSE OF EPIDEMIOLOGICAL INVESTIGATIONS INTO EFFECTS OF AIR POLLUTION Besides laboratory investigations on toxic effects of certain agents that may be present in polluted air, it is also necessary to carry out epi- demiological investigations on the effects of air pollution. This is so, because laboratory investigations suffer from some serious drawbacks. First, they do not allow generalizations for the population as a whole since the persons investigated are practically always specially selected from the population and, furthermore, the number of people studied is generally too small to allow such conclusions. Secondly, and more important, is the fact that laboratory investigations are mostly carried out by experimental expo- sures of healthy people (or animals). This is certainly very useful if it is intended to study the dose-relationship of certain toxic effects of a suspected hazardous agent, but it is not sufficient for predicting the ef- fects of that agent in natural circumstances. The studies cannot predict the effect of this agent, in combination with other agents, in the general population (which includes sensitive individuals, old people, children, etc.). Yet, these effects are the only effects that can be used in setting so-called immission standards of pollution. Epidemiological investigations on effects of air pollution should, therefore, aim at studying the hazardous effects of specific agents (in com- bination with other agents) in random samples of the general population and should cover both qualitative and quantitative aspects. The qualitative aspects contribute to a better scientific knowledge of the way in which the agent influences health ; the quantitative aspec ts are important f r om a hygienic point of view (environmental hygiene) because criter~a for air pollution standards can be based upon such studies. INDICATORS FOR ADVERSE HEALTH EFFECTS ON THE AIR PASSAGES In previous epidemiological investigations mortality and ~orbidity statistics (derived from health statistics of all types) were ~ostly used as indicators of effects of air pollution. However, more information can be obtained from epidemiological field surveys. Indicators for adverse health effects on the air passages in such sur- veys are respiratory symptoms and lung function investigations. (1) Respiratory symptoms. These are detected by means of a standard questionnaire, for instance, that of the Medical Research Council of Great Britain, which is used for adults, or a WHO questionnaire on respiratory diseases of children (7). (2) Lung function investigations. It is generally assumed that ef- fects of air pollution (if they are hazardous for the air passages) will lead to decreased lung function. A decrease in lung function can be of a restrictive or an obstructive nature. 141 CHRONIC AND ACUTE EFFECTS OF AIR POLLUTION In principle, air pollution can affect the lungs in two ways. The first is the long-term influence of a certain concentration of pollutant, which will vary between certain limits. This may be called a chronic ef- fect. The second is short-term effects of higher concentrations of pollu- tants. There are some indications that these different types of action may cause different effects, even if the nature of the air pollution is the same. However, air pollution does not always have the same composition, even in the same area. Depending on the type of pollution source, the com- position of the pollution in the air not only varies from area to area, but also from period to period in the same area. This, for instance, can be caused by changes in the production process or the materials used or by various other conditions. In addition there are meteorological factors, which, even if the emission of air pollutants in a certain area is constant, initiate chemical and physical reactions between the various air pollutants. For these reasons it is extremely difficult to estimate the type and amount of pollution to which people living in a certain area are exposed, or have been exposed. Therefore, up to now, in many areas it has not been possible to do more than to conclude that there is "high air pollution". In general, that conclusion is based on the fact that a high concentration of sulfur dioxide (so2) or dust (suspended particles) has been measured. Therefore, epidemiological investigations that have been conducted have com- pared the presence of adverse health effects for areas with a difference in so2 concentration, without it being known whether the excess health effects found in the polluted area are due to so2 or to other substances. However, the studies at least give a general indication about the chronic effects of air pollution. As already stated, these results were obtained by comparing the fre- quency of disease in an area exposed to air pollution and in an area not so exposed, which means that populations from different geographical areas are compared. In such investigations it is very important to obtain good "standardization" for other causes of disease, for instance, causes connec- ted with social circumstances. On the other hand, investigators have tried to obtain information about effects of peaks in air pollution by comparing the frequency of disease (or the severity of disease) in the same population in periods when a pollution peak occurred and in periods with less air pollution. An example of such study is that made by Lawther in London (2, 3). In the Netherlands we were able to compare the lung function of a same population in a period when air pollution was exceptionally high and in a period when it was exceptionally low (4). Some other studies have been carried out in children (5, 6). 142 RESULTS OF EPIDEMIOLOGICAL INVESTIGATIONS CONDUCTED UP TO NOW Up to now, most epidemiological surveys on effects of air pollution have studied geographical differences in disease of the air passages. The conclusions can briefly be summarized as follows. In areas with high levels of air pollution (in a general sense, mostly without clear specification of the real type of pollution) there is a higher frequency of some respiratory symptoms such as chronic cough and chronic expectoration, a higher frequency of exacerbations of chronic bronchitis, and a higher frequency of absence from work. Some of the studies also in- dicate that inhabitants of polluted areas suffer from a higher frequency of symptoms of dyspnoea. A number of investigators have also found a decrease of lung function related to long-term exposure to air pollution but others could not verify such effects. In practically all of the investigations the value of the conclusions is limited by the cross-sectional nature of the study, i.e., they were con- ducted once only. In such cross-sectional studies it is not possible to guarantee that the populations investigated are not in some way selected. For instance, it is possible that people who are prone to respiratory dis- eases are inclined to move away from an area with high pollution. If a cross-sectional study is carried out in such an area, the people who would show the effect that is to be studied may have moved, and the erroneous conclusion may be reached that there are no differences in, for example, mean lung function or the number of respiratory symptoms between populations living in a polluted area and in a non-polluted area. Therefore, some in- vestigators have started longitudinal investigations to follow up the health status of populations in both types of area. Thus it is poss~ble to test the theory that there will be a higher frequency of health disturbances in the course of time in a certain polluted area than in a non-polluted area . It is important that this type of epidemiological investigation should be conducted more frequently than has yet been done. Furthermore, we must aim to study the influence of various types of air pollution, even though it will not be an easy task to define exactly the dominant air pollution in a certain area. Only in such way will it be possible to obtain data, per- mitting a prediction about the health effects of various types of air pollu- tion. The investigations should preferably be carried out through inter- national cooperation. The WHO Regional Office for Europe and the European Economic Community (EEC) have already initiated such studies. In a WHO Regional Office for Europe investigation a cross-sectional study on effects of air pollution in children was carried out in various European countries. The study was designed to seek differences in respira- tory symptoms and lung function impairment for areas suffering air pollution but differing with respect to sulfur dioxide and smoke concentrations . Socioeconomic differences between the various countries have a large influence on the final results and the same will be true for similar studies carried out by an EEC study group in a number of Member countries. Both 143 ___J___ investigations were very useful in showing the types of problem that arise in conducting elaborate international studies. As part of a UNDP/WHO proj- ect i n Romania, cross-sectional epidemiological studies have been carried out in a number of areas differing with respe ct to sulfur dioxide, dust, and other pollutants. In the course of a UNDP/WHO project in Spain, studies were carried out in Bilbaol and Madrid. Districts differing in the type and amount of air pollution were selected in each town. Within these districts, epidemiolo- gical studies on the frequency of respiratory symptoms and lung function disturbances were carried out in groups of children. All investigations were conducted according to a uniform protocol developed by the WHO Regional Office for Europe. At present, plans are being made to extend these inves- tigations to various other parts of Spain having different types of air pol- lution. As yet, very few epidemiological investigations have been conducted on the effects of short-term exposure to air pollution. Results of investi- gations in Vlaardingen (4) suggest that the effects on the air passages of short-term exposure to high concentrations of the usual air pollutants dif- fer from those due to long-term exposure to the same pollutants. Except for the experience with adults in Vlaardingen, only in a few investigations in children have Lomparative surveys been conducted on the frequency of res- piratory diseases during periods with different amounts of air pollution, rather than in areas with different amounts of air pollution. Such epidemi- ological investigations on the short-term effects of air pollution should also be carried out in populations that are exposed to various types of air pollution. Investigations on short-term effects can, in principle, be conducted in two ways. (1) The first method is epidemiological field surveys carried out several times in the same population during periods differing with respect to air pollution concentrations. These types of study can, with good planning, be conducted on the same schedule as the above-mentioned longi- tudinal studies on chronic effects. An example is the investigation in Spain referred to above, in which children are studied in spring and in autumn, two periods of the year when air pollution concentrations in the study areas differ greatly. (2) The second method is the so-called diary investigation. In this type of study a number of individuals are asked to keep a daily diary, about the respiratory complaints they have on that day compared with previous days or compared with their "usual condition". Such studies should be carried out over a long period. At the end of the study an analysis shows whether 1 The reader is referred to the article by Bouscaren, where the Bilbao investigation is discussed. 144 an increase in respiratory symptoms (or a deterioration o f respiratory con- dition) appears at the same time as a short-term increase i n the air pollu- tion concentration. This type of study is, however, very difficult to conduct because it is not easy to persuade people to make re&ular daily entries in the diary. Furthermore, it is very difficult to verify the subjective information in the diary through objective investigations such as regular lung function examinations. However, with much effort it is possible to carry out such studies. This was proved first by Lawther (2) and later confirmed by Wever et al. 1 BIOLOGICAL MONITORING We have seen that in order to obtain a better knowledge of the influ- ence of various air pollutants or combinations of such pollutants, it is necessary to carry out epidemiological field studies. Only on this basis is it possible to specify acceptable maximum immission concentration (MIC) values, that is, the concentration of a certain type of air pollution that can be allowed in the ambient air. At present, such air pollution stand- ards are mostly established on the basis of laboratory experiment or on the basis of the so-called maximum acceptable concentration (MAC) values in work places. This is very dangerous for the following reasons. (a) MAC-values are mostly based on experiences with healthy people, who are only exposed to the concentrations of pollution during a working period of 8 hours (or on experiments with animals). (b) The complex of chemical and physical reactions that can occur between various pollutants in the ambient air, together with the effect of prevailing meteorological conditions, make it very difficult to predict what will happen in the air and whether the ·effect on the human air pas- sages will differ from the results of laboratory experiments with single pollutants. Therefore, risk associated with specific air pollution situations should not only be estimated experimentally but also studied t~rough in- vestigations carried out under naturally prevailing conditions in the field. Adequate knowledge about the effects of air pollution in natural conditions is necessary to provide a sound basis for air pollution standards. As long as there are gaps in our knowledge, we should not accept the view that sat- isfactory monitoring of ambient air quality can be based only on estimations of a few pollutants. Arrangements should be made to conduct biological monitoring, together with the chemical control, of the ambient air. This can be done, for instance, through examination of fields growing plants that are sensitive to various types of air pollution and also througp the regular health control of random samples of the population in threatened areas. 1 Unpublished data. 145 As regards the effects of air pollution, it would, for example, be very useful to measure regularly lung function in a random sample of the population in areas with high levels of air pollution. If well organized, this work would not require much time and would be considerably cheaper than elaborate chemical monitoring performed on a continuous basis. It is clearly necessary for epidemiologists to carry out investigations of this kind if progress is to be made towards effective control of air pollution and protection of the population. CONCLUSIONS For the future, there are three priorities for epidemiological inves- tigations on the effects of air pollution. (1) To conduct longitudinal investigations on the chronic effects of various types of air pollution in large random samples of the general popu- lation. Such investigations should be carried out in areas with dif ferent types of air pollution, preferably within the framework of a well directed international project. (2) To conduct epidemiological investigations on acute effects of various types of air pollution in large random samples of the general popu - lation. In the same areas mentioned under (1) above, periodical investi- gations should be made in periods of high levels and low levels of air pol- lution . In addition, "diary investigations" should be conducted in a smaller random population sample during, for instance, one year. Such studies must employ uniform methods, and there should preferably be inter- national collaboration in these efforts. (3) In areas with new industrial settlements, regular examinations should be made of lung function in a large random sample of the general population before the air becomes polluted. In this way, a basis can be established for comparisons of regular lung function measurements made in the same people when there is air pollution. Lung function measurements should also be made in a control group that is not exposed to air pollution. REFERENCES 1. Van der Lende, R. et al. Epidemiological investigations into the in- fluence of smoking and atmospheric pollution on respiratory symptoms and lung function disturbances. Pneumonologie, 149: 119-126 (1973) 2. Lawther, P.J. Climate, air pollution and chronic bronchitis. ceedings of the Royal Society of Medicine, 51 : 262 (1958) 146 Pro- 3. 4. 5 . 6. 7. Lawther, P.J. et al. Air pollution and exacerbations of bronchitis. Thorax,~: 525-539 (1970) Van der Lende, R. et al. A temporary decrease in the ve~tilatory func- tion of an urban population during an acute increase in air pollution. Bulletin de physiopathologie respiratoire, 11: 31-43 (1975) Watanabe, H. et al. Effects of air pollution on health. Report No.l: Peak flow rate and vital capacity of primary school children. Reports of the Osaka City Institute of Hygiene, 1-Q: 32-37 (1964) Shy, C.M. et al . schoolchildren. Air pollution effects of ventilatory ftmction of US Arch. environmental health, 1:]_: 124 (1973) Study on chronic respiratory diseases in children in relation to air pollution, Report on a Working Group, Dusseldorf, 1974. WHO Regional Office for Europe, Copenhagen, 1974 (document EURO 3114(3)) 147 14. MANPOWER REQUIREMENTS IN ENVIRONMENTAL HEALTH FIELDS IN EUROPE S. Arceivala1 INTRODUCTION Environmental health protection work in Europe is based on experience gained over a period of 75 years, but during the last decade or two the field has widened so rapidly, becoming so extensive, that manpower require- ments are difficult to estimate with any degree of confidence. Historically, environmental health protection work developed in response to the need for safe public water supplies and hygienic disposal of liquid and solid wastes. While these problems continue to demand our major attention, environmental health planning now takes place in an entirely different context. Because of increasing urbanization and industrialization throughout the world, planners are obliged to think now in terms of resources - water, air, and land - and at the same time to take into account the multifaceted relation- ships between man's health and his ecological habitat. Environmental health manpower planning in Europe for meeting present and future requirements is of considerable interest for administrators and educators. They would like to ensure that the personnel needs of their programmes can be met and that their training facilities will always be able to produce the required numbers and types of personnel needed. Practically all countries today have 2a national manpower policy and most have some form of manpower planning . However, the extent to which health manpower planning is carried out, and the methods used, vary widely in different European countries. There is even more variation in environ- mental health manpower planning, which is a relatively new discipline. Here, the true situation is not known in many countries and national esti- mates of future requirements are often not available. In some countries, such as the USSR, estimates are made only periodically and for certain cate- gories of personnel to help adjust educational programmes to the country's manpower needs. Thus the current situation in Europe is one of great di- versity. 1 Project Manager, UNDP/WHO Project for Promotion of Training, Research, and Programmes in Environmental Engineering and Sciences at the Middle East Technical University, Ankara, and the Istanbul Technical University, Turkey. 2 See also Methods of estimating health manpower: in Budapest in October 1968. WHO Regional Office for 1969 (EURO 0289) 148 Report on a symposium Europe, Copenhagen, DIFFICULTIES IN MANPOWER ESTIMATION The organizational patters in the different countries in Europe are complex and vary considerably from one country to another. Generally speaking, in most countries there is a multiplicity of agencies each per- forming part of the total work to be done in the environmental health field, their interrelationships being governed by the traditional organizational patterns existing in each country. The categories of personnel involved are also not identical in all cases. Several categories of personnel per- form only part-time work in this field and in some countries environmental health personnel may be included in other fields for purposes of classifi- cation. Both horizontally and vertically, the availability of professional and auxiliary environmental health personnel has in general not been uniform, or satisfactory, and their deployment has, therefore, also been uneven. At times the functions and responsibilities of these personnel have not been matched by their training. It is therefore necessary to classify environ- mental health workers in order to match their skills to the work they are required to do, keeping in mind that differences in educational systems and terminologies adopted in different countries could give rise to mis- understandings. Even if we assume that, in spite of probable difficulties, present-day manpower requirements can be determined, future projections are difficult to make with any degree of certainty. A major handicap in this regard is inability to foresee a country's future environmental policy and the man- power demand it may generate. Legislative decisions can profoundly modify the rhythm of spontaneous growth, while employment policies, methods of working, extent of mechanization and automation also affect productivity and future manpower requirements. The division of work between professionals and auxiliaries is also undergoing continual change, resulting in correspond- ing changes in the balance of manpower (or manpower mix). It is therefore important that es timates of manpower requirements always accompany new legislation or proposed executive action, bearing in mind the interval between a decision and the achievement of results. This will help to ensure not only that manpower constraints do not become overwhelming, but also that there is no overproduction of manpower at some levels of per- sonnel in some categories. MANPOWER ESTIMATION METHODS Several manpower estimation metho ds are available to determine the type and number of personnel required for executing given activities. Present and future manpower requirements can be estimated if the activities can be reasonably well defined. Perhaps one could ask if a wide-ranging field like environmental health can really be defined. Besides, the mix of acti- vities undertaken and the extent to which a service is rendered may vary 149 considerably from one community to another. Consequently, manpower esti- mation methods are, broadly speaking, of two types: those which .are based on staffing norms or manpower models for individual activities in which a certain standard of service is implied, and others where questionnaire sur- veys are undertaken in existing agencies and future staff requirements esti- mated in the light of their proposed activities. Methods used in the medi- cal field are generally not suitable for most environmental health activi- ties where physical facilities rather than personalized services are involved. There is obviously no single optimum method for estimating manpower requirements. Experience in the environmental health field is particu- larly limited and it may be wise to use more than one method wherever pos- sible to confirm results or to obtain a range of likely staffing require- ments. Some of the methods that can be considered are as follows . (a) Staffing norms In the environmental health field use has sometimes been made of staffing norms, especially for operation of well-defined public utilities such as water and waste water treatment plants, solid wastes incineration plants, landfill sites, etc. The norms cover both the types and numbers of personnel required at different levels, and often bear a simple correla- tion with the size of the utility, e.g., ei ther the volume or weight of "product" handled ver day. Future staff requirements are readily esti- mated if information on the planned growth of the utility is available . Such staffing norms are, of course, based on a specified or implied standard of service and working conditions. Extrapolation of results to other conditions, to utilities with a much greater or lesser extent of mechanization and automation, for example, may lead to erroneous results. For this and other reasons extrapolation from one country to another may be fraught with danger, and national surveys must be conducted as far as possible to generate the required data . (b) Manpower models For public agencies engaged in a variety of activities and functions related to a sector of the environmental health field (e.g., air pollution control, water supply and sewerage, water quality control) more complicated staffing norms have to be developed by utilizing workload factors or coeffi- cients to estimate the number of man-days required to accomplish known tasks. Considerable efforts have been made in the USA and elsewhere to develop suitable equations using coefficients relating manpower requirements to selected parameters such as population, area, capital costs, number of dwellings, etc. For example, manpower requirements for a function such as issuing permits is found to be better related to capital expenditure while manpower for handling complaints and patrolling in the field is better cor- related with the population se rved. In this manner, depending upon the mix of functions involved, a suitable manpower model is developed for the activity as a whole. 150 For example, one such model is the Walsh - von Lehmden model1 used in the USA for predicting the required manpower fo r air pollution control activities. It takes into account the manpower required for 5 primary functions (e. g., inspections, monitoring, granting permits, etc .) and 10 secondary functions (e.g., administration, emission estimates, training, reporting, etc .). For each primary f unction, a so-called staff parameter , P, is determined from an equation correlating it with the area or popula- tion served or pollution sources. The manpower required for all primary functions (p) is then obtained by summation of the P values multiplied in each case by a coefficient to take into account its workload weightage. Thus, where 5 M = L P i = 1 P. = F. (area, population or pollution sources) l. l. The manpower required for each secondary function is obtained from the primary manpower Mp and another weight/age coefficiP.nt, C, is applied to it. Hence, for the general case, the model takes the form: 10 M = M + L C .F. (M ) . p l. l. p i=l All mathematical models are validated by comparing manpower predictions with actual manpower utilized in existing agencies, and the coefficients are "fine-tuned" if necessary. Detailed questionnaire surveyii; and follow-up visits in selected agencies are essential to generate the kind of informa- tion from which models can be built. In most countries manpower models have not been developed, and in those where they exist only a few environ- mental health activities have so far been modelled. Again, extrapolation of the results from one country to another is not desirable and recalibra- tion of the coefficients together with some modifica tion of the model may be called for. (c) Q;uestionnaire surveys Such s urveys are generally conducted in the agencies, utilities, and departments involved in environmental health work in a given area or country. They help reflect the realities of the prevailing staff situa- tion, the actual baseline, more closely than other methods since they take into account the specific staff structure of each case. Questionnaire surveys can, of course, only be conducted in existing agencies . When coupled with the other methods just described they can reveal inconsisten- cie s in staffing patterns between agencies perfo rming similar functions. 1 Estimating manpower needs of air pollution contro l agencies. Walsh, G. & von Lehmden, D., Washington, DC, Offi ce of Manpower Develop- ment, Department of Health, Education, and Welfare, Public Health Service / Environmental Health Service National Air Pollution Control Administration, 151 The inherent danger in utilizing such surveys for predicting future staff requirements sometimes lies in biased responses and subjec tive assess- ments of increased future activities and their proper staffing requirement. None the less, questionnaire surveys are used in several instances, some- times routinely, for determining future requirements. The utility of questionnaire surveys is enhanced if the data are ob- tained in such a manner as to permit the development of staffing norms and even manpower models of the type just described. To fulfil this objec tive the activities need to be sufficiently desegregated. The facility or ser- vice parameter should not be hidden in an aggregation of data . For example, the number of plant operators should be correlated with the size and type of treatment plant but not with "water resources management", which is the higher generic category. In the absence of such detail questionnaire sur- veys can only produce gross estimates of manpower required for the specific mix of activities in a community, making it difficult to extrapolate to other areas with a different set of activities. The degree of detail required in this approach might entail some difficulties in securing data and establishing correlations, but the effort would be worthwhile. Man- power forecasts can then be made with some degree of confidence for any new mix of services and facilities likely to be developed within a community over subsequent years. (d) Other methods Relatively crude but rapid estimates of manpower requirements can often be made using simpler methods such as, for example, ratios of personnel to population served to obtain order-of-magnitude figures, provided the ratios are applicable to the area or country in question. The use of fixed ratios under varying socioeconomic conditions can produce highly erroneous estimates. Manpower requirements have also been estimated indirectly as a pro- portion of running costs for operating a service or of capital costs of con- structing a facility. Manpower has a lso been related to the total receipts from sale of equipment, to the fees earned by consulting firms, and to the budget of agencies. Manpower requirements could perhaps be correlated in a global sense to the gross national product (GNP) of a country though the proportion of money allocated for environmental work generally increases with the GNP only up to a point since community concern tends to level off at some stage. Ratios between different types of personnel employed in an activity reveal the so-called manpower mix~ and enable the composition of a group to be determined if the key component of the group is known. However, changes in manpower mix may occur as the budget of an agency increases or as the scale of operations enlarges. Few data are available on most of the above methods to permit even rough estimates to be made of manpower requirements in the environmental health field in Europe. 152 PILOT SURVEYS IN EUROPE In view of the fact that manpower s tudies in the environmental health field had never previously been undertaken in the European Region, except on a limited scale, the WHO Regional Office for Europe undertbok pilot surveys in suitable areas in collaboration with governmental agencies in a few countries. The study was a cross-sectional one to obtain a picture of the pre- vailing situation through use of questionnaires administered py local teams in each pilot area. The areas studied were (1) the city of Leicester, England (population, 287 350; area, 73 km2), (2) 1he province of Bydgoszcz, Poland (population, 1.95 million; area, 20 956 km), (3) the city of Gothenburg, Sweden , and its surroundings (population, 458 000; area, 903 km2), and (4) the city of Frankfurt, Federal Republic of Ge~any, and the adjoining counties (population, 1.267 million; area, 922 km). In order to be able to identify in each pilot area various agencies involved in environmental health work, several activities and sub-activities which could constitute a comprehensive programme in this field were first listed. Broadly, the activities of importance in the European Region are as follows: 1 (1) water resources management, (2) land resources management, (3) air quality management, (4) solid wastes management, (5) protection of the urban environment, (6) protection of the recreational environment, (7) radiation control, (8) noise control, (9) occupational health, (10) food control, (11) epidemiological services, (12) training and research, and (13) supporting services. The functional responsibilities and the fields of activity of each agency were recorded , followed by data for their existing personnel at the professional, sub-professional, and lower levels . The princ~pal activity and functions of each individual staff memeber in the professional cate- gories was then recorded together with his educational background and extent of involvement (full time or part time). Data were also obtained for the manpower mix, vacancies and turnover rate, and the anticipated growth rate in each job category over the period 1973-80. In order to develop indices or correlations between staff and the extent of services rende~ed data for various items like area and population served, GNP, etc., were also recorded. 1 Accident prevention requires some activities that are an integral part of certain environmental health programmes but are not included in this list. 153 A total of 524 agencies in both the public and priva te sectors were surveyed in the four pilot areas between 1973 and 1974. Together, they employed nearly 20 000 workers a t all levels and served about 4 million people. 1 In summary, the survey results showed that a little over 0.5% of the population was directly involved in environmental activities at various levels. In spite of expected diversities between the pilot areas the total number of professional and middle-level personnel employed in them lay within the narrow range 1869 - 2200 personnel per million population (see Table 1). Engineering personnel amounted to nearly 30% of these personnel. Among professionals only, the break-down was: engineering, 66%; sciences and administration, 16% each; medicine, 2%. However, the number of personnel in each individual job category showed large variation between the four areas owing to differences in employment practices, educational systems, extent of activities, and other factors. Very nearly 1% of the GNP was being spent on personnel in three of the four pilot areas. The amount being spent annually on staff in these three areas ranged from US$ 22 to US$ 62.7 per person served. The overall manpower mix of professional to all supporting personnel varied from 1 : 4 to 1 : 6 (see Table 2) and was expected to change slightly in favour of more professionals within the next 5 years. Interestingly enough, the proportion of vacant posts was small, the average range being 2.5% - 6.1%, though in some individual categories the percentage was higher. The anticipated growth rate was found to range from 2.8% to 23 .7% over the period up to 1980. The primary objective of the survey described was to obtain a picture of the prevailing situation in the environmental health field in the four pilot areas using the questionnaire method. However, the results were not amenable to extrapolation to other areas for various reasons, the principal ones being that the selection of the pilot areas (which depended on the voluntary nature of the work involved) was satisfactory. With one possible exception, the areas were too small and generally unrepresentative of the countries as a whole . Furthermore, major differences lay in the extent of services rendered in the four areas. By aggregating the wide range of environmental programme components into relatively few "activities" the sur- veys were simplified but the relationships between the components and the types and numbers of manpower required were lost to some extent. 1 See Study on manpower requirements in environmental health, Report of the Second Steering Committee Meeting, Copenhagen, September 1974. WHO Regional Office for Europe, Copenhagen, 1977 (document ICP/SES 003). 154 Table 1 PROFESSIONAL AND MIDDLE-LEVEL PERSONNEL EMPLOYED PER MILLION POPULATION IN THE PILOT AREAS Number of personnel employed Personnel per million population Federal Republic Sweden United of Germany Kingdom Professional: Engineering 468 802 766 Medicine 41 36 35 Sciences 149 115 153 Administration 162 122 210 Total professional 820 1 075 1 164 Middle-level personnel 1 049 972 875 Total professional and middle-level 1 869 2 047 2 039 Actual number of persons included in each pilot survey 7 166 2 337 2 365 Table 2 OVERALL RATIOS OF PROFESSIONAL TO ALL SUPPORTING PERSONNEL IN THE PILOT AREAS Overall ratio of professional to Pilot Area supporting personnel 1973 1980 Frankfurt 1 : 6 .0 1 : 5.6 Gothenburg 1 : 4.0 1 : 3.9 Leicester 1 : 5.1 1 : 4.6 Bydgoszcz 1 : 4.0 1 : 3.8 Average 1 : 4 .8 1 : 4.5 155 Poland 548 36 158 103 845 1 355 2 200 8 174 all More studies are needed in different areas after remodelling the ques- tionnaires so as to sufficiently desegregate "activities" to be able to develop staffing correlations which can be extrapolated to other areas . This would give planners greater flexibility in utilizing the data for their own specific mix of activities . An interesting outcome of the pilot surveys, however, was that for each major job category a "profile " could be prepared indicating the job descrip- tion, the functions performed, the t ypical educational background of person- nel, and employment , turnover, and growth rates, etc.,for each pilot area . As an illustration, a typical profile of a "sanitary engineer" is shown in Annex 1. Its use in computing training requirements is discussed below. ESTIMATION OF TRAINING REQUIREMENTS As the timely development of appropriate training programmes is gener- ally the main purpose of undertaking manpower estimation studies, the metho- dology for such estimation must take into account the two major types of training activity: (1) for new personnel entering employment, and (2) for periodic retraining of the personnel already employed. Training requirements for new personnel entering employment are more formal, often involve university education, and need several years of advance planning to ensure the availability of trained personnel at the appropriate time. It is necessary to know qualitatively the type of functions performed and the principal activities in which personnel of a given category are in- volved. This is to ensure that the training programme has a bearing on the activities and functions performed. Quantitatively, it is necessary to know the new jobs in a category likely to be created in a given period as a result of an increased work pro- gramme, taking into account the average turnover rate on account of retire- ment and various other reasons. The following formula may be used to esti- mate the average number of new persons to be trained, P, to achieve a given staff increase in t years: where P = present staffing, 0 Pt= staffing required at end of t years, and q = average turnover rate. Turnover requirements vary widely between countries and between cate- gories of personnel. Variations range from about 5% to as much as 50%, and 156 at times these requirements can be greater than those for new posts likely to be created in a given period. Requirements for further training of existing personnel are generally met through short courses, which are relatively easy to plan. The facili- ties required depend on the type and frequency of such courses for a given category of personnel. This frequency may range from once in 2-3 or even 5 years, depending on the level of the personnel. Continuing education is, in fact, becoming a planned feature in some countries. As environmental concern increases the trend is towards greater specialization and develop- ment of skills in the use of more elaborate equipment and controls. The refresher training requirement, R, per year is easily estimated from the interval Fin years between refresher courses: R=l 2 Based on data in Annex 1 an illustrative computation is given in Annex 2 for one of the pilot areas to show how to estimate the number of new sanitary engineers requiring to be trained for entering employment and, thereafter, periodic refresher courses. The objective is simply to illus- trate the methodology rather than to arrive at any reconnnended numbers. Similar computations can be made for other areas and other types of person- nel once data of the type shown in Annex 1 are available. CONCLUSIONS The timely implementation of new training progrannnes and evaluation of existing ones is necessary to meet the rapidly changing needs bf environ- mental health work in the Region. Identification of gaps in manpower would enable both WHO and Member States to modify or supplement their current pro- grammes to make them more effective. Experience in the use of manpower estimation methods in the environ- mental health field is very limited, and in many countries fewl data are available to permit even rough estimates to be made. Pilot studies under- taken by WHO in the European Region have been described. More studies are needed to develop further the available methods to improve their reliability. In this regard, continuing work by both WHO and the concerned national agen- cies is necessary. 15 7 ANNEX I STAFF PROFILE OBTAINED FROM PILOT SURVEYS Pe rsonnel category Functional level Sanitary/environmental/municipal engineer Group I (professional level) Group II (sub-professional or middle-level) Item Employment rate pe r million population (1973) Group I Gr oup II To tal Turnover rate (%) Group I Group II Pos ts vacant (%) Gro up I Gro up II Ant icipa ted growth rate in employment, 1973-80 (%) Group I Group II Years of educa tion (typical) Basic Not at university level Unive r sity gr adua t e level Pos t graduate l evel Principal f un ctions per fo rmed by indica t ed percentage of personnel (1) Adminis tra tion and managemen t (2) Design and consulta tion (3) Trainin g an d research (4) Labo r atory se rvices (5) Opera tion and maintenance (6) Inspection and field work (7) Special surveys and investiga tions (8) Special se rvices Federal Republic of Germany I 13 - 5-6 - I so 12 . S 37 . S - - - - - 11.0 28 . 4 39 . 4 28 . S 5.5 6 7. 7 21.4 41.6 II 10 5-7 - - 11 10 75 - - 10 - s - 158 Sweden I 12 - 22.2 82.9 105.1 0 0 0 2. 7 22 .5 4 . 6 4 . 0 1.0 I 51 17 s - 17 - 10 - II 9-10 3 - - 11 54 - - 1 41 1 3 - I 82 - - - 18 - - - United Kingdom 38.3 59.2 97 .S 0 10 0 12 . 0 0 17.6 11 2 3 - II - - - - - - 100 - Poland 26.2 97 . 5 123.7 ll.O overall l 6. 8 ove r all 76.4 66 . 0 I 11 7.0 7. 0 4.0 4.0 5 .0 4-5 0-1 - I II 67.6 22 .4 22.4 45 . 3 2 . 5 - - 0. 7 - 7. 2 5.0 18 . S 2.5 3 .3 - 2.6 NOTES TO ANNEX 1 Personnel category The terms commonly used in different countries to refer to this cate- gory of personnel are sanitary engineers, environmental health engineers, public health engineers, and municipal engineers. In broad ~erms, they are all concerned with the "application of engineering principles to the control, modification or adaptation of the physical, chemical and biological factors of the environment in the interest of man's health, comfort and social wellbeing". 1 In the present text, the term "sanitary engineer" is used. Functiona.l level Sanitary engineers often enter the field at the group II level, where they participate in various professional, administrative, and technical activities in office or field work. They generally assist, under super- vision of group I level personnel, in planning, organizing, coordinating, and evaluating. They may also assist in training and conducting special studies. Their responsibilities may extend over a considerable segment of the environmental health programme. When they enter group I level they may have overall responsibilities and broad latitude in organizing their work and supervising and directing their staff. Educationa.l background In terms of years of education, sanitary engineers in the different pilot areas, in addition to their basic education of about 11~13 years' duration, also study for 3-5 years at university level to obtain a degree in sanitary, civil, chemical, or other fields of engineering. Postgraduate courses lasting 1 year or more, following the above degree programme, are often taken by engineers before recruitment or while in service in the sani- tary engineering field. Principal functions performed in pilot areas In the Federal Republic of Germany, Poland, and the United Kingdom the principal functions performed by sanitary engineers at the group I level are in administration and management, while at the group II level they are more involved in design and consultation work or in field work and investi- gations. In Sweden the pattern is similar in group I but a high proportion of group II personnel are in administration and management and in operation and maintenance work, and their educational background does not involve university level education. In the Federal Republic of Germany sanitary engineers at the group II level may have undergone middle-level training at a technical college. 1 WHO Technical Report Series, No. 376, 1967 (The Education of Engineers in Environmental Health: Report of a WHO Expert Committee), pp. 6-7. 159 PrineipaZ activities Principal activities of sanitary engineers include water resources and waste management in practically all the pilot areas. 160 ILLUSTRATIVE COMPUTATION OF TRAINING REQUIREMENTS FOR SANITARY ENGINEERS ANNEX II The following illustration is based on the Polish data for sanitary engineers shown in Annex 1. Positions at the group I and group II levels (i.e., professional and middle-level) are considered together since quali- fied engineers entering at level II may eventually be able to transfer to level I, The relevant data are summarized below. Numbers employed Growth rate, Turnover rate Group per million population (1973) 1973-80 (%) (%) I 26.2 76.4 1.0 II 97.5 66.0 !.O Total 123.7 Total numbers expected to be employed by 1980 are: Group I. 26.2 + 0.764 (26.2) Group II. 97.5 + 0.66 (97.5) 208 per million population. New entrants to be trained Average number of new personnel, P, to be trained annually between 1973 and 1980 is obtained from: p 1 1 (208 - 123.7) 7 + 2 (208 + 123.7) . (0.01), 13.7 per million population. Since some posts are already vacant, it is assumed that there is no unemployment surplus available or else that number would need to be sub- tracted from the above to obtain the number of new personnel to be trained. Refresher tra.ining Assuming that refresher training is needed for short periods once every 3 years, the number to be trained per year is: R = ½ (123.7 + 208) ½ = 55 per million population. 161 No. 1 No. 2 No. 3 No. 4 No. 5 No. 6 No. 7 PUBLIC HEALTH IN EUROPE Previous numbers Health planning and organization of medical care (1972) Chronic diseases (1973) Connnunicable diseases (1974) Glossary of health care terminology (1975) Myocardial infarction community registers (1976) Coordination of health and welfare in four countribs: Austria, Italy, Poland, and Sweden (1977) Training and use of dental auxiliary personnel (1977) A limited number of copies of Public Health in Europe are available to interested persons, on request, from the WHO Regional Office for Europe, Scherfigsvej 8, 2100 Copenhagen 0, Denmark. Public Health in Europe is issued also in French and Russian.