TL: Current Politics of Radiation Protection in Canada SO: Greenpeace Canada (GP) DT: September 1989 Keywords: greenpeace reports gp nuclear power safety canada workers risks radiation cancer workplace reactors standards / Canadian Labour Congress TASK FORCE ON NUCLEAR ENERGY 1. SUMMARY AND RECOMMENDATIONS Doses of ionizing radiation to workers in the nuclear field are of particular concern at this time for two reasons: 1) both the uranium and nuclear power sectors are in periods of expansion, leading to a larger exposed population of workers; and, 2) there is a great deal of recent evidence in the international sphere which indicates large increases in risk estimates for cancer resulting from exposure to radiation. While evidence for immediately lowering the 'allowable' radiation dose for workers in the Canadian nuclear industry is overwhelming in Greenpeace's view, the Canadian radiation authorities are presently motivated by political and economic considerations to the detriment of working men and women and also the environment upon which we depend. This submission to the Canadian Labour Congress TASKFORCE ON NUCLEAR ENERGY summarizes the history of dose limitations in Canada, reviews the international evidence indicating higher risk coefficients for cancer induction, and points to the current barriers to change operating in the regulatory process. It is suggested that the drive to open new uranium mines in western Canada, coupled with the desire to shield the existing Ontario uranium operations from current market conditions, has motivated Canadian authorities to resist the world-wide movement to lower dose limits, and thus to sacrifice workers' health and well-being to the industry's balance sheet. Despite the wealth of credible evidence supporting the union movement's demands for lower radiation dose limits, the Canadian uranium industry will continue to resist reform due to low uranium prices for the foreseeable future. This has substantial implications for workers in other fields -- health care, reactor operations, radiography - in so far as they are forced to accept an archaic health and safety regime for the sake of one small portion of the radiation-related sector. Notably, this small sector - uranium production - is heavily dominated by the Federal and Saskatchewan governments. Greenpeace submits the following recommendations to the C L C TASKFORCE ON NUCLEAR ENERGY: A. That the Canadian Labour Congress commit substantial financial, research, and political resources to achieving an immediate reduction in the occupational radiation dose limit from 50 mSv per year to 10 mSv per year, in a dose limit reduction programme which will ultimately bring the occupational limit to 5 mSv per year. B. That the CLC similarly commit resources to achieving an immediate reduction in the public dose limit from 5 mSv per year to 0.5 mSv per year. C. That the Canadian Labour Congress call publicly for an immediate halt to new development of uranium deposits until a Federal inquiry with full public hearings has examined all recent evidence in the fields of health physics, dosimetry, radiological health and safety, and radioecology. 2. RADIATION STANDARDS Introduction Greenpeace Canada (founded 1971) is the largest environment organization in Canada with over 150,000 supporting members. Greenpeace International was formed in 1979 as a world-wide federation and now has 22 national offices, including the Soviet Union, and 3.5 million supporting members. Greenpeace International has head offices in Amsterdam. Greenpeace Canada very much welcomes this opportunity to submit evidence to the CLC Taskforce on Nuclear Energy. Although the term "environment" is usually taken to mean the natural biosphere and biota, Greenpeace's concerns have always extended to the human and social sphere, and indeed, Greenpeace has sought to foster good relations with unions and to work closely wherever possible with trade unions on matters of common concern. Recently, Greenpeace Canada has worked closely with an affiliated union, the United Steelworkers of America, in identifying risks to uranium miners and pressing for improvements in safety and emission limits. Internationally, Greenpeace has worked closely with unions abroad for a number of years. Scope of Submission This submission to the CLC Task Force is concerned with the issues of radiation exposure limits and risk estimates in Canada. Risk estimates for the induction of cancer following exposure to ionizing radiation and the limits derived from them are of great interest to unions and employers in the nuclear field, especially given the current plans to expand uranium mining and nuclear power in Canada. The recent major developments in the international sphere, which have resulted in large increases in the risk estimates for radiation-induced cancer, make this a critical moment in the field. This Greenpeace submission describes these developments which point to the need for major reductions in the current radiation standards for Canadian workers and the public. At the outset, Greenpeace Canada reiterates its full support for the CLC's call for an immediate 5-fold reduction in the present limits. In addition, as shown below, there is mounting evidence for even larger reductions to be implemented within the next few years. While exposure of any workers to radiation is a main occupational problem area for the CLC, it is the high level of exposures of uranium mine and mill workers in particular which has become the flashpoint in the recent debate on radiation protection in Canada. This is because of all 'Atomic Radiation Workers' (ARWS) in Canada, uranium miners average the highest exposures. Moreover, according to the latest available data, the average exposures to radon daughters of uranium mine and min workers increased by over 20% from 0.65 Working Level Months (WLMS) in 1985 to 0.79 WLM in 1986. (Ref. 1) This average is higher than the 'action level' set for radon in the home in the United States (0.75 WLM). Present Limits In brief, radiation limits are set after estimates have been made of the risks of ionizing radiation. In recent years, these estimates have risen alarmingly to between 3 and 10 times the risk levels used in 1977 when the present international standards were set. (A detailed note on these rising risk estimates is set out in Annex 1.) As a result, considerable pressure has built up for a major reduction in dose limits in a number of developed countries, and it is expected that the international Commission on Radiological Protection (ICRP) itself may recommend lower limits in 1990. The current radiation limits in Canada are 50 mSv (millisieverts) per year for workers and 5 mSv per year for the public. These limits were first recommended by the ICRP in 1956. Although the ICRP has been criticized on many occasions in the past for its slowness in introducing adequate safeguards and because of its unrepresentative structure, it is still considered by national governments to be a lead agency in the setting of radiation standards. In the case of uranium miners, a separate additional limit of 4 WLMS, approximately equal to 40 mSv, exists for alpha radiation from radon progeny. At present, proposed amendments to the Atomic Energy Control Regulations are before Parliament which, if implemented, would subsume this limit within a cumulative 50 mSv limit for all sources. The Public Limit In 1985, the ICRP stated that exposures to the public should be reduced from 5 mSv to an average of 1 mSv per year, but in Canada the limit remains at 5 msv. The UK's radiation protection body, the National Radiological Protection Board (NRPB), reduced the public level further to 0.5 mSv in 1987, and its Director has publicly stated that there are arguments for reducing it even further to 0.2 mSv.(Ref. 2). Furthermore, the public action level for radon daughters in the home in Canada is equivalent to 40 mSv per year, which is much higher than the UK limit of 20 mSv and the US EPA limit of 7.5 mSv. In order to understand the inadequacy of the present radiation standards, some background history is necessary. History of the Present Limits The basic occupational 50 mSv level was recommended by the ICRP in 1956, following the controversy aroused by the high levels of fallout from the A-bomb and H-bomb tests. In 1977, following increased risk estimates, the ICRP recognized that this limit was too high for its own recommended risk maximum of 1 death per 2,000 workers per year. However, under pressure from the nuclear industry, the ICRP refrained from setting a new lower limit and instead introduced a new concept - ALARA (As Low As Reasonably Achievable, economic and social factors being taken into account). This meant that annual occupational exposures still had to be below 50 mSv, but in addition employers were to try to keep exposures to a minimum, given the realities of the marketplace and corporate citizenship. (A separate note on the inadequacies of the ALARA concept is set out in Annex 2.) Since 1977 many scientists have expressed concern about the high limits, and in 1985, the former Scientific Secretary of the ICRP, Dr D. Sowby, stated that the "acceptable limit was a tenth" of the 50 mSv limit. (Ref. 3). In September 1987, over 800 scientists from throughout the world petitioned the ICRP to reduce the recommended limits by ten times. The ICRP refused to move, although it stated that radiation risk estimates had at least doubled since 1977. Other international scientists have put the increase in risk at 5 - 10 times. In November 1987, a member of the ICRP, speaking on behalf of the Commission stated that the limits "now represent the lower bound of a region of totally unacceptable practice." (Ref. 4). Because of the ICRP's delay, some countries have, for the first time, broken ranks and issued their own lower limits. The UK National Radiological Protection Board estimated that the risks had increased by 3 times, and effectively reduced its limit from 50 to an average of 15 mSv in November of 1987. In 1990 Sweden will be doing the same. The ICRP has stated that it will be issuing new recommendations in mid 1990, and from what the present scientific Secretary has said in February 1989, it appears that some reduction in the limits may occur. (Ref. 5) It is Greenpeace's view that by the time the proposed amendments are scheduled to be in force in Canada, new lower world limits will have been recommended by the ICRP. The Canadian limits, if the amendments pass unchallenged, will entrench the 50 mSv level while the ICRP and other nations bring their limits to as low as 15 mSv. Limits for uranium mine and mill workers In 1982, the ICRP recommended that, for uranium miners, the sum of internal and external occupational exposures should be under 50 mSv per year. In other words, rather than having separate annual limits for external dose (50 mSv) and internal dose (4 WLMs = 40 mSv), as is the case for Canadian uranium workers, there should be only one integrated limit. In 1983, the Atomic Energy Control Board (AECB), Canada's regulatory body for radiation, proposed amendments to the AEC Regulations to bring the ICRP's recommendations into effect, but these were not implemented because of industry opposition. In 1986, the AECB proposed new amendments (C-83) to the Regulations with the same effect, but it has taken 3 years for the union movement to overcome the objections of the industry on this amendment. The essential resistance has come from the industry representatives of the Elliot Lake uranium operations, who assert that "there would be a major impact on their commercial viability" in trying to bring all workers under the revised 50 mSv limit. (Ref. 6) The AECB finally announced in July 1989 that the new "additive dose limit" will apply after April 1991, almost a decade since it was recommended by the ICRP. For uranium miners, this could represent an improvement on their present position in that the maximum level for alpha radiation from radon progeny could decrease in practice in many mines. This will depend on the ore concentrations in each mine. However, for most radiation workers the proposed amendments would entrench limits which are already highly questionable, and which likely will be out of step with the rest of the developed world's limits by the time they are implemented. The impact of new uranium developments As mentioned above, the economic position of the Elliot Lake uranium operations has had a substantial negative impact on radiological health and safety in the last 3 years. The looming obstacle for the Canadian union movement and environmentalists is development of the new, high-grade ore deposits in Saskatchewan. With average grades of up to 12% uranium (400 times higher than Elliot Lake), radiological protection at Cigar Lake will be extremely difficult. A French team studying the problem of radiation in high-grade underground uranium mines found that only 3 hours of unprotected exposure at Cigar Lake levels would give a dose equivalent of 20 years' at the allowable annual dose limit of 50 mSv specified in the new AEC Regulations. This figure accounts for alpha radiation from radon daughters; gamma radiation is not calculated. (Ref. 7) Cigar Lake will be an underground mine, so it is possible to deduce some of the problems inherent in developing the deposit. The Elliot Lake underground operations, according to management, cannot afford to bring all workers under even the 50 mSv limit, let alone a lower one. At the Roxby Downs underground mine in South Australia, cutting the dose limit to 25 mSv per year (i.e. in half) would shut down the operation, according to a member of the S.A. Radiation Protection Committee. (Ref. 8) The ore grade at Roxby Downs is a fraction of that which will be encountered at Cigar Lake. Opposition to lower dose limits, despite overwhelming international evidence to the contrary, can be expected to grow in Canada. The new high-grade mines in Saskatchewan, and particularly Cigar Lake, will hold back the cause of increased radiological protection for a decade or more unless action is taken now. Notably, the Federal and Saskatchewan governments are heavily involved in Cigar Lake, controlling more than 50% of the voting stock. We have seen that economic conditions of uranium production and marketing can have an inordinate influence on questions of health and safety in the industry. This influence is codified in the concept of ALARA. Therefore a discussion of radiological protection can rightfully extend to production costs and market conditions, and in Canada these influences will continue to dominate over strictly health issues. A forthcoming study by Greenpeace International analyzes uranium demand and supply to the end of the century, and relates these to price for the mineral over the same period. The conclusion: uranium prices cannot be expected to rise from their current low level until well into the next century if Cigar Lake, Midwest Lake and Kiggavik come into production. (Ref. 9) Canadians can therefore expect the foot-dragging of the industry over the last 3 years to continue well into the '90's, and probably into the next century. Health protection costs money, and the industry will almost certainly be in a low to nil profit position for the foreseeable future. 3. CONCLUSION In summing up, there are a number of points which should be taken into consideration when examining the question of dose limits. The first is that the history of dose limits has been one of continual reductions. Put simply, since 1934 the more we have found out, the more the limits have had to be reduced. This is true for the limits for radon, for public limits, and at least up to 1956 for worker limits. But the occupational limit has not been reduced since then, and it is now 33 years old. In comparison with the age of other occupational standards, this is very old indeed and this by itself should flag up some concern. Also, as the ICRP public level has been reduced, the normal ICRP ratio of 1 to 10 between the public and worker radiation limits has been breached, which is another cause for concern. However, the most significant point is that since 1977 the risk estimates determined by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) have increased 3 to 10 fold depending on the assumptions used. This by itself should result in the occupational limit being reduced by similar magnitudes. A further point is that when arriving at risk estimates and dose limits, uncertainties and unknowns exist which mean that many assumptions have to be made. Unfortunately, in the past this has resulted in assumptions which have lowered the estimated risks to workers, for example the use of weighting factors, DREFs, arbitrary RBEs; the use of averages instead of estimates for the most affected workers; the use of dose constraints instead of limits since 1977; the use of hypothetically-low population death rates for calculating relative risks; and the ignoring of genetic damage and non-fatal cancers in assessing risks. (For a fuller description of these points, see Annex 1 below.) Given these uncertainties, in Greenpeace's view, risk estimates should always err on the side of caution and be pessimistic rather than optimistic. In particular, where they are expressed in terms of ranges, then the higher estimates should be used rather than the lower ones. Taking all of these factors into account, there remains a very strong body of evidence pointing to the need for major reductions in the dose limits in Canada. ANNEX 1 NOTE ON RISK ESTIMATES Low LET radiation In recent years, there have been major changes in the risk estimates of low LET (linear energy transfer) radiation. One major reason has been the revision, in the early 1980's, of the dosimetry of the largest available data base for risk estimates - the Japanese survivors of the World War II atomic bombs. There has been much discussion in US and UK circles about this revised dosimetry, but the generally agreed upshot has been a 5% to 10% increase in the risks of developing solid tumours, compared with ICRP's 1977 estimates. However, a more important factor has been the adoption of the relative risk model in preference to the additive risk model. The latter presumes that cancers are simply proportional to the dose and numbers exposed. Instead, it is now widely accepted that the rate at which excess cancers develop is a constant fraction of, i.e. is relative to, the naturally-occurring cancer rate in a given population. Because the number of cancers increases markedly with age, the relative risk model results in considerably higher risk estimates than the additive model which has been used hitherto. The end result of these two factors was summed up in the December 1988 report of UNSCEAR, the world body which assesses risks but not limits. This stated that the risks of low LET radiation among the Japanese survivors were now over 11% per Gray, more than 4 times the 2.5% per Gray figure used by UNSCEAR in 1977. More important, they are 8 times higher than 1.25% figure used by the ICRP in 1976 to arrive at the present recommended limits. The new UNSCEAR figures will be used by the ICRP in the near future to arrive at its new recommended dose limits.The current debate now rages over whether and to what extent the following factors should be applied by the ICRP to the UNSCEAR results. A. DREFs (Dose Rate Effectiveness Factors) In recent years, some animal and human studies have suggested that radiation at low dose rates results in fewer cancers than at high dose rates. Consequently, radiation authorities customarily apply a DREF to reduce the risk estimates emanating from the Japanese studies where, of course, the victims received most of their doses instantaneously. For example, UNSCEAR estimates that a DREF of between 2 and 10 should be applied, i.e. that the risk estimates should be divided by this factor. The UK's NRPB estimates that a DREF of 3 is a better figure. However there is still no widespread agreement about the use or the magnitude of DREFS, and some environmental groups have pressed for a lower DREF of 1.5 . B. Cancer incidence and genetic effects At present, the UNSCEAR risk estimates only count cancer deaths; they omit genetic damage after the first two generations and they ignore the pain and suffering of non-fatal cancers. On average, about a third of most cancer sufferers survive. Recently and for the first time, a major regulatory body, the UK's NRPB, stated that these matters should be included in radiation risk estimates. It estimated that a figure of at least 1.1% per Sv should be added to the fatal cancer estimates. If this practice were to be followed by the ICRP in its own risk estimates, this would lead to even lower limits. C. Use of female data for U-miner limits. The use of the relative risk model means that a risk quotient is multiplied by the cancer rate of the population involved, and the average of male and female cancer rates is used. For lung cancer rates, this averaging can lead to anomalies, because lung cancer rates for women in Canada are less than a third of rates for men. On the other hand, there are extremely few women uranium mineworkers in Canada. In other words, only male cancer rates may need to be used in deriving risk estimates for use in limits to be used by uranium mineworkers. High LET radiation In recent years, concern has mounted about the effects of alpha radiation from radon progeny which are present in most homes and in uranium and other mines. This has been due to two main factors. First the latest figures from the Japanese survivors show that the number of lung cancers has increased more than other cancers, which means that radiation may affect the lung greater than previously thought. (Ref. 10). Second, radiation authorities have doubled their estimates of the amount of background radiation received from radon progeny in recent years. (Ref. 11) The risk estimates for alpha radiation are usually derived from the epidemiology of miners exposed to radon progeny, rather than from the Japanese studies, because of the many difficulties in translating external whole-body gamma radiation to internal radiation by alpha particles. These estimates have varied considerably over the past ten years due to the assumptions used in the studies concerned, the choice of cohorts, and the rationales used in treating the raw data. Unfortunately, as a result, most of the studies are not readily comparable. Nevertheless, in order to provide some guidance in this area, the following estimates show the general trend. Table One: Attributable Excess Risk (Deaths Per 106 Person-Year Per WLM) YEAR SOURCE (REF) COHORT RISK ESTIMATES 1980 BEIR III (12) US Uranium Miners 6-9 1983 Muller (13) Ontario Uranium Miners 7.2 1984 Radford (14) Swedish Iron Miners 19 1988 Seve (15) Czech Uranium Miners 20-30 1989 Radford (16) Swedish Iron Miners 29.4 These figures show a broadly rising trend, so that the estimates are now 2 to 3 times higher than earlier estimates at the beginning of the 1980's.These figures tend to reinforce the results being obtained from the Japanese studies discussed earlier. On the other hand, the radon risk studies by the ICRP in 1987 (Ref. 17) and BEIR IV in 1988 (Ref. 18) both give risk estimates for radon progeny to the public which are lower by factors of 3 and 2 respectively than the latest miner epidemiology. Of course, these studies did not use the latest miner results, and in the case of the ICRP study the older miner-derived risk estimates were arbitrarily reduced by one third to account for the differences between miner and public exposures. This assumption together with the assumption of theoretically low base rates for lung cancers in the world resulted in the low risk rates in ICRP 50. It is noteworthy that the US National Academy of Science's BEIR IV report in 1988 did not make the same assumptions in arriving at its risk estimates. ANNEX 2 NOTE ON THE ALARA PRINCIPLE The problem with ALARA is that it gives employers great discretion: in practice, it is up to them whether they reduce exposures or not. On the other hand, specific limits clearly put greater pressure on employers to conform. The nub of the matter is that it is employers alone who decide the "economic and social factors to be taken into account," so that business exigencies and market considerations usually dictate the pace of safety improvements. As a result, in recent years, improvements in reduced exposures have lagged behind perceived risks of radiation. Traditionally, trade unions have much preferred fixed limits to variable constraints and with good reason: they make it much easier for enforcing authorities and the unions themselves to ensure safer workplaces. REFERENCES 1. Dr. J.P. Ashmore, Head, National Dose Registry, Dept. of Health and Welfare, personal communication with Ian Fairlie, Greenpeace Canada, July 1989. 2. Hinkley Point C Inquiry, Transcript of Proceedings, Day 64, Page 56A, February 8, 1989. 3. Canfield, C., Multiple Exposures. p. 183. Secker and Warburg, London, 1989. 4. Berry R.J., "The ICRP - A Historical Perspective", page 122, in Radiation and Health., Jones, R.R. and Southwood, R., editors, John Wiley and Sons Ltd, London, 1987. 5. Smith, H. (Scientific Secretary, ICRP), Report of a Conference on the Effects of Small Doses of Radiation, London, February 1989. 6. AECB Memorandum, Senior Review Group to Board Members, 10 April 1989. 7. Commissariat a I'Energie Atomique (CEA), "Studies of radon hazard reduction in underground mines", Gif-sur-Yvette Cedex, France, 1988. 8 . Denis Matthews, member, South Australia Radiation Protection Committee, personal communication with John Willis, Greenpeace International, July 17, 1989. 9. O'Faircheallaigh, C., "Uranium Demand, Supply and Prices, 1991-2000", Greenpeace International, Amsterdam, forthcoming. 10. Stather, J.W, et. al., Health Effect Models Developed from the 1988 UNSCEAR Report, NRPB-R226, London, 1988. 11. Clarke, R.H, and Southwood T.R.E., "Risks From lonising Radiation", Nature, Vol. 338, March 16, 1989. 12. Committee on the Biological Effects of Ionizing Radiation, The Report of the Committee on Biological Effects of Ionizing Radiation, (BEIR 111), National Academy Press, Washington, D.C., 1980. 13. Muller, J., et. al., Study of Mortality of Ontario Miners 1955-77, Part 1, Ontario Ministry of Labour, Toronto, May 1983. 14. Radford, E.P.,and Renard, S.G.S., "Lung Cancers in Swedish Iron Miners Exposed to Low Doses of Radon Daughters", New England Journal of Medicine, June 7, 1984. 15. Sevc, J., et. al., "Cancer in Man After Exposures to Radon Daughters", Health Physics, January 1988. 16. Radford, E.P., orally reported to the International Conference on lonising Radiation and Cancer Epidemiology, University of Birmingham, UK, July 12-13, 1989. 17. ICRP Task Group, Lung Cancer Risk from Indoor Exposures to Radon Daughters, ICRP Publication 50, Pergamon Press, Oxford UK, 1987. 18. The Committee on the Biological Effects of Ionizing Radiation, Health Effects of Radon and Other Internally Deposited Alpha-Emitters, (BEIR IV), National Academy Press, Washington D.C., 1988. September 1989.