WORLD HEALTH ORGANIZATION
ORGANISATION MONDIALE DE LA SANT~
REGIONAL OFFICE FOR
THE WESTERN PACIFIC
BUREAU R~GIONAL DU PACIFIQUE OCCIDENTAL
REGIONAL CO!lNITI'EE
vTP/RC15/9 16 June 1964 ORIGINAL: ENGLISH
Fifteenth Session Manila 17-22 September 1964 Provisional agenda item 16
PUBLIC HEALTH ASPECTS OF PROl'ECTION AGAINST IONIZING :RADIATION .~
1.
INTRODUCTION
This technical paper is extracted from the report of a "mo Conference on the Public Health Aspects of Protection Against Ionizing Radiation held in DUsseldorf in 1962. It is presented to the Regional Committee for information and d.iscussion on an inij;lortant aspect of health which deserves serious and urgent consideration. 2. SOURCES OF IRRADIATION
2.1 The increasing use of ionizing radiation and the rapid. development of new sources of irradiation are associated with growing health problems and are causing increasing concern. 2.2 The sources of irradiation are: (1)
natural background, sometimes artificially increased by exposure of radioactive strata and d~ing of slag from mining; radioactive substances in construction materials; inhalation and ingestion of radioactive materials; medical and. dental irrad.iation and use of radioactive materials, including release of radioactive patients; fall-out; occupational exposure, both of radiation workers and of other worIters in a nuclear establishment; direct irradiation of the public near or visiting establishments using radiation sources industrially; /(8) sale of
(2) (3)
(4)
page 2
WP/RC1 5/9
(8)
sale of radioactive materials; deliberate irradiation of individ.uals, as in shoefitting machines; transport of radioactive materials; disposal of radioactive wastes; accider.ts.
(9) (10) (11)
(12)
2.3 It is a strildng fact that the biggest contribution at the present time to the irradiation of the population, in addition to natural radiation, is from medical uses of ionizing rad.iations. 2.4 The development of nuclear energy, despite the care which has so far been tal~en in the establishments where it has been employed, constitutes a potential danger because of the enormous quantities of highly radioactive substances involved, the transport of such materials and the accumulation of radioactive wastes for .rhich no method of destruction exists.
,..
3·
RESPONSIBILITIES FOR RADIATION PROTECTION
3.1 Ionizing rad~ation is only one of many hazards to which populations are exposed. in the increasingly complex environment in which we live. 3.2 The irradiation of the population from whatever cause, inclu~ng occupational exposure, is clearly of public health concern because it may provol~, besides the somatic effects, deleterious genetic effects. Thus, public health services have important responsibilities tor radiation protection. The public health services should be entrusted with the protection of the population from the dangers vrhich may result from ionizing radiation.
3.3
4.
FUNCTIONS OF TRE PUBLIC HEALTH SERVICES IN RADIATION PROTECTION
4.1 One of the main functions of the public health services should. be to participate in planning and take part in the action required by the spread of radioactive substances. 4.2 The public health services, in order to discharge their responsibilities, should have functions which include ensuring that there is adequate legislation enabling them to maintain the irradiation of the population at the lowest practical leve~and should have adequate means to implement legislation, covering the following: (1) powers to fix basic standards; / (2) provision .••
page 3
WP/RC15/9
(2)
provision for the public health services to be informed. of all premises where ionizing radiations are used, e.g., through registration or licensing; public health service powers to carry out inspections and require suitable practices and preventive measures to avoid misuses and to ensure that ionizing radiations are used by competent people; po.rers to prohibit unjustifiable uses of ionizing radiations; public health services participation in official decisions as to whether and under ,That conditions major uses, such as atomic energy d.evelopments, are justifiable; responsibility of public health services for periodic estimations of the overall doses received by the population; the functions of public health services should include also the stimulation of scientific research, which is the basis of better understanding of radiation hazards and of improved methods of control; they should play an important role in the education and training of personnel, as .rell as in educating and informing the public concerning the various aspects of the uses and risks of ionizing radiation.
(3)
(4) (5)
(6)
(7)
( 8)
5.
CONTROL OF X-RAY MACHINES
•
5.1 Much can be done to reduce unnecessary irradiation without detriment to the medical benefit of X-ray procedures. The basis of effective control is accurate measurement of dose. 5.2 The dose is determined. by the equipment, installation and accessories, by the techniclues used, and. by the judgment as to 1fhen an X-ray is needed.
5.3 The last is primarily a matter for the medical profe ssion "hich should establish criteria for the guidance of its members. Critical exam; nation of the need for certain X-ray diagnostic procedures has induced greater caution in their use. _ For example, paediatricians are abandoning routine fluoroscopy and pelvimetry is being used less frequently.
5.4 The other t,ro factors which d.etermine the dose are susceptible to e:;..-ternal control. In the United states of America simple procedures for inspection have been d.eveloped which can be carried out by personnel vdth relatively little advanced training. Listed approximately in the order of importance, the follOwing factors can be assessed. by inspectors after modest training: /(1) beam size
~fP/RC15/9 page 4
(1)
beam size; beam alignment; filtration; target-to-skin distance; availability and use of gonadal shields; speed of film; speed of intensifying screens; output of X-ray machines; and tube housing leakage.
(2) (3)
(4) (5) (6)
(7) (8) (9)
5.5 In all but a very few procedures, adequate beam limitation can prevent irradiation of the gonads. Although inspection can checl;: the presence of beam limitation d.evices, it cannot ensure that they are used. A method of survey without on-the-spot inspection has been developed for dental X-ray machines. A film-pack with instructions is sent to a dentist who sends it back for evaluation after per:f'orming the survey. "lith medical X-ray machines the problem is more complex and it seems quite unlilrely.that a substitute for on-the-spot evaluation w.!.ll be developed. A concurrent educational programn:e for physicians, dentists and technicians is therefore necessary. 5. 6 Another need for an education programme is that doctors and dentists in general are not fully avTare of the need to restrict examinations to the minimum necessary for proper treatnent. There should always be a positive need for the examination: it should. not be done as a routine.
6.
CONCLUSION
It should be apparent from the above that the most i~ortant source of artificial irradiation is medical and that with its increasing use for diagnostic and curative purposes, appropriate action has to be talren by the health authorities to ensure the adequate protection of both the population at risk and. the professional worlrers themselves. The fact has been well established in developed countries that more effort and money have been expended on protection against the effects of nuclear energy than against all other industrial hazard.s. The same situation does not, however, exist when it comes to the manufacture of X-ray machines, which are often used daily without sufficient care being talum to ensure that exam; nees and examiners alike are adeCluately protected, nor is enough attention paid in developing countries to the poten.tial.hazards of nuel.ear establishments. / The hazards ...
page 5 The hazard.s are actually, or at least potentially, present in all these situations and it behoves all health authorities to exert their utmost towards their elimination or reduction.
IIP/RC15/9
The Organization ,Till be glad to provide assistance in this ill!Portant field.
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:} .H.O. 15th S.'!;SSIOJ:l OF THE REGIONAL C0l'11HT'rEE F03.l'HE
PACIFIC, NANILA, 17-22 SEPeNBER, 1964 -il:'~STERlT
ITEM NO. 16 Subject: Documents: Comment: DETILOPhEiTT OF R.'c:JIA7ION CO:t<TTROL PROGRiulEES
The Public Health Aspects of Protection Against Ionizing Radiation 1;JP/RC15/9
nr AUSTfiALIA (As at September, 1964)
Introduction Australia is a Federal State and the constitutional responsibility of many aspects of public health rests with the Public Health Authorities of the several States. Thus, at present, the constitutional responsibility for the regulatory control of radiation is th~t of the States. However, in the field of radiological protection, the Com~onwealth Government, mainly through its Department of He~lth, has exercised a res)onsibility of co-ordinating State activities in the field and of providing advisory services and special laboratory facilities. The review of the development and staffing of radiation control programmes which follows is considered under the following headings:1. Federal Aivisory Services 2. Federal Control of the Use of Radio-Isotopes 3. Regulatory Control 4. Laboratory Facilities 5. Special Investigations 6. Education 1. Federal Advisory Services
(a) In 1957, the Commonw'eal th Government established a National Radiation Advisory CommitteG with the responsibility of advising it, directly through the Prime Minister, on any matter concerning the effects of ionizing radiation on the Australian com~unity. The present membership of this Committee includes scientific specialists in the fields of medicine, ?ublic health, genetics, animal health and radiation physics. The National R~diation Advisory Committee has from time to time submitted reports to the Pri~e Minister and in these has reviewed the present state of knowledge of the biological effects of radiation, surveyed present radi~tion levels for the Australian community and made appropriate recommendations. (b) For many years there has existed in Australia a National Be '"-I th tlnd l!~edical Research Council which, among other things, advises the Federal Minister of 5e~lth on public health matters. The members~",i"O of this Council includes the Commonwea.lth Director-General of 3~BI~h and several of his senior medical officers, the Directors-General of Public He~lth of the several States and representatives of the Medical Faculties of the Universities, of the Australian liedical Associatior.., of the Australian Dental Associ~tion s.no. of the Specialist lvledical Colleges.
(Item No.16 contd.) 2
To assist it in its study of public health problems, the Council appoints specialist committees. In the field of radiation control, the National Health and kedical Research Council has ap?ointea the following committees: (a) (b) (c) The Occu~stional Health Committeo, The Radiation Eealth ComDittee, ~he Radio-Isotopes Committee.
At the request of the Council, the Occupational H~alth Committee prepared a Model R~dioactive Substances Act and Regulations. This Model Act and Regulations calls for the licensing of the users of radioactive substances and of irradiating ap-:>aratus in medicine, research and industry and lays down radiological standards and practices, including those for the transport of radioactive substances. The Model Act and Regulations were forwarded to State Governments vith the request that they should implement them on a uniform basis. Action which has been taken is reviewed in a later section. The ~adiation Health Committee wes established by the Council to enquire into and advise the Council on all matters relating to the effects in man of ionizing radiation, from whatever source, and to measures necessary for the prevention of ill health (including genetic or somatic damage) arising from exposure to such radi~tion. This Committee, among other action, has prepared a statement on the "Res~onsibilities of the Medical and Dental Professions in the Use ~f Z-ray ~quipment for Disgnostic Purposes". The statement summarizes the means by ,"'hich radiation exposure to patients may be minimized. It has been circulated by the Council to all members of the medical and dental professions in Australia. ,ifheE artificially-?roduced radio-isotopes first beoame available, the National Yealth and l'iedical Research Council established a Radio-Isotopes Committee and ?laced with it the responsibility of approving all app~ic~tions of radio-isotopes for diagnostic and -';herapeutic purposes on human p~,tients. The procedures adopted are reviewed in more detail in a subsequent section. 2.
Federal Control of the Use of Radio-Isotopes
In 1932, the entry of radioactive elements into the country was placed under the Customs (Prohibited Imports) Regulations. (This control was intended to protect the community from the ~'se of water and appliances claimed to contain small amounts of radium ~nd intended for medical use.) The expanding use of artificially-produced radio-isotopes from overseas sources resulted, in 1951, in the classification under the same Regulations of all radioactive elements, whether naturally-occurring or artificially '.:Jroduced. l'he entry of each shipment of radioactive material is subject to a clearance issued by the Com'TJoD'-realth Director-General of H3alth. The clearance is issued only after an investigation of the particular application and after it has been sho,"m th;;.t the radioactive material will be used both usefully and safely. These Customs RegUlations have ?rovided an effective control during the absence of other regulatory control. ~P+~~~D' Ap.'+~
As mentioned above the Radio-Isotopes Committee of the pp~ Mp~~nBl RA~aarch Council ~un~OVR~ of all
(Item No.16 contd.) 3
applications for radio-isotopes required for diagnostic and therapeutic use on human patients. The ]Jolicy of this Committee in approving requests is as follows:The use of radio-isotopes in medicine (a)
should be determined by clinical necessity after proper evaluation has been made of all possible methods, inc~uding those not involving the use of radio-isotopes; should be carried out only where proper facili~ies are available for safe handling and administration of the radio-isotopes and for evaluation of clinical and physical results; should ~e carried out only ~~ere clinicians experienced in their use are available.
(b)
(c) 3.
Regulatory Control
All States of the Commonwe~lth have taken action in implementing the Model Radioactive Substances Act and Regulations referred to above. The corresponding St&te Acts and Regulations are administered by the Public Health Authorities in the several States. Under the State Acts, R:::-diologic:ll Advisory Councils are set up to consider ap~lications for licences to use radioactive substances and irradiating ap?aratus. The States have established their own radiolo}ical inspection services to assist in the administr~tion of the Acts. In its report of July, 1959, to the Prime Minister, the National R~diation A0.visory Committee recommended that the Commonwealth Government should take steps to accept full responsibility at the earliest possible date for the legislative control of all uses of ionizing radi3tion throughout Australia. This recommendation was made on the need for uniformity of practice throughout the Commonwealth and on the consideration that the potential public health problems inherent in the extensive use of ionizing radiation and of nuclear energy are not limited by State boundaries. 'l.'he recommendation of the N-stional Radiation Advisory Com":dttee is under consideration but in th", meanwhile, the Commonwe~lth Department of Health has continued to co-operate wi th State Public Health Aut:lori ties with a view to maivtaining ,~ uniformity of action in raiiation control. In addition to legislative control of the transport of radioactive substances under the State Acts, the transport of radioactive substances by Air, Sea and Post come within the regulatory control of the Jepartment of Civil Aviation, Department of Shipping and Transport and the Postmaster-GeneralIs Department respectively. In some States, the Railways Department h~s its own regulations which are in conformity with those of the V'l.r10US Radioactive Substances Acts anQ Regulations. 4.
Laboratory Facilities
In 1929, the Commonwealth ~epartment of Health established its Commonwealth X-ray and Radium Laboratory which includes among its functions an a~visory s~r!i~e on questi~ns of radiological protection and laboratory fac111t1es.and serV1ces in "'J.-~" .p~""" 'CJ.-';" T·"l-,n~",t,n"''' ;s availnh1p t.n fl"""",n l"Hnio'1.t,ion
(Item No.16 contd.) 4
protection facilities, and to make radiation monitoring surveys, on request. For m~ny ye~rs it has ?rovided a film-badge service which is available to all r~diation workers at nominal charge. The work of the Commonwealth X-ray ~nd ~adium Laboratory, which carries out the responsibilities of a ns-tional centre for radiological physics, is complemented by State Services in some Australian States. 5. Special Investig~tions and Services (R~dioactive Substances)
To meet ~he need for a close scrutiny of public health problems th~t may arise from the expanding use of radioactive substances the following special investigations and services are typical of those operating or being developed by various Commonwealth and State instrumentaliiies:(i) (ii) environmental surveys of fall-out levels including extensive sampling of food and biological materials; low-level radiochemical facilities to measure s~mples for radio~ctivity and to set up equipment for use under emergency conditions, e.g. a major release of radioactive material; supervision of the health of persons engaged in the mining of radioactive ores; whole-body monitoring equipment and facilities.
(iii) (iv) 6.
Education
Responsible authorities in Australia have a?preci~ted the need for a programme of education to produce a range of persons competent in the field of radiation control. In addition it is felt that there should be a wider dissemination of basic knowledge among those who may have contact with radiation and radiation sources. The National I-i2alth and Medical Research Council has requested the Deans of ~he Faculties of Medicine and Dentistry in the various Universities to place greater emphasis on possible radiation effects, and on the need for adequ~te radiation protection, in under-graduate teaching. Similarly an approach has been made by the l~ational Health and l~edical Research Council to Medical and Dental Post-Graduate Teaching Organizations to include information in this field in post-graduate lectures and courses. The College of 2adiologists of Australasia has an entrance ezamination for its membership and courses for this post-graduate qualification include lectures on radiation protection, with particular reference to the protection of patients and staff. Qualific8.tion as a radiographer CA.-ray technician) is gained through examination. The courses for the Certificate of the Conjoint Board of the College of Radiologists of Australasia and the Australasian Institute of Radiography include lectures on radiation protection.
=_
w
(Item No. 16 contd.) 5
The College of Nursing, in ~ssociation with such bodies as the Cancer Institute Board (Victoria), conducts courses in radiotherapeutic nursing and again emphasis is placed on radiation protection. The Commonwealth X-ray and R~dium Laboratory from time to time conducts courses on the Principles of Radiological Protection. These courses are intended for medical and scientific officers in industry and research. Short-term post-graduate courses in radio-isotope techniques are !l.vaib,ble in several Uni versi ties and Institutes of Technology. 'rhese courses invariably ir..clude lectures on radiation protection. As yet no formal courses in radiological health physics as such have been arranged fro under-graduate study. As in most other countries, there is a shortage in Australia of experienced radiological health physicists. The gap is being bridged by practical training in established laboratories until the number of science graduates from Universities can satisfy the demand •
.