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Lessons of Chernobyl: A commentary
Environment International, Vol. 14, pp. 201-203, 1988
0160-4120/88 $3.00 + .00 Copyright © 1988 Pergamon Press plc
Printed in the USA. All rights reserved.
LESSONS OF CHERNOBYL: A C O M M E N T A R Y Jorma K. Miettinen University of Helsinki, Helsinki, Finland (Received 14 April 1988; Accepted 24 May 1988) The Chernobyl accident was a major economic loss with a cost of about $12.5 billion U.S. dollars to the government of the Soviet Union. However, in terms of h u m a n loss it was less than a major accident. The economic costs in countries other than the Soviet Union were caused by reasons other than established radiation protection principles. The lack of preparedness of most countires was demonstrated by exaggerated reporting by the news media and by the confused actions of governments.
Two years have passed since the Chernobyl accident, the worst nuclear power disaster so far. Many reports have been published on it and its consequences. This issue contains results of studies on fallout and radiation doses performed in different countries during these past two years. New scientific information on fallout is obtainable from the Chernobyl emissions because of two reasons: the origin, temperature, emission hight, etc. were different than in the nuclear test explosions and the methods and instruments are now much advanced in comparison to those of the 1960s. In addition to scientific information, the Chernobyl accident provided even more important lessons to our society. The accident was unexpected, surprising and dramatic but its impact was further enhanced by the great delay of factual information and by the unpreparedness of our society. The chaos of media information, confusion of authorities, contradictory statements by several experts and hysteria of the public were greater than the realities of the accident warranted. Chernobyl was the first nuclear power plant accident in which human lives were lost: two men died due to mechanical and thermal trauma and 29 due to accute radiation exposure during fighting the graphite fire within the reactor core. Additional individuals, 200, developed accute radiation syndromes of various degrees and were hospitalized. Inhabitants primarily within 30 km zone were evacuated, but they had no radiation symptoms. The economic costs to the Soviet Union was considerable: eight billion rubles, or about 12.5 billion (U.S.) dollars. For human loss it was a medium, for economic loss a major industrial accident. There were economic losses in other countries too,
but in most cases the actions taken were not justified by radiation protective requirements. The authorities and experts were evidently carried away by the general radiation hysteria. In the news media the situation was aggravated by the fact that some western news agencies and even governments continued to disseminate patently wrong information (e.g., "t w o reactors burning, 10,000 killed in Kiev") long after correct information was available. Even though this partly political misinformation was then corrected, radiation fear persisted in the public and grossly distorted perception of the risks of reactor accident and of subsequent fallout. The military beginnings of the Nuclear Age and the longstanding nuclear arms race has helped the opponents of the nuclear power to give the general public a misleading picture that the reactor accidents could become a major threat to the environment. The worst accident with western reactors (which are provided with a containment), that of the Three Mile Island power station in Harrisburg, USA in 1979 emitted negligible amounts of radioactivity with insignificant health hazards. Chernobyl represents the worst conceivable accident in which some 50% of the relatively volatile radionuclides escaped from the core, but the fallout caused no immediate health hazard outside the emergency zone around the reactor. In Finland, where the average dose probably was of the highest order outside the Soviet Union, it was 0.4 mSv/y in the first year, a 10% addition to the normal background dose of approximately 4 mSv/y. The deviation of radiation dose in various parts of Finland exceeds the contribution from Chernobyl. The unpreparedness of Europe to handling radiation 201
202 accidents of that scale became evident in many ways. There were great differences between states and even provinces in the intervention levels, although all were basing their action levels on International Commission on Radiological Protection (ICRP) recommendations. One reason for this was that the radiation safety experts were divided into two groups: pragmatists and idealists. Pragmatists based their judgements o f a need o f intervention on ICRP (1984) which sets action levels for situations resulting from accidental (i.e., short term) releases from uncontrolled sources. In contrast, idealists wanted to use for the Chernobyl e m e r g e n c y the protection measures provisioned for normal operation o f the nuclear installation, which reduce even the minute doses during the life time of the members of the public. F o r the individuals o f a critical group the action levels can be chosen according to ICRP between 5 and 50 mSv/y in the first year. No action is r e c o m m e n d e d if the first year dose will remain below 5 mSv because most interventions have some deleterious effects. Even such seemingly harmless interventions as warnings not to drink clean rainwater or eat nettle or let children play in the sandbox may cause psychological damage to mothers influenced by radiation hysteria. On the other hand, when the upper limit of 50 mSv/y will be exceeded in the first year, it is almost always advisable to start considering countermeasures to limit the radiation dose as much as reasonably feasible. Actually, it is misleading to call these dose levels " l i m i t s " because this implies that exceeding them might be immediately perilous. This is not so. The ICRP also sets dose limits to normal conditions (ICRP, 1977) when the source is controllable. This limit was recently reduced from 5 to 1 mSv/y to the general public, if the exposure is continuous. However, for the first year the 5 - m S v is still valid. In normal conditions the A L A R A (as low as reasonably achievable) principle is valid too. The idealists wanted to apply the A L A R A principle to the food items contaminated with the Chernobyl fallout even though the first year dose was going to be of the order of 0.5 mSv only. T h e y considered the contaminated food as a secondary source which could be " c o n t r o l l e d " by destroying it. This controversy was probably due to the fact that only a small part o f the radiation protection or "health p h y s i c s " professionals have a personal experience of the rather complicated problem of how organ or body doses are derived from radionuclide concentrations in the foods. Only those who have carried out such studies by the whole body counting or radiochemical analysis could tell the relationship right out. Another source of contradiction was the longstanding discrepancy regarding the dose-effect relationship in the low-dose area. Many of the idealists do not seem to recognize that the linearity o f this relation-
J.K. Miettinen ship is only a hypothesis and an administrative decision adopted 30 years ago, because it is prudent and simple. Small radiation doses, of the order of normal background radiation, may be harmful or beneficial to health, we simply do not yet know. The common practice of multiplying 0.5 mSv/y with a large population number and a risk coefficient provides limits and hypothetical risks. The effect may be nonexistant. From these two schools of professionals the administrators and the news media obtained quite contradictory statements regarding the radiation risk and need of protective measures. The confusion was partly due to the fact that scientists do not always understand well news reporting and cannot explain the scientific subject in lay language. The greatest nuclear accident and up to hundredfold m o m e n t a r y increase in environmental radiation level were in too great a contradiction to the experts' statements that there was no major radiation risk to the public. Most journalists are inherently sceptical regarding all " b i g " industry, nuclear included. T h e y would often rather believe opponents rather than the proponents, when both seem to speak with similar scientific authority but give diametrically opposing statements. According to "Society of Nuclear Medicine Newsline" (Ketchum, 1987) "100,000 to 200,000 wanted pregnancies were aborted in Western Europe because physicians mistakenly advised patients that the radiation from Chernobyl posed a significant health risk to unborn children." If this is true, even though the n u m b e r would be smaller, this human tragedy competes with that which took place within the destroyed p o w e r station itself. In some countries stable iodine was administered to children a day or two after the radioiodine containing cloud arrived, in order to reduce further intake from air and from food ingestion, because, with no information on the source, it was not possible to forecast the size and duration of the release. Early notification on the accident would make this measure more effective or not necessary. If stable iodine is administered before or within an hour of the uptake, only 15% of the radioiodine in the blood is taken up by the thyroid, but if the stable iodine is given several hours after a single intake o f radioiodine it has hardly any effect at all. In the case of Chernobyl accident the intake of radioiodine was, however, not a single one, but in some countries continued for several days by inhalation and still longer by ingestion. The early detailed information on the source terms might have enabled to start the stable iodine prophylaxis before arrival of the Cher'nobyl cloud to particular countries or perhaps to reach a decision of not starting it at all. The Chernobyl accident as well as the Goiania radiation accident in Brazil last year showed how unprepared the world still is for the Nuclear Age. On the other hand, in many countries the general public is
Lessons of Chernobyl
mislead to believe .that environmental radioactivity from peaceful nuclear power is the major risk for the society. Lead by the antinuclear movement the public demands zero risk regarding nuclear power and radiation, while accepting many times greater risks from other means of producing energy and more common risks like tobacco, alcohol, dangerous sports, etc. Professionals of radiation sciences have a moral obligation to do their best to correct the distorted public perception regarding radiation risks. They are a complicated matter, yet they are much better known than many other environmental risks (e.g., chemical pollutants). Living is a risky thing. We can never reach absolute security, but with modest knowledge of the relative importance of the greatest risks in our society we can
203
greatly improve the quality of our life and that of our grandchildren. The Chernobyl accident was a bitter lesson in perception of these risks. It demonstrated that in the case of nuclear energy both the public and the professionals have a great amount to learn. References International Commission on Radiological Protection (1984) Protection of the public in the event of radioactive accidents: Principles for planning. JCRP 40, Pergamon Press, Oxford. International Commission on Radiological Protection (1977) Recomendations of the international commission on radiological protection. Report 26, Pergamon Press, Oxford. Ketchum, L. E. (1987) Lessons of Chernobyl: SNM members try to decontaminate world threatened by fallout - - Experts face challenge of educating public about risk and radiation, J. Nuclear Med. 28, 933-942.
0160-4120/88 $3.00 + .00 Copyright © 1988 Pergamon Press plc
Printed in the USA. All rights reserved.
LESSONS OF CHERNOBYL: A C O M M E N T A R Y Jorma K. Miettinen University of Helsinki, Helsinki, Finland (Received 14 April 1988; Accepted 24 May 1988) The Chernobyl accident was a major economic loss with a cost of about $12.5 billion U.S. dollars to the government of the Soviet Union. However, in terms of h u m a n loss it was less than a major accident. The economic costs in countries other than the Soviet Union were caused by reasons other than established radiation protection principles. The lack of preparedness of most countires was demonstrated by exaggerated reporting by the news media and by the confused actions of governments.
Two years have passed since the Chernobyl accident, the worst nuclear power disaster so far. Many reports have been published on it and its consequences. This issue contains results of studies on fallout and radiation doses performed in different countries during these past two years. New scientific information on fallout is obtainable from the Chernobyl emissions because of two reasons: the origin, temperature, emission hight, etc. were different than in the nuclear test explosions and the methods and instruments are now much advanced in comparison to those of the 1960s. In addition to scientific information, the Chernobyl accident provided even more important lessons to our society. The accident was unexpected, surprising and dramatic but its impact was further enhanced by the great delay of factual information and by the unpreparedness of our society. The chaos of media information, confusion of authorities, contradictory statements by several experts and hysteria of the public were greater than the realities of the accident warranted. Chernobyl was the first nuclear power plant accident in which human lives were lost: two men died due to mechanical and thermal trauma and 29 due to accute radiation exposure during fighting the graphite fire within the reactor core. Additional individuals, 200, developed accute radiation syndromes of various degrees and were hospitalized. Inhabitants primarily within 30 km zone were evacuated, but they had no radiation symptoms. The economic costs to the Soviet Union was considerable: eight billion rubles, or about 12.5 billion (U.S.) dollars. For human loss it was a medium, for economic loss a major industrial accident. There were economic losses in other countries too,
but in most cases the actions taken were not justified by radiation protective requirements. The authorities and experts were evidently carried away by the general radiation hysteria. In the news media the situation was aggravated by the fact that some western news agencies and even governments continued to disseminate patently wrong information (e.g., "t w o reactors burning, 10,000 killed in Kiev") long after correct information was available. Even though this partly political misinformation was then corrected, radiation fear persisted in the public and grossly distorted perception of the risks of reactor accident and of subsequent fallout. The military beginnings of the Nuclear Age and the longstanding nuclear arms race has helped the opponents of the nuclear power to give the general public a misleading picture that the reactor accidents could become a major threat to the environment. The worst accident with western reactors (which are provided with a containment), that of the Three Mile Island power station in Harrisburg, USA in 1979 emitted negligible amounts of radioactivity with insignificant health hazards. Chernobyl represents the worst conceivable accident in which some 50% of the relatively volatile radionuclides escaped from the core, but the fallout caused no immediate health hazard outside the emergency zone around the reactor. In Finland, where the average dose probably was of the highest order outside the Soviet Union, it was 0.4 mSv/y in the first year, a 10% addition to the normal background dose of approximately 4 mSv/y. The deviation of radiation dose in various parts of Finland exceeds the contribution from Chernobyl. The unpreparedness of Europe to handling radiation 201
202 accidents of that scale became evident in many ways. There were great differences between states and even provinces in the intervention levels, although all were basing their action levels on International Commission on Radiological Protection (ICRP) recommendations. One reason for this was that the radiation safety experts were divided into two groups: pragmatists and idealists. Pragmatists based their judgements o f a need o f intervention on ICRP (1984) which sets action levels for situations resulting from accidental (i.e., short term) releases from uncontrolled sources. In contrast, idealists wanted to use for the Chernobyl e m e r g e n c y the protection measures provisioned for normal operation o f the nuclear installation, which reduce even the minute doses during the life time of the members of the public. F o r the individuals o f a critical group the action levels can be chosen according to ICRP between 5 and 50 mSv/y in the first year. No action is r e c o m m e n d e d if the first year dose will remain below 5 mSv because most interventions have some deleterious effects. Even such seemingly harmless interventions as warnings not to drink clean rainwater or eat nettle or let children play in the sandbox may cause psychological damage to mothers influenced by radiation hysteria. On the other hand, when the upper limit of 50 mSv/y will be exceeded in the first year, it is almost always advisable to start considering countermeasures to limit the radiation dose as much as reasonably feasible. Actually, it is misleading to call these dose levels " l i m i t s " because this implies that exceeding them might be immediately perilous. This is not so. The ICRP also sets dose limits to normal conditions (ICRP, 1977) when the source is controllable. This limit was recently reduced from 5 to 1 mSv/y to the general public, if the exposure is continuous. However, for the first year the 5 - m S v is still valid. In normal conditions the A L A R A (as low as reasonably achievable) principle is valid too. The idealists wanted to apply the A L A R A principle to the food items contaminated with the Chernobyl fallout even though the first year dose was going to be of the order of 0.5 mSv only. T h e y considered the contaminated food as a secondary source which could be " c o n t r o l l e d " by destroying it. This controversy was probably due to the fact that only a small part o f the radiation protection or "health p h y s i c s " professionals have a personal experience of the rather complicated problem of how organ or body doses are derived from radionuclide concentrations in the foods. Only those who have carried out such studies by the whole body counting or radiochemical analysis could tell the relationship right out. Another source of contradiction was the longstanding discrepancy regarding the dose-effect relationship in the low-dose area. Many of the idealists do not seem to recognize that the linearity o f this relation-
J.K. Miettinen ship is only a hypothesis and an administrative decision adopted 30 years ago, because it is prudent and simple. Small radiation doses, of the order of normal background radiation, may be harmful or beneficial to health, we simply do not yet know. The common practice of multiplying 0.5 mSv/y with a large population number and a risk coefficient provides limits and hypothetical risks. The effect may be nonexistant. From these two schools of professionals the administrators and the news media obtained quite contradictory statements regarding the radiation risk and need of protective measures. The confusion was partly due to the fact that scientists do not always understand well news reporting and cannot explain the scientific subject in lay language. The greatest nuclear accident and up to hundredfold m o m e n t a r y increase in environmental radiation level were in too great a contradiction to the experts' statements that there was no major radiation risk to the public. Most journalists are inherently sceptical regarding all " b i g " industry, nuclear included. T h e y would often rather believe opponents rather than the proponents, when both seem to speak with similar scientific authority but give diametrically opposing statements. According to "Society of Nuclear Medicine Newsline" (Ketchum, 1987) "100,000 to 200,000 wanted pregnancies were aborted in Western Europe because physicians mistakenly advised patients that the radiation from Chernobyl posed a significant health risk to unborn children." If this is true, even though the n u m b e r would be smaller, this human tragedy competes with that which took place within the destroyed p o w e r station itself. In some countries stable iodine was administered to children a day or two after the radioiodine containing cloud arrived, in order to reduce further intake from air and from food ingestion, because, with no information on the source, it was not possible to forecast the size and duration of the release. Early notification on the accident would make this measure more effective or not necessary. If stable iodine is administered before or within an hour of the uptake, only 15% of the radioiodine in the blood is taken up by the thyroid, but if the stable iodine is given several hours after a single intake o f radioiodine it has hardly any effect at all. In the case of Chernobyl accident the intake of radioiodine was, however, not a single one, but in some countries continued for several days by inhalation and still longer by ingestion. The early detailed information on the source terms might have enabled to start the stable iodine prophylaxis before arrival of the Cher'nobyl cloud to particular countries or perhaps to reach a decision of not starting it at all. The Chernobyl accident as well as the Goiania radiation accident in Brazil last year showed how unprepared the world still is for the Nuclear Age. On the other hand, in many countries the general public is
Lessons of Chernobyl
mislead to believe .that environmental radioactivity from peaceful nuclear power is the major risk for the society. Lead by the antinuclear movement the public demands zero risk regarding nuclear power and radiation, while accepting many times greater risks from other means of producing energy and more common risks like tobacco, alcohol, dangerous sports, etc. Professionals of radiation sciences have a moral obligation to do their best to correct the distorted public perception regarding radiation risks. They are a complicated matter, yet they are much better known than many other environmental risks (e.g., chemical pollutants). Living is a risky thing. We can never reach absolute security, but with modest knowledge of the relative importance of the greatest risks in our society we can
203
greatly improve the quality of our life and that of our grandchildren. The Chernobyl accident was a bitter lesson in perception of these risks. It demonstrated that in the case of nuclear energy both the public and the professionals have a great amount to learn. References International Commission on Radiological Protection (1984) Protection of the public in the event of radioactive accidents: Principles for planning. JCRP 40, Pergamon Press, Oxford. International Commission on Radiological Protection (1977) Recomendations of the international commission on radiological protection. Report 26, Pergamon Press, Oxford. Ketchum, L. E. (1987) Lessons of Chernobyl: SNM members try to decontaminate world threatened by fallout - - Experts face challenge of educating public about risk and radiation, J. Nuclear Med. 28, 933-942.