Occupational hazards in hospitals: report on a WHO meeting, The Hague, 20–22 October 1981

World Health Organization Regional Office for Europe Copenhagen ·�,.J,hle�( It I,.. "'l J' ( , • / I I It _,i. t. ( I ·� ( c; C 1 / '/ /J✓ /,) 11 _,. 1 / (1,'-YI ik{ .I' (;-? c:"'ivz._t'/ i..C EURO Reports and Studies 80 Occupational hazards in hospitals Report on a WHO meeting The Hague, 20-22 October 1981 I ICP/ WKH 007 ISBN 92 890 1246 3 © World Health Organization 1983 Publications of the World Health Organization enjoy copyright protection in accordance with the provisions of Protocol 2 of the Universal Copyright Conven- tion. For rights of reproduction or translation. in part or in 1010. of publications issued by the WHO Regional Office for Europe application should be made to the Regional Office for Europe , Scherfigsvej 8. DK-2100 Copenhagen 0. Denmark. The Regional Office welcomes such applications . The designations employed and the presentation of the material in this publi- cation 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. territory. city or area or of its authorities. or concerning the delimitation of its frontiers or boundaries. The mention of specific companies or of certain manufacturers' products does not imply that they are endorsed or recommended by the World Health Organiz- ation in preference to others of a similar nature that are not mentioned. Errors and omissions excepted. the names of proprietary products are distinguished by initial capital letters . The views expressed in this publication are those of the participants in the meeting and do not necessarily represent the decisions or the stated policy of the World Health Organization. PRINTED IN DENMARK ISSN 0250-8710 CONTENTS Page Introductio n .... ................. .. .... .. ....... .. ........................... .. ... ....... ... .... .......... .. Current state of hospital occupational health services in Europe 2 Bulga ri a .............. . Czechoslovakia ............ .. Fin land ........................... .. France ........ .. ...... ...... . German Democratic Republic .... Federal Republic of Germany .. Italy ..... Netherlands Po land .... .... . Spain ........ .. United Kingdom . Specific topics ..... .. ... ................................... .... ...... ...... .... .. .... ... .............. . Ergonomics. stress a nd shift work .......................... ............ .... ...... .. Exposure to physical factors in health service personnel ...... .. ....... .. Chemical haza rds in hospitals .. .. .. .. .. ....................................... .. Hospital hazards and the workforce . ......................................................... .. General.. .. .. ... .... .... .. ... .. ... .. .. .. ................. .. .. .... .................... .. .. ...... .. Specific .... .............. .... .. .. ................ ...... ......................................... . .. .. .... ....... ... .. Conclusions and considerations for the future .......... .. Data collection ..................... .. ...... ...... ............................ ..... . 2 2 J J J J 4 4 5 5 5 6 6 6 7 7 7 8 17 17 Environmental surveillance ........................ .... .... ......... ............................. 19 Health survei lla nce ................................ ........... ........... ... .... ..... .... ... ..... 19 Research needs .. .. ................................ .. 20 Organization of work practice ...... .... ............... ............... ... ................................. 20 Counselling.. .. .. ..... ....... ............................. ... .... ... .. .. .... .. ........ . ....... ... ... ..... .. ......... . 2 1 Education ..................................................... .. 2 1 Recommendations 21 References .. ... . ....... ... .... ... . . 22 Annex I Occupational hazards of the health professions - M. To/onen ................... 24 Annex 2 List of participants .. 67 INTRODUCTION A Working Group on Occupational Hazards in Hospitals was convened by the WHO Regional Office for Europe. in collaboration with the Government of the Netherlands. in the Hague from 20 to 22 October 1981. The meeting was attended by 13 temporary advisers from 11 countries of the European Region. as well as representatives from the Trade Unions International of Public and Allied Employees. the International Council of Nurses and Public Services International (see Annex 2). Dr J. van der Kolk was elected Chairman and Dr N. Tsaneva Vice-Chairman. Professor J .M. Harrington was appointed Rapporteur. The participants were welcomed by the Deputy Director for Inter- national Affairs of the Ministry of Health and Environmental Protection. Dr J . Kakebeeke. who emphasized the importance of the hospital service to the community and. therefore. the necessity of maintaining the health of those operating the service. Dr M. Mikheev. Regional Officer for Workers' Health. representing the Regional Director. referred to the WHO policy of giving priority over the next few years to monitoring the health of hospital workers. The Sixth Genera l Programme of Work included the objective: "To promote the health of working populations. to control health risks. and to promote the humanization of work". Hospital employees. various specialists work- ing under a variety of conditions, were exposed to overt and covert occupational hazards. The identification. evaluation and control of such hazards wen: essential. The objectives of the meeting were to: specify the occupational hazards to which professional and other personnel employed in hospitals were exposed: consider measures to eliminate such health hazards. The Working Group: reviewed the current state of hospital worker health programmes in the countries represented; considered specific papers presented by members of the Working Group; reviewed the basic approaches to identifying, evaluating and con- trolling the major hazards; recommended ways in which they could best be tackled at national and international level. CURRENT STATE OF HOSPITAL OCCUPATIONAL HEAL TH SERVICES IN EUROPE Reviews of the current situation of occupational health services (OHS) were received from Bulgaria, Czechoslovakia, Finland, France, the Ger- man Democratic Republic, the Federal Republic of Germany, Italy, the Netherlands, Poland, Spain and the United Kingdom . Bulgaria The organization of OHS in hospital is an integral part of the national, regional and local OHS. The centralized pattern is typical of the system adopted in the socialist countries of eastern Europe . Hospitals are being taken into account in the classification of working conditions now being introduced in Bulgaria. This includes a review of the working environment according to physical, chemical , biological, ergonomic and stress-related factors , as well as the development of monitoring procedures suitable for the evaluation and control of each of these factors. Particular attention is being paid to the ergonomic problems of health workers, the physical and mental load involved in their work , shiftwork patterns and stress . Czechoslovakia OHS are statutory and are carried out under the supervision of the Minis- try of Health; they are thus strongly integrated with the general health services and include preventive measures and curative treatment. The problem of occupational diseases in health service personnel is currently an important topic due to the advent of technical advances in hospital treatment facilities . The strenuous workload imposed on hospital personnel is a cause for concern and particular attention is now paid to the risk of infection, particularly viral hepatitis . Other areas of particular concern are the risks of skin damage, and exposure to halogenated hydro- carbon anaesthetics and ionizing radiation . 2 A number of epidemiological studies are in progress to evaluate the degree of health risk to hospital personnel , and this will be compared with risks in other industries as part of the new Czechoslovak classification system of hazards at work. Specific studies will evaluate the health of dentists and surgeons. Finland A national programme for the development of OHS has been established, partly through the Occupational Health Services Act of 1978 and partly in the form of a five-year plan. Supervision of various parts of OHS practice has been delegated to the labour inspectorate, the health authorities and the plant safety committees. A more important registration of occu- pationally related ill health is likely to ensue from these measures. This, combined with environmental monitoring procedures, will provide the basis for establishing research priorities to control occupational hazards. Particular attention is already being paid to the therapeutic use of poten- tially genotoxic materials and the risks involved for women of repro- ductive age. France Hospital staff comprise 7% of the working population and are covered by occupational health legislation. The public hospitals became subject to such legislation in 1960 and the private sector followed in 1965. The physician in charge of a hospital OHS must keep a check on the health of the staff, take measures to prevent ill health, and be a member of the hospital safety committee. Two thirds of hospital employees are female , and particular attention is being paid to the hazards of ionizing radiation, infections (particularly hepatitis B) and stress, especially among shift workers. German Democratic Republic OHS are an integral part of the state health services covered by legislation. Occupational diseases in medical personnel are reported, and these reports have revealed an excess prevalence of skin disorders in hospital staff compared with the working population as a whole. Hepatitis B infection is now less of a problem than in the past. Federal Republic of Germany OHS have been statutory since 1974. However, since 1956 the accident prevention regulations have stipulated that hospital staff have to be 3 examined when first employed and at least at yearly intervals thereafter. This regulation has been revised and the revision came into force in October 1982. The periodic medical review may now be made at up to 3-yearly intervals, except for certain high-risk groups where the periodic examination remains annual. Particular attention is paid to tuberculosis , hepatitis B, the vulnerability of female hospital employees, dermatoses and diseases associated with stress. Italy There is no structured service for occupational health within the services of public hospitals, which account for 80% of hospital beds. The Medical Director is responsible for all environmental measures and for the preven- tion of infectious occupational diseases . The public hospital is now part of the local health unit providing care for 50000-150000 patients and staff. Thus at local level occupational preventive programmes are incorporated into the general plan for community preventive health . At national level there is still some uncertainty as to the roles of the ministries concerned with health , labour and industry. Certain hospital-acquired diseases are eligible for compensation. Hos- pital personnel are required to submit to a pre-employment medical exam- ination, whilst periodic examinations are compulsory for workers exposed to ionizing radiation, as well as for food and laundry workers . Vaccination against tuberculosis and typhoid is mandatory, and certain work practices are specified for operating theatre personnel. Netherlands A company employing more than 500 workers is required by law to provide a nurse, while those with more than 750 employees must provide access to a physician. The requirements for industry will soon apply to hospitals as well. Occupational health nurses are considered to be the core of any OHS and require special training for such work. Particular attention has been paid to infectious diseases, especially tuberculosis , salmonellosis and hepatitis B, all of which must be reported to the regional public health laboratories. Concern over the sharp increase in resistant and multiresistant bacterial strains in hospitals has led to investigation of the possible mode of entry of these organisms into the hospital environment. It appears that some of these resistant strains are brought in by staff, while others are related to the unnecessary and ex- cessive use of antibiotic therapy. So far as physical and chemical hazards are concerned, the development of NEN standards (similar to the DIN system in the Federal Republic of Germany) should help to control risks to hospital staff. 4 Poland OHS are organized in a similar fashion to those in other eastern European countries. Nevertheless , the number of occupational diseases in health care and social welfare personnel appears to be considerable ( 17 .9% of all occupational diseases in 1980). Ninety per cent of these are infectious conditions, chiefly hepatitis B which is a particular hazard to nurses. Other diseases of note include tuberculosis, dermatoses and musculoskeletal disorders . Spain OHS have been compulsory for Spanish industries for many years , but a similar system of surveillance was not introduced in hospitals until 1973. The responsibility for OHS was given to the departments of preventive medicine, which are required to promote the health of hospital workers, provide a basis for environmental control, establish an infection control programme, and provide epidemiological data within the hospital and its health area. Certain occupational diseases of hospital employees are sub- ject to compensation. The OHS undertake pre-employment examinations, supervise working conditions in all areas including cafeterias and laundries, study absentee- ism rates and monitor ionizing radiation protection measures. The work of the OHS is, however, hampered by a lack of adequate premises and specialized personnel. Indeed, the services have little executive power and are further weakened by a general lack of interest on the part of hospital physicians. United Kingdom The Health and Safety at Work Act of 1974 brought all working people under the umbrella of health and safety legislation. Nevertheless , the provision of OHS in hospitals has been a slow and fragmented process. The National Health Service is now the largest employer of labour, with over one million employees, yet OHS for these workers varies from the well organized to the rudimentary. In 1982, the Department of Health and Social Security published a report formally approving the establishment of OHS in every health district, but financial constraints and a shortage of skilled occupational health personnel is likely to retard the development of a universal and comprehensive service. Where such services do exist in some strength, pre-employment health surveillance is provided for all employees with periodic surveillance under- taken for those considered at special risk . Occupationally related infec- tious diseases are on the decline, especially hepatitis B and tuberculosis. Epidemiological studies are in progress to evaluate the risks to health for 5 laboratory personnel. operating-room staff and nurses handling cytotoxic drugs. Further research is planned into the structure of hospital work. musculoskeletal disorders in nurses, the outcome of pregnancy in female hospital staff and the effectiveness of OHS in health districts . SPECIFIC TOPICS Ergonomics, stress and shift work Ergonomic problems of medical staff involve the use of medical instru- ments and monitoring devices , the design of hospital buildings , and the furniture used therein. The workload of hospital staff frequently exposes them to energy expenditure. postures and work practices that are far from ideal ( /) . For example, the lifting of patients is often done in an inappro- priate way . Prolonged standing. bending or kneeling can also affect operating-theatre staff and cleaners. Nursing duties have been analysed for energy expenditure and shown to be physically demanding - equivalent very often to moderate manual work. Emotional stress is a concomitant of working with the sick. the dis- abled and the dying . In addition a high degree of long-term memory, considerable vigilance and responsibility is a sine qua non for many health professionals. Surgeons, who are expected to possess these qualities, may nevertheless have to work long hours in overcrowded and poorly venti- lated operating theatres where waste anaesthetic gases may be ineffectively removed. Attempts to reduce these risks and monitor the effects are currently under way. Shift work carries its own well recognized sequelae of circadian rhythm disturbances. but such effects may be exacerbated by overtime working and attempts to function normally while suffering from lack of sleep (2). Exposure to physical factors in health service personnel The main physical hazards in the working environment of the hospital are electricity and electromagnetic fields. ionizing radiation. lasers, noise , vibration and heat. It is possible to control electrical hazards by the use of well established international standards for the installation, use and main- tenance of electrically operated appliances (3). Electromagnetic fields of high intensity have been used for many years in physiotherapy depart- ments . Similarly, surgical diathermy may create dissipated fields as high as 40 W /m 1 and these , in turn , may disturb the sensitivity of equipment such as electrocardiographs, electroencephalographs and cardiac pacemakers. 6 Maximum intensities for an alternating magnetic field in these conditions have been published ( 4). Laser beams also require careful screening to avoid operator exposure. Ionizing radiation sources. both sealed and unsealed, are in frequent use in hospitals . WHO has recently issued manuals on radiation protection in hospitals. drawing on the recommendations of the International Com- mission on Radiation Protection (5). Chemical hazards in hospitals Many of the chemicals used in hospitals are known to be genotoxic (i.e. mutagenic , carcinogenic and/or teratogenic). There is. therefore, a need to undertake well planned pregnancy outcome studies to clarify these possible genotoxic hazards among various occupational groups in the hospital. Such groups include operating-theatre personnel (6) , oncology ward staff ( 7), and workers in sterilization units (8). The findings of numerous epidemiological studies have shown an increased rate of spontaneous abortions in operating theatre staff and there is now reasonable evidence to suggest an increase of about 40% in the risk of spontaneous abortion in women exposed to anaesthetic agents. What is not yet clear is whether these anaesthetic gases , cytotoxic drugs or sterilizing agents cause excess cancer or increased congenital mal- formation rates . HOSPITAL HAZARDS AND THE WORKFORCE General The reports of hospital hazards by country revealed a remarkable degree of uniformity in Europe . The main differences lie in the OHS infrastructure set up to identify, evaluate and control these hazards . All the countries represented have well established and comprehensive health and safety legislation, although in a number of instances hospitals have only recently been considered worthy of specific attention. Whether the approach is centralized or decentralized, preventive specialists in all countries are concerned about the degree of risk incurred by hospital workers in the course of their daily employment. Some western European representatives noted the difference in outlook between the concern shown by preventive medicine practitioners and their clinical col- leagues as to the seriousness with which they viewed occupational health in hospital workers . Traditionally, hospitals have not been considered as 7 ranking in health risk with heavy industries such as mining, construction and manufacture . Consequently, less attention has been paid to studying hospital populations. In addition, there appears to be some confusion over who is responsible for such health care at central government level. Such administrative difficulties are not found in the eastern European countries where occupational health services are considered as part and parcel of health care in general. There was , however, little disagreement over what constituted the most important health hazards for hospital employees. All countries noted the need to control absence from work associated with such conditions as dermatoses and the potentially lethal, though rarer, diseases such as hepa- titis B and tuberculosis. Many representatives noted the need to evaluate the part played by psychosocial stress in the etiology of work-related illness and in all countries the predominance of women in the hospital workforce presents problems that warrant specific study. Chemical and physical hazards have received less attention than microbiological ones, though the threat to health may be greater. Chemi- cal hazards are ubiquitous and, in the future, particular attention needs to be paid to agents capable of influencing pregnancy or inducing cancer. Specific The following section deals with 13 aspects of the occupational health of hospital employees which the Working Group considered to be particu- larly important. In many instances insufficient basic data exist to evaluate the level of risk , but following the research recommendations of the Group control procedures should be instituted to limit morbidity and mortality related to occupational exposure. The Group was keen to emphasize, however, that it accepted the basic precept that the health of the hospital patient was of paramount importance. Following this assumption, it con- centrated on the health of those who work to ameliorate or cure ill health in others , but felt that iatrogenic disease , whether in patients or staff, should be excluded from the ensuing text. Ionizing radiation The hazards of ionizing radiation are far greater than those of any other "physical" hazard. Hospitals make extensive use of ionizing radiation both for diagnostic and for therapeutic purposes. A number of occu- pational subgroups are at potential risk, the most obvious being the radiodiagnostic and radiotherapeutic staff themselves, while the least obvious are ward cleaners, domestic staff and porters who may inadver- tently come into contact with radioactive material. 8 Notwithstanding these hazards the actual risk to staff is relatively low since internationally accepted standards exist for the use of ionizing radia- tion . These ICRP recommendations have recently been updated and incorporated in the WHO guideline manuals issued for hospitals, general practice and dental practice (5). Indeed. the classic studies of radiologists by Court-Brown & Doll (9) and Seltser & Sartwell ( 10) suggested that if a risk of radiation-induced cancer exists. it is more likely to affect the older radiologists who started work before modern radiation protection tech- niques were universally adopted. Such a conclusion, if valid. does not exonerate modern OHS from maintaining strict health surveillance pro- cedures for all workers designated as being occupationally exposed to ionizing radiation. It appears. therefore, that such hazards are largely under control and this certainly applies to the public hospitals. Some members of the Work- ing Group expressed disquiet at the lack of control that might exist in some privately funded hospitals. The Group also felt that OHS in hospitals should review their lists of designated radiation workers so that unclassi- fied but exposed workers, such as maintainance and domestic staff, could be incorporated into newer, more extensive surveillance procedures. Industrial workers in hospitals There is a tendency to consider hospital employees as comprising only physicians, nurses. scientists and technicians. Such errors result from considering hospitals as buildings consisting solely of wards. patients and beds. A hospital also houses cafeterias. offices, laundries. boiler rooms. electrical plant. plumbing sys tems. and often gardens. One assessment of this group of domestic. maintenance, paramedical. catering and adminis- trative workers suggested that they accounted for 609c of the total hospital workforce ( / /). The catering staff should be cared for in the same way as any similar group in industry. with particular care being taken to protect the health of the people they feed as well as to protect them from the hazards of the kitchen . Laundry workers are exposed to cleaning agents. heat and the ever-present danger of needles and glassware inadvertently left in clothes and linen. In addition. soiled linen might harbour microbiological hazards from the patient or the ward. The maintenance of electrical. plumbing. ventilation and heating systems may expose this workforce to noise. vi- bration, electricity and dust. Indeed the ducts of many hospitals still contain asbestos lagging, which should be removed and replaced with less hazardous material wherever possible. In addition to normal occupational health surveillance. some of these workgroups may also be subject to specific factory legislation relating to the type of work they do or the materials they handle. 9 Infections Health professionals are liable to come into contact with patients suffering from communicable diseases. Indeed, tuberculosis is a hazard for hospital staff in many countries. Pathologists and laboratory personnel appear to be at greatest risk and a number of epidemiological studies have noted excess rates of tuberculosis and hepatitis B among these workers. Particular concern was expressed about hepatitis B. Hospital staff frequently have an infection rate 3-6 times higher than normal and national prevalence rates for HBsAg, though low (0 . 1-0.6% ) in western countries, show marked regional and ethnic differences. In addition to laboratory workers, staff in haemodialysis units, blood transfusion centres, drug addiction clinics, dental surgeries and venereal disease units appear at special risk. The incidence of hepatitis Bis falling in the United Kingdom but rising in some other European countries. Active immunization against the disease is becoming available but there are no clear indications of how to deal with H BsAg carriers - or even whether testing for the presence of the antigen is a worthwhile procedure. Tuberculosis is becoming less of a problem but the risk remains for anatomy staff - particularly in the post-mortem room. Other infections are much less common but can be more serious. These include Lassa fever ; Marburg disease and malaria . The control and prevention of occupationally related infections has been the subject of a number of guidelines and booklets in recent years. WHO has produced one on the prevention of hepatitis in haemodialysis units and blood transfusion services ( / 2) and the Organization is actively involved in the special programme on safe measures in microbiology. which it instituted in 1976. A major step towards establishing guidelines for work with micro- biological agents is the categorization of risk from the organisms. Follow- ing this, it should be possible to establish the appropriate level of health surveillance for the exposed worker and to formulate contingency plans for dealing with accidents or infections among laboratory staff when they occur (/J) . It will never be possible to eliminate these risks so long as patients continue to have infectious diseases, but minimizing the risks is a practical procedure. One additional concern expressed by the Working Group was the increasing frequency with which antibiotic-resistant strains of bacteria were isolated in hospitals . Some of these organisms are highly resistant to a range of antibacterial agents and present a serious threat to the health of patients. particularly those rendered immunologically incompetent by the illness. Various theories exist concerning the cause of the increase in resist- ant bacteria, the main one being that the indiscriminate and excessive use of antibiotic therapies has accelerated the development of these new strains. 10 Derma roses Occupationally related skin disorders were noted by all members of the Working Group as being of particular significance. In the German Demo- cratic Republic one study revealed that IO I out of 134 occupational dis- eases reported were skin disorders, whereas national statistics show der- matoses constitute only 10% of all occupational diseases . In the United Kingdom statistics on dermatoses in hospital workers are not available but these constitute the largest group of occupational disorders subject to compensation. In a recent study 20% of a population of laboratory workers were noted to have skin problems, though only a third of those were truly occupational ( 14). The range of occupations in the hospital that could bring workers into contact with irritant or allergic materials is as extensive as the list of compounds themselves. In addition to laboratory workers, particular concern was expressed over the use of detergents and disinfectants by domestic staff and the problems of drug allergies in nurses . In particular, disinfectants of the phenolic, aldehyde and quaternary ammonium groups were considered likely to cause irritant or allergic dermatitis. Other derma- titic agents mentioned included detergents, formaldehyde, ethylene oxide, synthetic rubbers in surgical gloves, nickel, phenothiozines and a wide range of antibiotics. Prevention and control of such widespread skin disorders was con- sidered to be related to the exclusion, where possible , of potent allergens and the classification of susceptible workers . The provision of protective clothing and appropriate training schemes should limit the risk of skin disorders in the less sensitive handling the less irritative agents. For example, a rationalization oft he disinfection policy for the hospital could ensure the restriction of disinfecting agents to two or three compounds and also avoid unnecessary disinfection procedures in areas where they offer little practi- cal advantage . Laundering procedures could likewise be rationalized with the avoidance where possible of direct handling of the cleaning agents and the elimination of perborate compounds which, in the experience of some members of the Group, have caused severe skin disorders . Chemical hazards A large variety of chemical agents have been and are being used in hospitals as anaesthetic agents , chemical sterilants, drugs and cytostatic agents . Some of these chemicals possess high chemical reactivity (such as chemical sterilants and some cytostatic drugs), whereas some possess specific action on lipid membranes (such as anaesthetic gases). Until recently, :ittle thought has been given to possible adverse health effects from occupational exposure to chemicals in hospitals. II Anaesthetic gases in common usage include nitrous oxide and the halogenated ethanes or ethers. Some - such as diethyl ether, chloroform, trichloroethylene and fluroxane - are either flammable or considered to be so toxic that many countries have stopped using them. The absence of effective waste gas scavenging devices in operating-theatres has, in the past , led to excessive amounts of these gases in the ambient air of the theatre. Recent studies have suggested that theatre personnel may be at risk of increased spontaneous abortion rates or even congenital malfor- mations should they continue working in such areas during the early stages of pregnancy . Such effects, as well as possible hepatic, renal or central nervous system dysfunction were a matter of controversy but had been the subject of a number of recent reviews (15). Cancer chemotherapy is a relatively new technique but the inherent carcinogenicity of many of these agents is now giving rise to concern among those who administer them . Possible methods of assessing the effects of such exposure to mutagenic/carcinogenic agents in man include in vitro examination of the operators' lymphocytes and assessment , again in vitro, oft he mutagenic capacity oft he operators' urine (7) . Results so far suggest that sufficient amounts of these chemotherapeutic agents may be absorbed by nurses in oncology wards to produce such in vitro changes, though effective protective clothing and a greater use of safety cabinets can eliminate the effects noted in the unprotected groups. Chemical sterilants such as ethylene oxide and formaldehyde have also recently been found in some studies to be animal carcinogens or even possibly human carcinogens (8.16) . Finally, methylmethocrylate, a polymerizable acrylic resin, has come into widespread use in medicine in the last decade. It is mutagenic and may be a potential hazard for workers using the volatile monomer. It appears , therefore, that certain sectors of hospitals, such as anaes- thetics units, sterilizing plants and oncology service areas , require an extra degree of caution and protective measures with respect to the handling of certain chemicals. The scientific evidence on which to base recommenda- tions is in most cases fairly meagre, but until more is known about the hazards it would be prudent to minimize occupational exposure in the hospital. Fire and explosion The hospital environment contains many flammable gases and liquids as well as a surfeit of electrical apparatus. It was noted that electrical safety was frequently ignored in the normal course of work and the unsafe handling of gas cylinders and gas pipes was all too common. In addition, the availability and use of cigarettes by staff and patients add a further dimension to the risk of a catastrophic fire or explosion. In most cases, the 12 dangers are well known and the correct procedures for safe handling are well established. What is required is constant vigilance to ensure that new staff are fully aware of correct working practices and that this training is periodically reinforced during the course of their employment. Equipment should similarly be efficiently used and routinely maintained so that faulty apparatus can not itself be a source of static electricity, stray sparks or minor combustion . It was felt that there was nothing very esoteric about these hazards, nor was any new research required to establish the true degree of risk. What was needed was the rigorous implementation of established safe working practices; laxity in this area was the commonest cause of such accidents. Physical hazards A number of physical hazards have already been noted - particularly ionizing radiation and electromagnetic fields. One further hazard is worth noting: ambient temperature. Operating-theatre staff, in particular, may be exposed to high ambient temperatures for considerable periods of time. In one Czechoslovak study reported to Professor Kodat, it was noted that operating-theatre staff each lost approximately 1500 g in weight during a shift. Their energy expendi- ture of 133 W was expended during static work and meant that heart rates of97-l 20 beats/min were not uncommon . The more demanding the oper- ation, the higher the pulse rate. Little research has been undertaken to establish ways of reducing this high workload and of ameliorating the environmental conditions. It is clearly impossible to make the technical work of the surgical team easier - that would depend on the degree of surgical intervention - but certainly much could be done to ensure that such work is carried out in more favourable environmental circumstances. Psychosocial aspects Much has been said on the subject of stress and yet the topic remains a difficult one to tackle . In strictly scientific terms, the problems of finding reliable measures of stress reduction compromise researchers' ability to discover causal factors and thus limit the potential for minimization. Physicians, for example, have traditionally low overall mortality rates in most western ;;ountries, yet their suicide rates are phenomenally high ( 17). If doctors do suffer an excess of mental illness it is not entirely clear what the main etiological factors are. Physicians who care for patients have been noteri to be more neurotic than those who do not, but pathologists have been noted to have a suicide rate in excess of physicians in general. Anxiety in the course ofa physician's work may be heightened by therapeutic 13 failure. diagnostic difficulties. disrupted family life or the death or dis- ablement of patients - particularly the young. Such factors. though studied to some degree in doctors. have not received sufficient attention among other members of the health profes- sions. who might in fact be less able to cope with such stresses either because of a lower level of training or an inability to influence. to the same degree. the therapeutic environment of the patient. Furthermore, the organizational structure of many hospitals may limit the degree of self- fulfilment necessary to offset such stresses and this will be especially true of the lower grades of health professionals . Work may be performed to unclear job specifications. undertaken by junior staff, and meted o ut to an excessive degree due to staff shortages, low pay rates or insensitive man- agement. Added to this may be the chemical, physical and biological hazards noted earlier and the conflicts experienced by overworked staff as they try to equate their demanding job with social and family responsibilities . Such a state of affairs may create feelings of frustration, aggression, inadequacy and tension in the workforce whose only means of protest may be short-term absences from work. Such behaviour exacerbates the staff shortages and di ~.rupts the scheduling of work rotas. Nevertheless. short- term absences do occur among large numbers of the hospital workforce of many countries. Correction of these shortcomings and the amelioration of stress is not an easy task. Nevertheless, much could be done to improve management structures and working arrangements. The creation of small teams who would feel a group identity was often a valuable ploy. Shift work arrange- ments should be established with the collaboration of the shift workers, rather than imposed on them by an intransigent management. Special consideration should be given to part-time posts to accommodate women who wish tc combine useful work with raising a young family . Staff should be taught to recognize early signs of stress-related disorders in themselves and their colleagues. They should also be taught how to deal with such signs so that the effects can be recognized early and eliminated effectively. Health counselling is a crucial part of such a scheme and the OHS is uniquely placed to provide this service. Drug abuse Drug abuse among hospital staff is common in many countries, perhaps related to the psychosocial stresses of the job but also to the relative ease of access to drugs . Common agents are the psychotrophic drugs, especially narcotics. stimulants and anxiolytic agents. Such practices vary from country to country but the problem is probably more widespread than generally supposed. As yet there is insufficient information as to the cause or mode of use. but clearly tighter control should be imposed on the stocks 14 kept in wards and pharmacies. The practice of self-medication should be discouraged . The OHS should be the main source of assistance and ther- apy in such situations where controlled surveillance can be appropriately and confidentially maintained. Women workers Specific agents have already been mentioned as possibly fetotoxic or teratogenic but the predominance of female labour in the hospital war- rants a separate discussion of the problems of women workers . While it is impossible at present to promulgate "safe" levels for many chemicals , it should not be suggested that women of 1eproductive age be banned from working with certain agents or in specific hospital departments. Such an approach is simplistic and assumes that the agents concerned are relatively harmless to male germ cells - a most unlikely supposition. A more rational approach would be to reduce the levels of all potentially harmful agents to the lowest practicable level and to use only the least harmful alternatives. Meanwhile, major epidemiological research is required to study pregnancy outcome in hospital employees in order to quantify the true risk and provide a rational basis for prevention and control. The OHS should take the lead here so that such genotoxic agents are identified, eval uated, contro lled or eliminated . A study of female employees in France has suggested that "nervous fatigue" is the most frequent cause of ill health in workers under 30 years of age though, as they age, these women become most prone to gynaeco- logical, osteoarticular and endocrine disorders . The high rates of absentee- ism in younger women may be caused, at least in part, by the demands of family life, the need to care for children, and an inability to fit easily into the shift work pattern. Clearly, much work remains to be done to evaluate the needs of working women and to provide them with a healthier, more satisfying and realistic working environment. District health work Occupational health care for domiciliary health workers is a relatively new concept but in many countries in western Europe the organizational structure of the health service is district-based rather than hospital-based . The hospital is still likely to contain the major concentration of labour but the needs of community health workers should not be ignored. Many hazards to which they are exposed are common to those working in hospitals but specific hazards might include their relative isolation from the centre of therapeutic activity. They might, therefore, have to make decisions and take clinical responsibilities in isolation from their colleagues. 15 For example, the care of the housebound, terminally ill patient can involve great stress. In such circumstances, the lifting and handling of patients involves far from ideal conditions and is likely to be undertaken in unsatis- factory conditions - low beds, poor washing facilities, and minimal laundry services. In addition, the district health worker may encounter undiagnosed communicable diseases, or be vulnerable to assault by patients or people in the street in isolated rural or urban areas, where little opportunity !Xists for summoning aid. Studies on the specific hazards to community health workers are urgently required. Accidents and injuries Although neither national nor international statistics on accidents and injuries among health professionals are available, they are a serious source of morbidity in hospitals. Experience suggests that there are five main areas of concern. Cuts , lacerations and fractures are not infrequent sequelae to handling glassware, knives and needles, laboratory personnel, porters and laundry staff being at greatest risk . In one British study, three quarters of all injuries to laboratory technicians were of these types and similar results have been reported from Denmark and France (17). Back injuries figure predominantly in accident/injury statistics for nursing staff, while domestic staff more commonly suffer from falls . Without doubt the handling and lifting of patients is frequently under- taken in difficult circumstances and often without adequate assistance, either from other staff or from mechanical lifting devices. All nurses should be trained in correct manual handling procedures. Falls are not uncommonly associated with wet or otherwise treacherous floors or the wearing of inappropriate footwear (11) . Hospital employees are often unprovided with the same quantity or quality of personal safety equipment that would be demanded for similar jobs in industry. These include hard hats , safety shoes, protective gloves of various types , safety spectacles and protective overalls . There seems, there- fore, to be an unnecessarily high percentage of hand , foot and eye injuries, many of which could be avoided by the wearing of appropriate equipment. By the same token, the maintenance of mechanical and electrical plant is frequently deficient and this has been noted in several countries to be the cause of crush injuries or electrocution . Finally, hospital staff are occasionally assaulted by patients or their relatives . This is uncommon in the ward but is becoming an increasing problem in accident and emergency departments at night. The problem is now of sufficient magnitude in some western European cities to necessitate the permanent stationing of security staff in such places for the protection 16 of the employees. Little prevention is otherwise feasible as this is more a symptom of inner urban life than an inherent hospital hazard. Microclimate of the hospital This subject has been alluded to in other sections - particularly in relation to operating-theatres, kitchens, laundries and boiler rooms. It is worth repeating that the hospital does contain a number of specialized areas in which specific environmental conditions need to be considered, in terms both of patient care and employee welfare. For example, air conditioning systems may play an important part in maintaining a comfortable environment for both patients and staff. Never- theless, water-cooled versions of such systems in hospitals have been implicated in outbreaks of pyrexial illness. The causative agent may be amoebae or even Legionel/a spp. It 1s essential that such systems do not spread disease in environments where disease is supposed to be treated. Competent engineers should be employed to install and maintain all such systems, with or without routine microbiological monitoring of the inlet and effluent from the cooling mechanism . CONCLUSIONS AND CONSIDERATIONS FOR THE FUTURE It was unanimously concluded that priont1es for future work must be formulated and some major areas for consideration are discussed in this section, in order of priority. This list is not meant to imply that the later sections are unimportant. All are important but effective action concern- ing these subsections was considered to depend on the full execution of the earlier points . As an aid to these conclusions , the Working Group devised and approved the flow chart shown in Fig. I. The diagram charts the progress from early symptom-free exposure to a hazard through to overt disease, which may or may not be curable. The occupational health team has a function to perform at each stage, with the overall objective of reversing the trend from overt disease and, in the final analysis, eliminating the hazard altogether. Data collection The occupational health team should collect and analyse data on staff morbidity and mortality, including absenteeism and accident/injury stat- istics. These data must be complete and detailed enough to give sufficient 17 Fig. 1. The prevention and control of occupational hazards Occupational health team function Environmental monitoring Biological monitoring and medical surveillance Treatment and epidemiological surveillance - morbidity - mortality 18 Workplace-related events Health effects Exposure at workplace - chemicals - physical agents None - biological agents ·u Biologically significant exposure - chemicals absorbed - early (reversible) changes Early ~, Clinical diagnosis - measurable health effects ~, End effects - jiseases Late - unfavourable events, e.g. spontaneous abortions information for instituting preventive and subsequent control measures. National data are sometimes inadequate, vague and deficient but data collected at source must be useful enough to enable cause and effect to be linked and acted on. Such responsibility lies with the OHS and all such information must be confidential. If staff are allowed to attend accident and emergency departments , clinicians or primary care physicians, these data should be available, subject to the employee's consent. Without such complete coverage, the information gathered will be incomplete and unreliable. Environmental surveillance Monitoring the working environment is complementary to health surveil- lance. Both are necessary to efficient occupational health control. Particu- lar attention should be paid to the development and implementation of efficient monitoring procedures for ethylene oxide, formaldehyde, anaes- thetic gases and certain solvents, as well as physical agents such as tempera- ture , humidity , noise, vibration and electromagnetic fields. Monitoring for microbiological contamination is justified following an accident or sus- pected exposure. In addition, more attention should be paid in the future to the monitoring of hospital waste, including radioactive material, chemi- cals and solid matter such as sy ringes and needles . Such activities should be undertaken with the agreement of regional authorities and be compatible with national regulations. Health surveillance This should include not only the universal application of pre-employment health screeni ng, either supervised or actually performed by the occupa- tional physician, but also periodic health examinations, the scope, depth and periodicity of which should be governed by the risk assessment of the job. The detailed information collected should remain confidential and such screening would include biological monitoring and prophylactic vaccination schemes for certain workers. Such vaccinations might include Heaf/Mantoux testing ± BCG and immunization against hepatitis B, Salmonella infections and rubella. Some of these procedures might be considered mandatory, others optional. A particularly useful type of periodic medical examination is that undertaken when the employee returns to work after illness or an accident. While it is clearly impracticable to carry out such procedures on all such individuals, many OHS employ a system of screening all persons absent for, say, four weeks. In addition, they may wish to see all persons who have had a series of frequent short absences over a six-month period. 19 Research needs Many aspects of the health of hospital employees are under-investigated. A wide range of research projects are of high priority but a crucial prerequi- site for all such work is the efficient collection of complete and reliable data . However, individual hospital populations are frequently too small in themselves for valid epidemiological studies. Thus, consideration should be given to the grouping of data with neighbouring units at a regional , national or even international level. Areas of research considered to be of particular importance are: hospital infection data to compare differential morbidity rates in staff; pregnancy outcome studies of staff working in areas such as on- cology and pathology, and where chemical sterilants are used; staff absenteeism rates for both long- and short-term absences; development of new techniques for environmental and biological monitoring as a prelude to better control of hospital hazards; studies of the causes of work-related stress and the best means to counter such effects. These areas are those most deserving of study but there is a need for improved research and better data collection rather than just more of it. Organization of work practice In general, ergonomic practices in the hospitals are poor. Greater thought needs to be given to such matters during the design of hospital buildings, when such considerations are easier and cheaper to implement than after the building has been completed. In general, handling procedures for patients are inadequate. Furthermore, the lack of thought given to ergo- nomics is revealed by the bewildering array of electronic devices in some areas in hospitals . This suggests insufficient expertise to ensure that the operator is working at optimal advantage vis-a-vis the apparatus at his or her disposal. It is apparent that in many hospitals little attention has been paid to the most efficient patient care, with the best use being made of the numbers and quality of staff available. This could lead to staff stress due to over- work , poor scheduling of jobs and inappropriate linkage of the employee to the job. In short, a greater degree of flexibility is needed, combined with greater participation of employees so that their skills can be used to the best advantage of the patients. 20 Counselling An occupational health department is the ideal counselling body - an independent unit with confidential consultation facilities having broader knowledge and understanding of the work undertaken in the hospital than any other individual unit. Great emphasis was placed on the need to publicize this vital OHS function among hospital employees. Such a service is not only of inestimable value to the individual but also provides the OHS with valuable insight into the intricacies of job-person relation- ships that might not otherwise be obvious or available . Education Likewise, the role of education cannot be overrated in occupational health . However, such education must be based on a broad and profound under- standing of the hospital as a workplace and this comes only from good data collection, efficient health and environmental monitoring and appropriate research . The educational process should begin when employees first join the staff so that they understand the nature (and hazards) of the job. Education should cover appropriate training, a clear ur.derstanding of what to do in an emergency, and the need to refer to the OHS for furthu acvice and help regarding any aspect of health at work. The informed and trained employee is less likely to be injured or to become ill. Of particular importance is the need to help the new employee with the problems and rigours of caring for the sick and the dying. RECOMMEND A TIO NS T'ie Working Group recommended that WHO and its Member States should: give due attention to the hospital environment; study pregnancy outcome and coordinate the collection of inter- national data needed for such investigations; consider the collection, transport and disposal of hospital waste as a matter of some priority; develop studies on the differential infection rates in hospital staff; stimulate research into the causes of absenteeism; 21 reappraise current legislation regarding hospital staff health and enact new regulations, if necessary, while ensuring implementation rather than mere passage of such laws ; give early consideration to the development of occupational health teams to cover all hospitals. REFERENCES I. Ronot, P. et al. Introduction a l'ergonomie de l'equipe soignante. Archives des maladies professionel/es, 32: 749-785 ( I 971 ). 2. Harrington, J.M. Shift work. A critical review of the literature. London, H.M . Stationery Offic.:, 1978. 3. Basic aspects of the safety philosophy of electrical equipment in medical practice. Geneva , International Electrotechnical Commission , 1976 (IEC Publication 513). 4. Solasinski, K. [The effect of electromagnetic field on the work of electromedical instruments] . Szpita/nictwo po/skte, 21: 125-132 ( 1977). 5. Manual on radiation protection in hospitals and general practice. Geneva, World Health Organization, Vol. I, 1974; Vol. 2, 1975; Vol. 3, 1975. 6. Spence, A.A. & Knill-Jones. R.P. Is there a health hazard in anaesthetic practice? British journal of anaesthetics. 50: 713-719 ( 1978). 7. Falck, K. et al. Mutagenicity in urine of nurses handling cytostatic drugs. Lancet, I: 1250-1251 ( 1979). 8. Use of ethylene oxide as a sterilant in medical facilities. Special occu- pational hazard review. Washington. DC, National Institute for Occu- pational Safety and Health, 1977. 9. Court-Brown, W.M. & Doll, R. Expectation of life and mortality from cancer among British radiologists. British medie1/journa/, 2: 181-187 ( 1958). 10. Seltser, R. & Sartwell, P.E. The influence of occupational exposure to radiation on the mortality of American radiologi~ts and other medical specialists. American journal of epidemiology, 81 : 2-22 ( 1965). 11 . Lunn, J.A. Hospital hazards. Practitioner, 210: 490-499 ( 1973). 12. WHO Technical Report Series, No. 512, 1973 (Viral hepatitis: report of a WHO Scientific Group). 13 . Harrington, J.M. Health and safety in medical laboratories. Bulletin of the World Health Organization. 60: 9-16 (1982). 22 - ---~----------------------- ---------- 14. Rycroft, R.J.C. Occupational dermatoses in perspective. Lancet, 2: 24-26 ( 1980). 15. Edling, C. Anaesthetic gases as an occupational hazard •- a review. Scandinavian journal of work, environment and health, 6: 85-9 I ( 1980). 16. Formaldehyde - evidence of carcinogenicity . Current intelligence oulletin, 34: 1-15 (1981). 17. Harrington, J.M. The health industry. In: McDonald, J .C., ed. Recent advances in occupational health. London, Churchill Livingstone, 1982, Vol. I, pp. 77-84. 23 Annex I OCCUPATIONAL HAZARDS OF THE HEAL TH PROFESSIONS M. Tolonen° INTRODUCTION The purpose of this report is to review recent developments and current knowledge of occupational hazards in health professions, to predict future research requiremen-,s and to recommend training, information and other control measures in order to reduce or eliminate occupational risks. Health professions generally are not regarded as particularly high-risk vocations - rather the reverse - but information exists to the effect that certain specific conditions in the working environment in hospitals, clini- cal laboratories and e1sewhere have given rise to occupational hazards in certain categories of health profession. Groups at risk, such as those working in bacteriology, radiology, pathology and anaesthesia, should be given higher priority m work safety . Furthermore, many health profes- sions involve physica! and mental stress, as well as long hours of duty, all of which may be categorized as work-related disorders: vascular and cir- culatory conditions, peptic ulcer and mental disturbances . The lifting and handli 1g of geriatric and other invalid patients are generally related to low back problems amongst nurses and nursing aides. Anecdotal detail, rumour and suspicion abound, but facts are few. This holds particularly true as regards new medical technologies, such as com- puterized X-ray examinations, ultrasound nonionizing radiation and the use of many pocent;ally hazardous chemical substances. There is a general and growing awareness of, and concern for, the potential adverse health hazards among health professionals. A careful assessment of current knowledge is therefore required in order to provide pertinent up-to-date information, not only for anxious health professionals, but also for other decision-makers who often greatly influence the training of health personnel, their working environment and other working conditions . While compiling this report, it became evident that the issues are numerous, as are the opinions on any given issue published in the litera- ture. The literature does not reveal the problem as a whole, and does not a Institute of Occupational Health. Helsinki, Finland. 24 permit a reliable evaluation of current trends. Reliable statistics on acci- dents, injuries and illness among health personnel, directly or indirectly related to their occupation, are required . Because of the lack of such data, this report draws heavily on adverse health effects that have been published in the literature and, consequently, accentuates "publishable" effects, i.e. data that have been considered worthwhile publishing. Therefore the problems of nurses, physicians and dentists may receive undue attention as compared with those of other staff. Because of the vast bulk of literature, no attempt has been made at being representative or systematic in references, but rather they are delib- erately selective in order to provide , it is hoped, relevant and useful information for the countries within the European Region. HEAL TH PERSONNEL There has been rapid growth in health manpower, particularly a dramatic increase in the number of physicians, in recent years. In the USSR there are 1 034 000 doctors (not including feldshers) and probably 5 100 000 nurses. The number of physicians, dentists and nurses (including midwives) in proportion to the population on 31 December 1976 in selected countries of the Region is presented in Fig. 1-3. The number of doctors in 1977 in selected countries is given in Table 1. The figures on laboratory technicians , X-ray technicians, dental tech- nicians, physiotherapists and other personnel were not av<' ilable for this report. Be that as it may, health professions today form a considerable labour force, millions of people, within the Region. HEAL TH HAZARDS Injuries and accidents Neither national nor international figures on accidents and injuries amongst health professions were available for this report. This may be because a considerable proportion of injuries among health professionals are not particularly characteristic, or even related to working in health care, yet there are risks of injuries which are specific to health pro- fessions (1,2). 25 Fig. 1. Physicians per 100 000 inhabitants in selected European countries, 1976 USSR Czechoslovakia Hungary Austria Bulgaria Greece Italy Belgium Germany. Federal Republic of Denmark German Democratic Republic Switzerland Spain Norway Sweden (1975) Iceland Scotland Netherlands Poland France Finland Northern I rel and Romania England & Wales (1974) Malta Ireland Luxembourg Albania Turkey ·:·:·:········································:··· :·:·:·:·:·:·:·:·::·:·:·:·:·:·,·:·:·:·:1 337 ·:·,·:·········:···:·:·:·:·:·:···:·:·: ·:··· ··· ···· ·······:·:·········:1 247 :.:::·::::::,·.·.·.·.·.·.·:···:·······:·:·.·.·:·:·:·,·.·.:.·:·. :i 2~7 ,:,::::::::·:·:·:::::·::::::::;·:·::;:::::::;:::,::::·:::·::::] 2~5 :·.,·=::.,::,,,::::::,::,:::::.::::,::,,::::·:·:::::::·:::·:·:~ 22 ::::::-:::::::::::::=:·:::::-:·:::·:-:-:·:·:::::t17 ·:·:;:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·l 152 =::::::,:,:,:,:,::::C::::::::::::,::::::::::d157 ,·,·,,,·,·,·,·,,·,·,,,,::·,,,::::l 165 . ':':':':':':':"':':':':':':':':':':':':"':'~ 162 .•.•.•,•····--· ·························· ] 153 .;.; .:,: •: •:•:•:•:•:• :•:•:•:•:•:•:• :•:• :::! 150 ,,,,,,,,,,,,,=,=,=,=,.,.,.,.,.,.,.,.,.,.,:l 150 t;::::: ::::::::,:,::::::,:.:,:.:. ·.: I 1 3 • :I 1l ' ,,::,'~, :,1 ~::::: ;:;, :: ;;:, ;,;:;::, ·1~= 5-~ 0 ~ I 0 50 100 150 200 250 300 350 Source: Yearbook of the National Board of Health, 1911/78. Helsinki, National Board of Health, 1979. 26 Fig. 2. Dentists per 100 000 inhabitants in selected European countries, 1976 Norway Denmark Sweden (1975) Finland ::::::::::::::::::::::·,:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:1 98 Greece Iceland Switzerland Germany, Federal Republic of France German Democratic Republic Poland Bulgaria Czechoslovakia USSR (1974) Netherlands Scotland Romania Luxembourg Northern I rel and England & Wales Hungary Ireland Yugoslavia Belgium Austria Albania Turkey Spain •.•.···················································'·····························.] 87 ,, ,, ,,,,,,,,,,,,,,,,,,,;,,,:,:,:,;,;,;, :,;,,,,,,,;,;,:,;,;,:,;,:,;,;,;,;,;,;,;,;,;,, TT 86 :.:.:.::·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:··········· ·· ·· ·:1 73 :.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.:.::::::::::::::::::::1 67 :.:.:.:.:.:.:.:.:::.:.:.:::.:::::,:.:::,:,:.:.:.:,:,.:1 57 :.::::(:::::::::·:·,:·:·,,,:·:·:::::::: :] 57 :·:·:·:,::::::::::::::·,,,:·,:·:·:·,:·:·:·,-:1 52 :::::,:,:,:,::::::::::::::::::::::::::':.::::::::: 50 ., ,,,,,,,,,:,:,,,,,:,:,:,:,:,:,:,:,:, :, :,:,:,::.1148 ·: ·:· ··:·:·:·:·:·,:······················.~ ll5 ··········································:.I ll5 .:.:.:.:.:::.:.:.: .:.:::::::::: ::::::::: ~ 4 : ... :.:.:.:.: ....... : ... : .... ·.···•:•:-I 40 ::: ::=:::::::::::::: ::::: _- : .:;I 33 ::.:.:.:.:.:::.:_:::::_:::::::: 1 33 ·:·:·:·:·:·:=:·:·:·:::·::···:1 31 ·:·:·:·:·:·:·:·:·=·:·:·•···•·:a 31 ···························•]30 .,.,.,.,.,.,.,.,.,.,.,.,.J 29 ·=··· ····················:1 28 :·:·:·:·:·:·:·:···(···::l 21 ······::::-:·:·:···,,·· 26 :::::::::::::::::::::::: 25 ..... : .... ·.•··•:! 1~ EB 13 EJ] 13 [I] 10 0 25 50 75 100 Source: Yearbook of the National Board of Health, 1977/78. Helsinki , National Board of Health, 1979. 27 Fig. 3. Total number of nurses, midwives and practical nurses per 100 000 inhabitants in selected European countries, 1976 Finland Norway Sweden ( 1975) Czechoslovakia Denmark Ireland Northern Ireland Iceland (1974) France (1975) Hungary Scotland (1975) Switzerland Bulgaria England & Wales (1974) Poland Germany , Federal Republic of Austr·a Netherlands Yugoslavia Albania (1972) Portugal Romania Spain Greece (1975) ',:,:==,:,:,:,:,:,:,:,=::,:::::::::::,:,:::,:,:,:::,:,:::::::,:::=:=::::::=:=,::::l 874 ==::::':=::::=:::=:==:=:=:::::::::::=::::::=:::'::::=:=:::,:=::::':::::::::::::! 807 :::::::::::::::::::::::::·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·1 731 ·:·:·:·:·:·:· :· :· :· :· :· _. :· :·:: :. •. ·::::::. •. • .• ::i 608 :·==:=:,:=::::::,:,:=:::=::::=:'::=:=:,:=:,:=:=:=::::===:! 592 ,:,:,:,:===:,=,:,:,:,===,==:=:,=,:,:=:=:===:=:,::::=:::l 568 ::::=::::::::::=::::::::::=:=:===:=:=:=:===:=:=:=::::::l 568 ,:,:,:,:,:,:,:·:,:,:,:,:,:,:,:·:,:·::::::::::::::::::] 543 =:':':=:::::=::=:::::::,:,:=:=:=:::::::::::::::::::::i 541 ::=::::=::::::=:,:=:::,:=::::::,::::::=:::,:::=, 489 =:=:::=:=:=:::=::::::::::::::::::::::::::,.,.:~ 482 ::•:·:·:·:·:·:·:·:·:·'·:·:·:·:<·:\·Fl 4 5 ::::::::::::::::::::::::::::·::::::::::::] 4,4 :=:-:-:-:-:•:•:•:•:•=·=·=:=·=:=·=·='~ 375 ·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:·:1 375 :::::::::::::::::::::::::::::::::<I 371 ··································:~ 370 ·······························J 334 ·:·:·,·:·:·:·:::::·:·:·: 257 ;:;:;:;:;:;:;:;:,:j 1 3 ·················:i 1 }3 :,:,:,:,:,:,:,:i 17) ill[] 111 Das 0 250 500 750 1000 Sourr:e: Yearbook of the National Board of Health, 1977/78. Helsinki, National Board of Health, 1979. 28 Table 1. Numbers of phys1c1ans in the countries of the European Community (EC) and the Nordic countries. 1977 Country No of physicians EC countnes 503 000 Belgium 19 B72 Denmark 10600 Fran ce 86 306 Federal Republi c of Germany 1 29 146 Ireland 3 900 Italy 145 000 Luxembourg 400 Netherlands 22 913 United Kingdom 85 000 Nordic counrnes 42000 Denmark 10600 Finland 7 350 Ice land 425 Norway 7 320 Sweden 16 000 Total approx 534 000 I . Hand injuries. Staff in central steril e supplies departments of hospitals suffer unnecessa ry hand injuries beca use equipment returned to them for cleaning and resterili zing often contains sca lpel blades and o ther sharp instruments ( /) . 29 2. Injuries from hypodermic needles usua:ly involve domestic staff and porters handling waste from bins and sacks. In one year, over 250 such workers were injured in one large British regional hospital (]) . Prevention of such injuries also lowers the risk of hepatitis B infection. 3. Falls and back injuries often involve domestic and nursing staff. In hospitals many floor surfaces remain wet and potentially dangerous . Lift- ing and handling patients, as well as bedmaking, expose nursing staff to the risk of back injuries although these are not quite as common as might be expected ( 1). 4. Lack of personal safety equipment. Maintenance staff are prob- ably as liable to injuries as they would be in any circumstances. The unnecessarily high number of hand and foot injuries , in particular in handling heavy gas cylinders, has been attributed to negligence ( /). 5. Assaults by patients. Most accidents are causec' by either an unsafe action (by a person) , or by an unsafe condition (the environment) , or the combination of the two. Some typically hazardous actions are (3): (a) operating equipment without authority; (b) failure to take precaution against unexpected movement; ( c) operating/working at an unsafe speed; (d) failure to give warning or signal danger; (e) removing (or disconnecting) safety devices; (/) using defective tools or equipment; (g) unsafe use of tools or equipment; (h) adopting a dangerous position or posture; (i) servicing or moving (energized, or otherwise) hazardous equipment; (j) riding hazardous moving equipment; (k) horseplay, distracting, startling, etc.; (/) failure to wear personal protective equipment or wearing improper garments, including jewellery, etc. 30 More important than actual unsafe conduct in itself are the reasons for it, which can be grouped into three broad categories . I. Lack of knowledge or skill . 2. Conflicting motivations and attitudes. 3. Physical or mental inadequacies. Accident prevention in the health professions should follow the mod- ern principles and guidelines in industry and business with advanced control programmes. Ergonomic problems Excepting dental practice, only a few reports on ergonomics in health professions were found in the literature. In a study ( 4) on the relation between low back pain and occupation the earliest age of onset of low back pain occurred among bank clerks , in heavy industry, farming and nursing. In hospitals the characteristic ergonomic problems seem to be the handling and lifting of patients, and bedmaking, all associating with low back pain among nurses and nursing aides (5). Ferguson (6) reported a 4% annual incidence of strain injuries associated with manual patient handling in three Australian hospitals with a total of 14 189 employees. Strain injuries were by far the greatest contributor to time lost from accidents , and lifting of the patient was the most commonly reported cause of injury. Geriatric nursing associates suffer a high frequency and recurrence of low back pain . Nursing aides with low back pain consider that their work puts particular stress on the spine ( 7) . The arduousness of bedmaking in hospitals has been demonstrated, e.g. by means of pulse count measured telemetrically (8). Adjustable beds and training in bedmaking have been recommended. According to Karvonen et al. (9) , lumbar exercise and correct lifting technique have some preventive effect, but without regular exercise only correct lifting remains effective. In contrast, Dehlin et al. (7) found no relationship between different lifting techniques and incidence of low back pain among nursing aides . Back injuries also occur in assisting paraplegic and burn patients in and out of baths . Special apparatuses have been designed to prevent such injuries and to reduce the risk of cross-infection (JO). Commercial bath units and other transporters are available. In dental practice, ergonomics have slowly improved since the 1920s ( 1 I) . At that time the dental treament unit consisted of a chair fixed to the floor , the spittoon on the left of the chair, the bracket table on a 31 hinged arm, and an electric motor to elevate the chair. Syringes were introduced to supply cold water, warm air and warm-water spray. The chair usually faced the window to make the best use of natural light. An additional light source was a cluster of lamps, or an anglepoise. Dentists also began employing an assistant to help with materials, equipment, clerical work and so on. The dental mirror enabled the dentist to work on upper teeth in a more upright position. In the late 1950s the layout and the operating methods in dentistry began to change. High-speed dental turbines were introduced. illumi- nation was improved and a reclining chair was developed, allowing the dentist to sit while operating. Today, the assistant also works seated, making four-handed low-seated der tis try possible . Syringes have also been redesigned and auxiliary personnel have been trained to carry out various form s of treatment under the dentist's supervision . Since the mid I 960s the average age of dentists has dropped appreci- ably(/ 2-14), following the opening of new dental schools and the increase in the number of dental students. Fewer dentists are now in individual practice, more are in partnerships or are assistants or associates, in both the private and public sectors. Practitioners now work fewer and shorter hours than previously, e.g. older dentists in South Wales had reduced their working week by nearly 5 hours during the period 1965 to 1974 (12) . The British periodic national surveys show a steady reduction of 11 % in the hours worked per year by principals in the general dental services between 1963 and 1973 (12), yet dentists see more patients per unit time than before because of improvements in working methods. Obviously the dentist's workload has declined over the years ( 12), with the total energy expendi- ture being about 3000 kcal ( 15), and consequently fewer dentists report fatigue from work (12, 16). The low-seated operating position is generally recommended for use when working on reclining patients. In 1974, 66% of British dentists worked seated for half of the time or more ( 14). Older dentists seem as willing as their younger colleagues to change their operating positions. In 1977 more than half of the dentists in South Wales worked low-seated, one fifth used a high stool and another fifth did not use any kind of stool at all (12). In 1974, 99% of Stockholm's dentists still used vertical patient chairs (16). Neck and low back pain might be attributable to low-seated operating (12). Considerable changes have taken place in the type of unit used. Most dentists now use a mobile unit, though the fixed unit on the left side of the chair is still a popular arrangement. Modernization of the unit seems not to be confined to younger dentists. The current concept of dental office design includes pleasant surroundings, soft pastel colours, comfortable furniture and relaxing music. The ultra-high-speed handpiece and contra- angle handpiece permit vibration-free cutting of the tooth. 32 Older dentists are likely to show more job satisfaction than the middle- aged and younger ( I 2). American dentists seem to express more job satis- faction than dentists in South Wales ( I 2). Personal aspects of service seem to be important to dentists . Recommendations for optimum operating positions ( I 7-22) have been obtained from postal surveys and from numerous ergonomic appraisals of the dentist working either alone, with one or two assistants, or on patient simulators. Furthermore, efficiency and physiology have been studied intensively, yet these studies are hampered by the relatively low total workload and the difficulty in objectively assessing potential adverse health effects of working postures in dental operations. For instance, according to Kajland (16), in 1974 the public health service dentists in Stockholm had, on average, a shorter work week and a lower overtime rate than clerks employed by the city of Stockholm. The dentists themselves also reported a lighter workload than the control group: musculoskeletal troubles , skin disorders and haemorrhoids, however , occurred more fre- quently among the dentists . In particular, trouble in the right shoulder and the back were more frequent among denti sts than controls. Disorders in the right hand and shoulder were mainly reported as dull aching pains when moving , and tenderness, particularly in older subjects. Most dentists spend their working hours at the o perating chair, 99% using vertical chairs. Unanimous ergonomic assessment of dentists' working postures was difficult even when their working positions and movement patterns were filmed and screened in front of a panel of experts in ergonomics, physical therapy and odontology (16). However, younger male dentists are judged to have the best working postures while older females have the poorest. Bad posture is possibly associated with the subjective troubles. Thus the working posture depends both on the individual and on environmental factors. A dentist's stationary work evidently creates a problem of hypo- kinesia (16) . It should be compensated for through leisure time activity. Health professionals are encouraged to bring up principles and appli- cations of ergonomics not only with respect to their own present work but also whenever new workplaces or layouts are planned or whenever tools and equipment are designed. Optimal ergonomic design ensures maximum effidiency of operation, minimizes the possibilities of human error, elim- inates risk of injury and prevents fatigue. Physical hazards Physical hazards to be considered as potential occupational risks for health professions include ionizing radiation, nonionizing radiation, elec- tricity, illumination and noise. 33 By far the most important of these hazards is ionizing radiation which has received much attention in international literature. National auth- orities (23) and the International Labour Organisation (ILO), the Inter- national Atomic Energy Agency, the International Commission on Radi- ation Protection (ICRP) (24) and the World Health Organization all have a long-standing interest in protection of both the general public and radiation workers. WHO has recently issued a manual on radiation protection in hospitals, general practice and dental practice (25-28). Much of the fundamental information covered here draws on the publications ofICRP, but the WHO manual may be more appropriate for a reader with a medical background . "Maximum permissible dose" (MPD) is defined by ICRP as follows: The permissible dose for an individual is that dose, accumulated over a long period of time or resulting from a si ngle exposure, which in the light of present knowledge carries a negligible probabilit y of severe somatic or genetic injuries; furthermore, it is a dose such that any effects that ensue more frequently are limited to those of a minor nature that would not be considered unacceptable by the exposed individual and by competent medical authorities. For whole-body exposure of radiation workers the MPD is 5 rem per year averaged out over the working life (from 18 years of age). The current MPD and dose limits are presented in Table 2. Individual monitoring is recommended for workers who are exposed to radiation under such conditions that the resulting doses might exceed three tenths of the annual maximum permissible doses. For other workers, individual monitoring is not required, environmental monitoring usually being sufficient. Overexposu re to radiation may induce radiodermatitis (29.30), chromo- somal changes (31), cataract and haematological di sorders, including leu- kaemia (25). The literature available for this report did not , fortunately , reveal any radiation injuries from the 1970s, yet pre-employment medical examination and periodic health surveillance are still an important part of the whole radiation protection programme. For fuller information the reader is referred to the WHO manual (25-28). Nonionizing radiation, extensively used in physiotherapy and laser surgery, also requires protection of health personnel in the form of infor- mation about the potential hazard and proper working modalities. Ill health attributable to nonionizing radiation was not found in the literature researched for this report. For further information, e.g. on safety mea- sures, the reader is referred to the WHO publication Nonionizing radiation protection (32). Safety in the use of electromedical equipment has been outlined in a number of national and international standards and recommendations (33- 52). Special reference is made to Publication 513 by the International 34 Table 2 . Maximum permissible doses and limits set by the International Commission on Radiological Protection . 1 966 Maximum dose Organ or tissue Adult radiation staff M embers of the publi c Gonads. red bone marrow Skin . bone Thyroid Extrem1t1es Other single organs 5 rem / year8 30 rem / year 30 rem /yea r 75 rem / year 1 5 rem / year 0 . 5 rem / year 3 .0 rem / year 3 .0 rem / yearb 7 . 5 rem / year 1 . 5 rem / year a For pregnant women the dose to the fetus accumulated during the remarnmg period of pregnancy after the diagnosis should not exceed 1 rem b 1 5 rem / year to the thyroids of children up to 16 years of age Electrotechnical Commission (37) which outlines the measures to safe- guard the patient and operator during the use of electrical equipment in medical practice. The report considers the following: electricity, radiation, ultrasound, mechanical hazards, excessive temperature, fire, harmful liquids and gases, and component or power breakdown. The measures indicated concern safety of equipment, in particular electrical safety, safe instal- lation (assembly of all wiring, switches, transformers and other parts intended to supply power to electrical equipment) and the "application code" for safe use of equipment. Also, a recent series of articles (52) discusses the various aspects of electrical hazards and their prevention. Illumination, particularly in the operating room, merits consideration as both poor and excessive illumination in the surgeon's field of vision (and for others who perform visual tasks) may present a hazard (53) . The relationship between general and specific lighting is assuming greater importance in the prevention of fatigue and in the elimination of some of the disability that may arise from glare. Fibre-optic supplemental illumi- nation has been suggested, though it entails certain problems of instability of equipment and possibly excessive delivery oflight which is transformed into heat in the tissues (53). Noise exposure that would eventually damage hearing is rare in health occupations, although dental personnel's exposure to noise merits closer inspection . 35 High-speed dental turbines (200 000 to 400 000 rev/min) have their maximum energy in the frequency range around 8000 Hz (54), and some drills around 4000 Hz (55). The noise levels at a distance of 30 cm from the drill or the suction-tube placed inside a patient's mouth vary between 80 and 90 dB (54-57). In one study (56) only a third of the sound frequency spectrum fell between the limits of 1000 and 2000 Hz, i.e . the band con- sidered most damaging to hearing. Another third was between IO 000 and 20 000 Hz, frequencies relatively harmless to hearing, and the last third occupied the intermediate frequency band . In one study audiometric examinations yielded results indicating audi- tory microtraumas (a hearing loss of 35 dB at 8000 Hz) (58). Another study showed slight hearing impairment (59) and yet another revealed nothing significant (60). Some authors have warned that the whine of high-speed dental drills may cause a more serious damage from continued ex- posure (57,58), while others see no urgent reasons for recommending hearing protection in dental practice (54,56) . Exposure to noise produced by high-speed drills in the dental pro- fession involves only a fraction of the working hours (in one study an average of only 6 minutes per working hour (55)) . When the available noise measurement values are related to the total of exposure hours and the intervals free from noise in dental practice, the risk of noise-induced hearing impairment among dental personnel seems rather hypothetical. Chemical substances A vast number of chemical agents are used, particularly in medical labora- tories, and chronic, intermittent or occasional exposure to potentially harmful substances may present a health hazard. From a health viewpoint, the chemical agents may be classified, for example, as irritant, toxic, allergenic and carcinogenic. In the present context the volatile anaesthetics occupy the most important role. Volatile anaesthetics Today the following volatile anaesthetics are generally used (61,62): di- ethyl ether, introduced in 1842; nitrous oxide ( 1844); cyclopropane ( 1933); trichloroethylene (I 934); halothane ( I 956); methoxyf1urane (1960); and enf1urane ( I 974). Isof1uorane is also used experimentally. Anaesthetic gases may be present, not only in the operating theatre but also in anaesthesia induction rooms, recovery rooms, delivery rooms and dental surgeries (61-66) . 36 Extremely high concentrations of volatile anaesthetics have been measured in badly ventilated operating-theatres without appropriate con- trol measures, e.g. 20-500 ppm of ether and diethyl ether during open administration (67), 1500-3000ppm (68), 7000 or even 14600ppm of nitrous oxide (69), up to 290ppm of halothane (70) and about 300ppm cyclopropane (69) . Even in mechanically-ventilated modern operating- theatres, unless additional measures are taken to reduce waste anaesthetic gases, the levels of nitrous oxide reach hundreds of ppm (23,63,69), those of halothane tens of ppm (68, 70, 71) and those of methoxyflurane in deliv- ery rooms 0.5-0.8 ppm ( 72). According to a recent study (65), dentists in a Danish child health service inhaled over 1000 ppm of nitrous oxide for about 40 minutes daily; a scavenging system reduced the time-weighted average concentrations by 90-98%. Moreover, these may be "hot spots", i.e. places where the concen- tration of gases is greater than expected, depending on the air flow patterns in the operating-rooms, on the air flow volume and on eddies (73) . The waste gas concentrations depend 0.1 a variety of factors such as method and technique of anaesthesia, and specific precautions taken in order to reduce the concentration . Acute effects and experimental studies have been recently reviewed by Siddons & Lauwerys (61). In this report only long-term effects of modern anaesthetics will be considered. It has been argued that the triad of spon- taneous abortion, congenital abnormality and infertility might have resulted from an increased occurrence of fetal abnormality, possibly due to occupational exposure to anaesthetics (61,62). The Ad Hoc Committee report (74) of the American Society of Anas- thesiologists (ASA) on the effect of trace anaesthetics on the health of personnel reviewed the literature up to 1974 and concluded that women were subject to excessive risk of spontaneous abortion and congenital abnormalities in their offspring, as well as cancer and hepatic and renal disease. Studies published on the topic have suggested increased abortion rates in male anaesthetists' wives and for dentists ( 75), premature births ( 76), shorter average term of pregnancy in cases of miscarriage ( 77), a change in sex ratio of live-born babies ( 76, 78), cancer ( 74) particularly in lymphoid tissues and leukaemia ( 66,79), hepatic ( 71,74) and renal disease ( 74), de- terioration of mental functions (80), and other psychological disorders such as headache, fatigue and irritability (81). Many of the studies pub- lished on the subject are taken from postal inquiries and many of them suffer from obvious shortcomings such as lack of proper control material, low response rates, materials too small to be conclusive, lack of control of confounding factors and other flaws rendering conclusions from the data difficult. A recent Swedish study (82) has evidenced a slight reaction (within the range of normal values) in the delivery room personnel's blood 37 urea nitrogen, serum uric acid, S-ALA T and S-ASA T. They had been exposed to 0.5-0.8 ppm of methoxyflurane and to 300-480 ppm of nitrous oxide. As reviewed by Siddons & Lauwerys (61), out of the many sus- pected serious outcomes, only an increased rate of spontaneous abortion has been cogently linked with employment in operating theatres . Indeed, there is epidemiological proof beyond all reasonable doubt that employment in anaesthetics is associated with some deleterious effects on the reproductive systems offemale workers, chiefly an increased rate of spontaneous abortion but also birth of underweight children (61,62,83). Some anaesthetics , e.g. methoxyflurane , are polyhalogenated ethers and their structural similarity to recognized carcinogens , such as bis- chloromethylether, bis-chloroethylether and chloroether have been a mat- ter of concern (84). In fact , experimental evidence exists showing that all major inhalation anaesthetics are teratogenic (85,86) and that chloro- form (87) , trichloroethylene (88) , fluoroxene (89) and halothane (90) are mutagenic or carcinogenic, or both . Moreover , nitrous oxide and halo- thane synergistically produce an increased number of cells with abnormal nuclei , in both mitosis and interphase in Chinese hamster fibroblasts (91). It should be borne in mind , however , that in experimental studies higher gas concentrations have been used than those reported in pollution studies of operating theatres but, on the other hand , no finite lower limit of anaesthetic gas exposure has been established below which these effects are unlikely to occur. Experimental and epidemiological data naturally have raised the ques- tion whether work in anaesthetics causes congenital anomalies, failure to thrive and cancer, since mutagenicity, teratogenicity, birth defects and carcinogenicity are all known to be linked in that any mutagenic agent is likely to produce cancer. Anxiety may have been caused by reports on cases of congenital abnormalities in the musculoskeletal or nervous sys- tems in children of anaesthetists (92, 93) and by the recent observation that the urine of anaesthetic nurses is mutagenic (94) . According to Rosen- berg & Kallio, however, there are no morphologic changes in the chromo- somes of nurse-anaesthetists (95). For fundamental data , the reader is referred to a monograph published by the International Agency for Research on Cancer (96) . So far , two collaborative national studies on cancer and congenital abnormalities have been published, one from the United States (74) and the other from the United Kingdom (97,98). The USA data suggested a possible relationship between maternal occupational exposure to volatile anaesthetics and congenital abnormalities, while the United Kingdom study showed only a possible increase in reporting minor congenital abnormalities. A 10% sample of the United Kingdom material referred to above (93) again gave results diverging from those gathered from all 38 United Kingdom anaesthetists studied. The reasons for the differing results and opinions are not yet fully understood. One of the investigators (84) seems to believe strongly that chronic exposure to low concentrations of volatile anaesthetics has caused the adverse effects which have been published and he even made attempts to incriminate inhalation of anaesthetic agents, in particular halothane (99), fearing another thalidomide disaster (84). OtheVi suggest reduction or prevention of operating theatre contamination (83, 97, 98.100) though they still see no evidence to support or allay anxiety among anaesthesia personnel. From an occupational health point of view, demonstration of waste gas in the ambient air, in the expired air, blood (10/-/03) or urine (/03) of anaesthetic personnel justify, even without strong epidemiological evi- dence, demands for reduction of the present concentrations of anaesthetic gases. The following measures are generally recommended to reduce occu- pational exposure to volatile anaesthetics (JOO. 104-109): the use of closed systems of anaesthesia; tubing the gases on the floor by using a directional nozzle on the Heidbrink valve for reducing the anaesthetist's exposure, though the effect on the general concentration is slight ; switching a char- coal canister into the closed system for adsorption of the gases toward the end of the anaesthesia; avoidance of high gas flows with massive spillover into the operating theatre; adequate ventilation of the anaesthesia rooms; use of antipollution devices especially designed for anaesthesia; and scav- enging of waste gases which ensures the greatest reduction of the atmos- pheric gas concentrations, up to 90% for halothane and 85-98% for nitrous oxide. Studies on general and spot concentrations have clearly shown that the eventual hazards are amenable to correction and that simple and effective precautions are readily accepted. The Swedish National Board of Labour Protection in I 974 issued a guide ( 110) and the Council of the Association of Anaesthetists of Great Britain and Ireland in 1975 (/ //) issued recommendations for the re- duction of pollution in operating theatres . Hexachlorophene Her.achlorophene - an antimicrobial agent - has been on the market since the I 940s, but it was only in the early I 970s that repeated use of this drug and other antibacterials led to significant levels of the chemicals in the users' blood. Hexachlorophene was associated with neuropathy in animal studies and similar blood levels were found in humans using the drug topically. In addition, French reports showed that infants accidentally exposed to 6% hexachlorophene in talcum powder suffered brain dam- age (/ / 2). The Food and Drug Administration (FDA) in I 972 banned all 39 nonprescription uses of the drug, restricting hexachlorophene to use as a surgical scrub and hand-wash product for health care personnel. New concerns have arisen about the safety of hexachlorophene . Hal- ling ( 113) reported serious human birth defects associated with topical use of hexachlorophene in Swedish hospitals . The teratogenetic effect of topi- cal use of the detergent has been disputed (113-115) ; for instance, the National Board of Ht:alth in Sweden has expressed serious reservations about the study because of its technical deficiencies (112). A large-scale study has been planned involving the pregnancy outcome of some 30000 women working in Swedish hospitals during 1973-1975. Prelimi- nary results reportedly show no evidence of an increased incidence of birth defects (114) . The Food a'1d Drug Administration (FDA), however , in 1978 published an in ~erim warning against the use of hexachlorophene during pregnancy (1 ! 2). The FD A's concern stems not only from the Swedish studies but also from animal research . Because of the propensity of the substance to be absorbed, it has been associated with brain lesions in rats, rhesus monkeys and newborn babies receiving topical applications. The Administration stated that present research in the published literature failed to provide assurance that hexachlorophene is safe for use by women who are or could become pregnant. Formalin Hypersensitivity to formalin used to sterilize artificial kidney machines has been shown by inhalation provocation tests in nursing staff (116) . For- malin asthma has not been reported elsewhere in the staff of renal haemoly- sis units and there are only two reports on formalin-induced respiratory disease in workers in laboratories where formalin is widely used ( I 17, 1 I 8). Mercury The use of mercuric chloride as a histological fixative has been associated with high atmospheric concentrations of mercury vapours (up to 0.5 nmol/1) as well as mercury compounds (119) . This may present a potential occupational health hazard unless routine control measures, ventilation and careful handling of mercuric chloride solutions are applied. The ubiquitous use of mercury in the preparation of restorative amal- gams constitutes a potential hazard to dental workers (120) . Merfield and co-workers in 1976 reported 4 cases of mercury poisoning in dental sur- geons and assistants following spillage of 250 g mercury ( I 21). Even a fatal intoxication in a dental assistant was eventually reported (122). 40 Measurements of airborne mercury vapours and particulate mercury have shown exposures in dental surgeries occasionally exceeding the TL V of0.05 mg/m 3 ( 123-128). However, significant differences in atmospheric contamination have been found between laboratories, sites of measure- ment and times of day, correlated with mercury consumption, number of amalgams per day, age of laboratories, thickness of carpeting and fre- quency of cleaning. The atmospheric mercury concentration also appears to be greatly dependent on the dentist's working technique, in particular during removal of old amalgam restorations (123) . Mercury vapour is probably liberated from the finely divided amalgam by the heat generated during drilling. The averagP. time taken for the removal oi old amalgam restorations is about 2 minutes. An average concentration of0.4 mg/m 3 of vapour for removal of 10 a .11alga:n restorations, 2 minutes each, would equal the dose that could be absorbed at a concentration of0.02 mg/ m3 in 6 hours' exposure. However, the greatest potential hazard may result from contamination of the hand wher. working with mercury metal or fresh amalgam. Mercury concentrations in head and body hair, finger and toe nails of dentists and their assistants have exceeded those of persons without occu- pational mercury exposure ( 126). Analysis of mercury concentrations indicates an absorption of mercury by dental workers (129) , yet the results for individt•als cannot be corre- lated with severity of exposure nor with the incidence of symptoms of intoxication. Urinary mercury concentrations in the same individual vary considerably at different times. Generally, a urinary concentration of 0.05 mg/ I is taken as a sign of occupational exposure; persons known not to be exposed rarely excrete more than 0.0 I mg/ I. For instance , the highest concentration recorded by Buchwald was 0.03 mg/ I (123) . Cross et al. (130) in I 978 showed that mercury vapour inhaled was par, ially con- verted to methyl mercury in the body. The differences beiween a group of dentists and a control group were highly significant for total mercury, methyl mercury and the ratio of methyl mercury to mercury in the blood . The total mercury (ng/ g dry weight) ranged from 67 to 518 (mean 227 , median 213) among 11 dentists versus 100-154 (mean 129, median 130) among 17 controls. The respective figures for methyl mercury were: range 8.5-69.5 , mean 27.0 and median 24.7 for dentists versus 1.9-13.7 , 5.7, and 4.7 for the controls; and the figures for methyl mercury(% of total) ranged from 4.7 to 50.4 (mean 4.8, median 12.1) in dentists versus 1.2-9.0 (mean 4.5, median 3.5) in controls. Thus the risks of chronic "mercurialism" in dental workers exposed to mercury vapours may be attributed to methyl mercury. This observation is of special interest since methyl mercury is fat-soluble and has a particular affinity to brain tissue. No clinical impli- cations of these figures have been presented. 41 Brooks & Allingham ( 131) in 1974, after having surveyed 25 dental surgeries in New Zealand , concluded that no mercury hazard was evident but that the potential hazard was there and that che nsk appeared to be greater for assistants than for dentists. Moreover, the awareness of care in handling mercury correlated inversely with personal mercury levels . Wirz & Castagnola l I32) surveyed 32 Swiss dental surgeries in 1977 for their airborne mercury. The author~ concluded that mercury is not an actual hazard for dental personne: if proper safety practice is applied. Airborne mercury levels can be reduc.:d substantially (about 80%), i.e. to a non-hazardous level, by using a water spray turbine drill and by replace- ment of carpet by smooth surfaces and installation of a fume cupboard. In summary, mercury constitutes an obvious potential health hazard in dentistry, in particular during the preparation of amalgam and its inser- tion. Attention is drawn to the periodicity of exposure, the ease and simplicity in monitoring the external and internal environment, and to working methods of mercury expuhion i 1 amalgam preparation . Training in handling mercury and instruction on its toxicity should be given before handling the metal. Installation of a fume cupboard has also been recom- mended in all surgeries where m~rcury is handled. Routine biological monitoring, i.e. blood or urine mercury determinations, seem unnecess- ary, provided that the preventive measures referred to above are carried out. Other metals Certain technicians and denta! mechanics specialize in manufacturing metallic prostheses in a hard alloy consisting of chromium, cobalt and molybdenum, which may also contain up to 2% beryllium (/33). While these prostheses are being ground with small abrasive discs a fine dust is released which may be inhaled. Hogonnaud & Lob published 5 cases of possible hard metal pneumoconiosis among 25 technicians(/ 34). Berylli- osis seemed unlikely but the authors feared a defin:te hazard and suggested the use of alloys free from beryllium. Also, with proper local exhaust ventilation, non precious beryllium-containing alloys may be used safely in dental laboratories (135). Plastics Esters of acrylic acid, in particular methyl methacrylate, fo:m non- breakable glass-like materials and in dentistry the monomers are used to prepare dentures and a variety of filling and coating materials. Surgeons utilize the monomers to prepare a cement which nelps anchor prosthetic devices to bone. Special types of acrylic monomer such as the cyano 42 derivatives are employed as adhesive materials. Most of the acrylic acid esters are volatile substances and can produce nausea (/ 36) and other adverse effects if inhaled ( 137). NION, the Scandinavian Institute of Dental Materials, has conducted research or, air quality in dental laboratories . A Norwegian study revealed considerable concentrations of gypsum dust , porcelain , acrylate, gold and other dusts . Ethylene oxide Ethylene oxide is extensively used in hospitals for sterilizing heat-sensitive equipment. NIOSH in 1977 published a review (138) on occupational hazards with control recommendations for the use of ethylene oxide as a sterilant in medical facilities. The review included results of NIOSH field studies conducted in hospitals. The report recommends a ceiling occu- pational exposure limit of I 35 mg/ m3 (75 cm 3 / m3) over a 15 minute sam- pling period, and a time-weighted average TL V of 90 mg/m 3 (50 cm 3 / m 3) over a given workday. Skin disorders Medicines may induce toxic and allergic dermatitis in health personnel. In addition to drugs , trioxymeth:;lene , amalgam and acrylic pol ymers may cause allergic reactions in dental personnel (139). Excess ski n infections, slow-healing sores and chapping have also been reported in dentists (16) . In a recent German survey ( 140) the most frequent causes of occupational dermatitis among dentists and their assistant~ were disinfectants, deter- gents, plastics and silica paste. Communicable diseases Health professionals are liable t '.l come in contact with patients carrying communicable diseases (/4/). Tuberculosis is a prescribed disease for hospital staff in many countries ( 142). Pathologists and laboratory personnel as a group are exposed to an increased risk of infection (143-153) . A number of manuals and articles have been published on rnfety in medical and pathology laboratories. Among the hazards are tuberculosis , salmonellosis, shigellosis and other bacterial and viral infections, parasitic diseases , viral zoonoses and fungal infections. Surveys on laboratory safety have revealed insufficient safety control, e.g. in I 977 mouth pipetting was still practised in 65% of English and Welsh laboratories and the use of protective clothing was rarely compul- sory ( / 5 /). Also, the servicing of safety cabinets was often inadequate. In 43 view of the wide variation in standards among laboratories, codes of practice have been required rather than relying merely on recommen- dations emphasizing proper hygiene, including specially designed safety cabinets (151) and education and va<.:cination of personnel. Viral hepatitis B (HBV) presents the greatest hazard and therefore it merits closer consideration. HBV risk Hospital medical and ancillary staff run a risk of contracting clinical hepatitis infection some 3-6 times higher than normal (154). The occur- rence of HBV in the: general population exhibits marked geographical and ethnic differences and therefore the actual risk for health personnel varies greatly according to their clientele. All over the world HBsAg has been detected more f,equently in males than in females and in urban than in rural communities . The prevalence of both HBsAg and anti-HBs is highest in young age groups (5-19 ye,rs of age) . WHO (154) in 1972 reported prevalence rates of 0. 1-0.6% in the United States and western Europe, 5-20% in tropical Africa, South Asia and the Far East. In Athens the HBsAg carrier ra:e is.4% and the HBV infection rate is among the highest in Europe (over 25%), anti-HBs being present in 15% of the popula- tion ( 155). In recent years a change has been seen in the epidemiology of hepatitis B and in the HBsAg subtype distribution (156). As increasing numbers of antigen-positive patients are served by medical workers, the likelihood of contact with hepatitis B virus will increase. The highest risk of infection by hepatitis B surface antigen is in occu- pational categories with the greatest exposure to blood. In contrast, direct contact with hepatitis patients does not correlate with serological evidence of hepatitis B infection (157) . Hepatitis contracted from the use of illicit d1 ugs is nearly always associated with subtype ay. This subtype is becom- ing more frequent in western and northern Europe, in particular among new carriers . In 1948 hepatitis was acknowledged for the first time as an occu- pational disease of medical staff by the New York State Workmen's Compensation Board (158). Since then there have been sporadic reports, mainly from the USA, of clinical l:epatitis apparently acquired by labora- tory staff from blood samples (159-161). Until recently , hepatitis B has ber:n rife in some dialysis units in the United States and Europe (162,163). In 1972-73 the prevalence of HB~Ag in 15 centres in the United States was I 7% of almost 600 patients (164) . In I 973 the respective rate for 16 000 European patients was I 8%. In over 20 units in the United States during mid-1972 to 1974 clinical hepa- titis B or symptomless HBsAg developed in 24% of the patients who had no infection at entry, and who remained in the unit for a year. The attack 44 rate for staff was 11 %. In European units in 1973, out of 11 000 patients 10% had acquired HBsAg previously and an additional 10% acquired the antigen during that year (164). Rates for staff are not available. The literature research for this report did not reveal the whole picture of HBV as an occupational hazard in the European Region, but the following data gathered from the literature help to quantify the risk observed in some countries. Bulgaria. In a survey (165) of 32 persons engaged in the production unit at the Research Institute of Haematology and Blood Transfusion, 8 (25%) had contracted viral hepatitis. In the Regional Blood Transfusion Station 4 out of 15 staff members became infected and , in addition , 3 out of 23 members of a surgery ward staff had had HBV. During 10 years 5 members (out of 36) of a laboratory for fractionation of human blood proteins had been infected. Another survey (/66) of 2544 medical personnel in 15 medical insti- tutions in Sofia and the surrounding region indicated a rate of 2.52%, i.e. at least twice as high a risk as compared witn the population at large ( 1.25%). Canada. In 1975 the prevalence of HBsAg among the staff members of a university hospital in Toronto was 13.4% out of 426 persons tested (167). Laboratory staff had the highest rate , followed by nurses . Clerical staff working in laboratories had a rate similar to general duty nurses . Staff with anti-HBs had a 19.3% incidence of hepatitis compared with staff without anti-HBs (7.9%) and 25.6% of the staff with anti-HBs had a history of hepatitis. Denmark. A 5-year survey during 1968-73 in 59 laboratories covered 90% of the personnel in the clinical chemical labora~ories (168). Viral hepatitis was the most common and the only serious disease reported. The disease was reported in 30 workers from 13 laboratories , the annual inci- dence being 2.3 per 1000 employees (seven times that in the general population). Finland. HBV seems to present a minor occupational health problem. During the period 1975-1978 only 10 cases were recorded at the national Occupational Disease Register. Staff of the Finnish Red Cross Blood Transfusion Service, which has provided the entire blood service in the country for 30 years, have never experienced a case of occupational viral hepatitis B (Nevanlinna, personal communication, 1979). The low preva- lence in Finland compared to other countries is not fully understood. (The 45 annual incidence rate of hepatitis is about I 00 cases for the whole popu- lation; the prevalence of HBsAg-positive persons is 0. 16% (169) .) France. Viral hepatitis affecting health care professions has been compensated for as an occupational disease since 1967 ( 170). In particular, staff members of haemolysis centres are at risk. A study (171) of 12000 hospitalstaffin Lyon in 1971 revealed38 casesofHBV,i .e. 0.31 %. An epidemic situation wa found in the nephrology service. Another survey in I 975 (172) revealed 82 cases of viral hepatitis among physicians and nurses of a hospital in Lyon. In the non-university hospital staff from 1970 to 1974 the most frequent infectious disease was viral hepatitis, affecting 6.5% of the personnel (173), and nationwide it accounts for 11.6% of occupational diseases ( 174). In I 976, 746 cases occurred among health personnel, 4 of which were fatal (Pardon, personal communi- cation , I 979) . German Democratic Republic. Hepatitis infection dominates among occupational infections (175,176). Renger et al. (177) found anti-HB in 2.6% out of 5273 medical personnel; the HBsAg was 3.3 times as frequent in the same group. In medical staff the highest prevalences of anti-HB were found in dialysis personnel. These antibody carriers are particularly suit- able for working where there is a risk of infection . The authors suggested a periodic check on medical staff every 3 months for the presence of HBsAg and anti-HB. Federal Republic of Germany. The incidence of viral hepatitis among health personnel has increased by 80% since I 960, a rise not seen in the general population (178). b I 976-1978 there were about 2200 clinical hepatiti cases recorded as occupational diseases among medical staff, about 1850 in hospitals and 350 in ambulatory outpatient health care (Wagner, personal communication , I 979). Anti-HBs is much more common in hospital staff than in the popula- tion at large (179) . Janzen et al. (180) reported prevalences of 2.2% for HBsAg and I 1.7% for anti-HBs among 3770 employees of the Medical School of Hannover. Physicians ( I 8.2%), nurses (20. I%) and members of the cleaning service (26.3%) had the highest frequencies of HBsAg or anti-HBs. Prevalences of HBsAg or anti-HBs were highest in persons associated with dialysis (31.3%), anaesthesiology (31.0%), ophthalmol- ogy (29.4%), neurosurgery (28.0%) and surgery (24.4%). At Frei burg University Hospital during I 968 and I 969 the medical staff showed an incidence of HBV of 0.8%, i.e. a rate 16 times higher than that in the general population (181). 46 Israel. Among Israeli hospital staff 1.8% have been found (/82) to carry HBsAg and 23.9% the antibody. In contrast 0.5% of kibbutz person- nel were antigen-positive and 11 .8% carried anti-HBs. The highest rates of antibody have been found among people born in Middle Eastern countries outside Israel. Netherlands. In a Dutch study (183) a total of 6.2% out of 768 em- ployees in St Radhoud Hospital (including laboratory workers) were positive for HBsAg or anti-HBs or both . Personnel coming into contact with blood from patients of the renal unit showed a positive hepatitis serology rate of 18%. The true incidence is probably even higher than detected by present methods. Poland. From I 976 to 1978 the annual numbers of cases of viral hepatitis among health service workers were 877, 965 and 1113, respect- ively; the respective numbers for the whole population were 929, 1022 and 1165 (Szymborski , personal communication, 1979). Romania. In laboratory workers handling possibly infected blood, serological evidence of infection was recently found in 3.8% of 639 per- sons; 2% were HBsAg carriers and 1.8% were anti-HBs carriers (/84). These rates are close to those of the general population . Another sur- vey (/85) yielded frequent serological evidence of HBV among 544 hospi- tal staff members. The laboratory staff and other employees having direct contact with the patients exhibited a 16.2% rate ofanti-HBs, as compared with other groups; administrative staff 4.4%; healthy persons 4.6%; and blood donors 7.9%. The laboratory staff handling human serum and plasma specimens had an anti-HBs rate of 25%. Union of Soviet Socialist Republics. Birulja et al. (186) reported that from 1960 to 1967 the incidence of viral hepatitis was 1.5-2 times that of the adult general population. Those most often affected were nursing staff and, amongst doctors, specialists in internal medicine, surgery, cancer- ology and stomatology. United Kingdom. In Britain health and safety statistics have included viral hepatitis as an occupational disease since 2 February 1976. In 1976 t~e statistics included 13 cases (187) . A postal survey (/88, 189) of about 250 British laboratories between 1970 and 1974 elicited 73 cases of clinical hepatitis, the overall incidence 47 being 111-143 per 100 000 persons per year, with higher rates for biochem- ist~ and medical haematologists. The annual incidence throughout the years was 5% of 244 in 1970, 7% of 215 in 1971 and 2% of 337 in 1972. A retrospective postal survey of 21 000 medical laboratory workers in England and Wales in 1971 and 3000 in Scotland in 1973 revealed 38 cases of hepatitis (190). A prospective study of hepatitis in 33 of the 48 dialysis units has continued since 1968 (164). In the late 1960s there was an extensive out- break among laboratory workers, but after the introduction of a control and preventive programme in 1970 there was a sustained decline in the incidence of HBV to the low level of0.3% among patients and 0.1 % among staff in 1973 - a greater than 10-fold decrease in 4 years . Among the staff the incidence rate was l.3per 100 persons in 1970,0.8 in 1971,0.4in 1972 and 0. 1 ( one HBsAg carrier doctor) in 1973. Prophylactic immunoglobulin has not been used but there has been scrupulous attention to hygiene , testing of all patients for HBsAg before admission, and dialysis of HPsAg- positive patients in isolation. High-titre hepatitis B immunoglobulin has been held available by the Public Health Laboratory Service as a pre- cautionary measure in case an antigtnaemic patient is detected in a unit or in case of accidental needle prick inoculation in a staff member. Further- more , HBsAg carrier staff members were excluded from work in the unit, though there is no cogent evidence that a hepatitis outbreak has ever originated from a health y carrier among the staff in a dialysis unit in the United Kingdom . In addition the survey raised the question of whether non-B viral hepatitis is becoming a problem in the units. United States. Physicia ns in 1975 and 1976 had an 18.5% rate of prior hepatitis B virus infection (positive anti-HBs) (191) . The infection rate was higher among those practising in urban communities and it increased with yea rs in practice . Amor.g specialists, it was highest in patholo- gists (27%) and surgeons (28% ). In the acquisition of anti-HBs in medical personnel there is an upward trend in older medical students with a considerable increase of the anti-H Bs incidence between 3rd and 4th year students, and house stafi. and faculty. Also the rates are higher among foreign-born house officers (192). In Minnesota 33% of HBsAg-positive patients with known occu- pations, not including hcusewives and students, worked in medically- related vocations (193) . No recent parenteral exposure to hepatitis B could be identified for half of these HBsAg-positive persons. Other serological surveys in hospitals have shown prevalences of HBV seropositivity as follows: 2% in radiologists (194) ; 9-14% in ward person- nel (194,195); 16% in pathologists (195); 12-18% in laboratory workers, in particular chemical technicians (195) ; 25% in black female laboratory 48 housekeepers (194-196); and 36% in non-laboratory housekeepers ( 195). Seropositivity is not correlated with current residence census tract socio- economic indicators for black or white females ( 196). Most, if not all, of the seropositive persons have been asymptomatic and only a few have had a transfusion ( 196) but most of them had worked routinely with blood. Also blood spilt occasionally on computer cards has been associated with an outbreak of 5 cases of hepatitis (197). Moreover, another out- break of 12 HBV cases among the staff of a children's hospital indicated that HBV can be transmitted via a nonparenteral route and illustrated the occupational hazard to medical personnel involved in seemingly innocu- ous and routine multiple transfusions ( 198). The incidence of hepatitis (icteric and anicteric) among Hepatitis Scientific Memoranda laboratory workers in 1973 was 7.4% in the United States and 5.2% for all countries outside the United States (194). The survey included 51 American and 38 foreign laboratories. The number of pers ::mnel studied was 731. Three quarters of the laboratories included in this survey were working with hepatitis-infected materials without inacti- vation before handling and nearly half of the laboratories indicated no form of decontamination after handling. Yugoslavia. The Institute of Occupational and Radiological Health, Belgrade, recorded 57 cases of clinical hepatitis in 1976 and 54 cases in 1977, in particular among nurses and doctors. National statistics on health personnel are not available (Graovac-Leposavic, personal communica- tion, 1979). HBV in dental practice As an occupational group, dentists are at excessive risk of both contract- ing an attack of acute hepatitis 8 and of asymptomatic carriage of HBsAg (199,200). Approximately 5% of post-hepatitis patients continue as asymptomatic carriers of HBsAg, a matter of concern to practising dentists . Although hepatit;s traffic in most dental surgeries is probably an infrequent event, the risk ;s there because dental treatment entails the use of sharp instruments and dental staff come in close contact with blood and saliva, both of which may contain HBsAg. This may constitute a particular hazard for dental and oral surgeons, particularly as the majority of dentists do not use gloves during work and they may frequently be exposed to "net;dle prick" inoculations and, in addition, they often have small cuts and abrasions on their hands. The relative importance of blood and saliva as sources of infection is unknown . Furthermore, the use of ultrasonic rotatory instruments and air and water sprays creates a potentially infectious at:rosol. Glasses and masks of dental surgeons become easily contaminated 49 with aerosol deposits; HBsAg has an unusual stability on various surfaces. In addition, dental personnel offer several potential modes of parenteral and oral-intestinal transmission of hepatitis 8. Positive histories of overt hepatitis among practising dentists have been received from between approximately 5(Jj and 17% of the respond- ents (199) . A high positive correlation exists between the incidence of hepatitis and the number of years in active practice. A German postal survey (201) of 858 dentists indicated that 13.5% had had hepatitis during their professional careers. Five per cent of the younger dentists who had been practising for 1-14 years had been infected. The frequency of hepati- tis infections increased continually to 33% after 35-39 years of profes- sional activity. Subsequently, blood samples were collected from 773 dent- ists and 3.5% were antigen-positive. Compared to the general population the Bavarian dentists involved had a 6- to 30-fold rate of infection. In contrast, Danish dentists cannot be regarded as a hepatitis 8 high- risk group. Aldershvile et al. (202) carried out a study among 1338 dentists (89% of the dentists at the annual meeting of the Danish Dental Associ- ation and 29% of all Danish dentists). None were HBsAg-positive but 8% had anti-HBs. Practising dentists in Canada, the United Kingdom and the United States have shown 4.5-17% incidence rates of hepatitis, 0.6-3% have been asymptomatic HBsAg carriers, 12. 7-57% have been antibody-positive and 13.6-21 % have had an attack, i.e. they have been either HBsAg- or anti-HS-positive (203-206) . American dentists appear to run a risk of hepatitis B virus infection about 2-3 times that of the general population. A recent study in New York (207) revealed a 21 % exposure rate, i.e. I out of every 5 dentists tested showed serological evidence of hepatitis 8 infec- tion . Frequencies do not vary with geographical region in the United States, nor with the size of the community. Dentists in Auckland, New Zealand, have a higher hepatitis 8 infection rate ( 18.6%) than similar groups in America (208). Moreover, the inci- dence of viral hepatitis among Auckland dentists appears to be rising. The fact that, in some countries, dentists are at excessive risk and approximately I% are asymptomatic transient carriers of HBsAg has led to contentious debate about the personal health of dental staff as well as about the risk of dental workers transmitting viral hepatitis 8 to their patients (200,209,210) . Also questions have arisen as to whether the sera of all practitioners should be screened for the presence of hepatitis 8 and whether the carriage of HBsAg should imply any consequent risk in continuing practice. On the basis of the current data it seems important to detect antigen- positive patients by taking a good medical history, emphasizing hepatitis, blood transfusion and drug abuse. Suspect patients should be referred for blood testing. Appropriate precautions when treating HBsAg-positive 50 patients include the use of masks and gloves . They should also be worn by all dental personnel recognized as HBsAg carriers. If an infection is suspected, for instance after an accidental skin puncture, an injection of high-titre hepatitis B immunoglobulin is considered to give adequate pro- tection (205). Hospital dental surgeons may !,e particularly vulnerable because of possible liver disease among patients referred for dental treat- ment. On the other hand hospital dentists can take appropriate pre- cautions whenever the HBsAg status of their patients is known. The chance of acquiring HBsAg from antigen-positive patients seems to be higher when they have underlying chronic liver disease than when they are "only" true carriers of the antigen. All HBsAg-positive dental workers ought to be investigated to determine whether they are healthy carriers or whether they have an underlying liver disease that may be treated . Pro- vided that they take appropriate precautions, current evidence does not warrant any restriction of their working. From a patient's viewpoint there is, on the one hand, a risk of a cross-infection from one patient to another by infected dental instruments and, on the other, a potential hazard of transmission of HBsAg from an antigen-positive dentist to his or her patient. With regard to the first, the risk can be reduced by treating antigen-positive patients at the end of the session. The risk of transmission of virus B hepatitis from an asympto- matic carrier dentist to his patient is less easily defined. Williams et al. followed 237 patients at risk but found neither overt hepatitis nor HBsAg (211). In another study Alter et al. (212) followed for 6- 9 months 228 contacts of HBsAg-positive health care workers but none of the contacts developed HBsAg-positive hepatitis. Both , however , must be considered inconclusive studies. Preventive measures Risk patients are those having acute hepatitis, the mentally retarded and drug abusers. Health personnel run the highest risk of infection when exposed to blood, saliva and other excreta. Good hygiene, including employment of disposable gloves, syringes and needles , etc., education of personnel, screening of patients and per- sonnel for hepatitis, as well as obligatory notification, are considered the most effective preventive measures. Regular monitoring for HBsAg and transamine has been recom- mended by some, while others have questioned the necessity of this since neither a moderately elevated transaminase, nor a positive HBsAg test in an otherwise healthy person would justify restric~ion of professional ac- tivity and ordering bedrest (154,180). The prevention of occupational hepatitis B in medical staff by means of immunoglobulin (HBlg) has been discussed recently (180,213-218) . 51 The comparable transient effect of prompt HBig injection against needle prick exposure was cogently demonstrated by Grady & Lee (213). In order to ensure continuous prevention , repeated injections would be required if there was a likelihood of further exposure. However, long-term hazards of such an approach are known; there is a risk of eventual sensitization. Nevertheless, for protection against si ngle accidental exposure, HBig must be the current treatment of choice although, in order to prevent potentially hazardous reactions, time must be allowed for demonstrating that the intended recipient of anti-HBs is not already carrying HBsAg. After less flagrant exposures conventional immune serum may be used . OTHER MORBIDITY AND MORTALITY STUDIES Retrospective studies of doctors and laboratory personnel have suggested an increased rate of mental and psychiatric illness (219), Hodgkin's dis- ease (220), suicide (221) and congenital malformations in their in- fants (222). Allergic contact dermatitis occupies the most important role among occupational dermatitis, but also toxic dermatitis occurs in health personnel ( 1-3). An incidence of idiopathic venous ~hromboembolism has occasionally been reported in nurses (223). In the past, the medical profession has been associated with high risk of premature death, especially from cardiovascular disease , pulmonary tuberculosis, accidents, violence, alcoholism, drug taking and suicide (224). As reviewed by Asp et al. (225) , however, many mortality studies pub- li shed during the last 30 years indicate that this assumption is not necess- arily true . On the contrary, physicians as a group usually have a lower figure of overall mortality , despite the apparent differences between vari- ous specialist groups and types of work . The latest Finnish mortality figures on all causes, all diseases and accidents, poisonings and violence show that medical and nursing work belong to those professions with the lowest rates (226). CONCLUSIONS The need for health professionals to be aware of the health and safety implications of the energies and materials with which they work is a matter of general consensus. This report does not attempt to be an exhaustive 52 review of the subject but rather affords an informational foundation which will go some way towards answering the need. All information relating to health and safety amounts to a voluminous subject and there are naturally differences of opinion about many specific matters concerning this problematic area. It is noted that while health professions, in general, belong to low-risk vocations, it is considered that certain areas of the subject involve specific recognized health hazards. These include in particular the risk of hepatitis B virus infection and exposure to ionizing radiation and waste anaesthetic gases; ergonomic problems, too, abound, for example in nursing and dentistry. It is also noticed that national statistics in many countries of the European Region fail to provide current data on the incidence of occupational diseases among health professions. It is stressed that WHO has a vital role to play in this area and that it is essential that within the European Region a survey should be undertaken to clarify the present situation and to follow future trends. In this context it is noted that WHO has a long-standing interest in hepatitis and a WHO scientific group is persistently working on the topic. 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Ramsay, L. & Macleod, M.A. Incidence of idiopathic thrombo- embolism in nurses. British medical journal, 4: 446-448 ( 1973). 224. Wright-St Clair, R.E. Causes of death in colonial doctors. New England journal of medicine, 88: 49-51 ( 1978). 225 . Asp, S. et al. Mortality among Finnish doctors, 1953-1972. Scandin- avian journal of social medicine. 7(2): 55-62 ( 1979). 226 . Sault, H. The socio-economic aspect of occupational mortality in Finland. Nordisk foretagshiilsovard. 3: 72-85 ( 1979). 66 Annex 2 LIST OF PARTICIPANTS Temporary advisers Dr C. Courtoux, Medical Inspectorate, Ministry of Labour, Paris, France Dr J.H. Driessen, General Hospital, Dordrecht, Netherlands Dr J. Ferreres, Clinical Hospital, Madrid, Spain Ms G. Hammond, Occupational Health Department, Central Middle- sex Hospital, London, United Kingdom Professor J.M. Harrington, Institute of Occupational Health, Univer- sity of Birmingham, United Kingdom (Rapporteur) Professor J. Indulski, Institute of Occupational Health, Lodz, Poland Dr E. Janssen, IPH Foundation, Homburg (Saar), Federal Republic of Germany Dr B. Kemter, District Hospital. Rostock , German Democratic Republic Dr V. Kodat, Hygiene and Epidemiology Department, Ministry of Health of the Czech Socialist Republic, Prague, Czechoslovakia Dr J. van der Kolk, Ministry of Health and Environmental Protection , Leidschendam, Netherlands ( Chairman) Dr N. Tsaneva, Institute of Hygiene a nd Occupational Health, Sofia, Bulgaria ( Vice-Chairman) Dr H . Vainio , Institute of Occupational Health , Helsinki, Finland Professor C. Vetere, Ministry of Health, Rome. Italy 67 Representatives of other organizations International Council of Nurses Ms G.C. den Hollander, Dordrecht, Netherlands Public Services International Mr S.C. O'Kane, Feltham, United Kingdom Trade Unions International of Public and Allied Employees Mr P. Ducroq, Berlin, German Democratic Republic WHO Regional Office for Europe Dr M.I. Mikheev, Regional Officer for Workers' Health (Secretary) I llllll lllll lllll lllll lllll llll 111 11 1111 11111 .. 0 0 0 0 0 5 8 l "