(Une version en français a été publiée dans Radioprotection et Droit nucléaire, [sous la direction de Ivo Rens et Joel Jakubec, Ed.Georg, collection SEBES, 1998) sous le titre "Responsabilités occidentales dans les conséquences sanitaires de la catastrophe de Tchernobyl, en Biélorussie, Ukraine et Russie" pages 247-261.

Introduction

The accident at Chernobyl nuclear plant has to be considered as an unprecedented catastrophe in the industrial world given the scale of radioactive polluted land, the levels of contamination and the huge number of people affected.

Since the beginning of the nuclear crisis after Unit-4 had exploded, Western pressure has been exerted to minimize the health impact evaluation of the accident regarding the long term effects of low levels of radiation (cancer and genetic effects) which will affect the inhabitants of the ex-USSR(1) exposed to radiation. In fact, quite unexpected health problems emerged shortly after the accident giving rise to an obvious increase of morbidity especially amongst children. They pushed into the background the delayed effects of radiation but, like these effects, they have not only been minimized but even denied by the Soviet authorities and by Western experts as well.

To dismiss the field-observations made by local medical doctors it is often said that they did not correspond to the effects observed on A-Bomb Japanese survivors. But the point is that the two situations are not identical at all. In Hiroshima and Nagasaki the exposure to radiation was essentially external and the flash lasted a very short time (the follow-up began only five years after the bombings). After Chernobyl the "emergency phase" lasted a long time (huge amounts of radioactive releases continued all through the month of May) and exposed people to external radiation from the plume and from ground radioactive deposits, but also to internal radiation by inhalation of radioactive air and ingestion of heavily contaminated food. Then followed a phase of chronic exposure, internal exposure essentially through ingestion of food contaminated by a cocktail of radionuclides. No reliable data exist for such a situation : Chernobyl is the first large-scale "experiment" of this kind in the world.

Radiation-controlled zones(2) have been decreed in the Ukraine, Byelorussia and Russia, where caesium-137 ground deposition densities were higher than 5 curies per km² (Cs137>5 Ci/km²) [1]. More than 800 000 inhabitants were living on these areas [2] and more than 7 million on territories with radioactive caesium pollution above 1 Ci/km² (see annex).

As time elapsed, worsening of people's health, especially children's, caused great anxiety and complaint among the population. Later on, street demonstrations took place : people wanted to be evacuated from contaminated areas. The definite position taken in favour of people's demands by eminent members of the Academy of Sciences both in the Ukraine and in Byelorussia, quite a very unusual situation in the USSR (and in other countries), have obliged Republican and Moscow authorities to consider the necessity of new evacuations. In July and October 1989, the Byelorussian authorities released "relocation" plans concerning about 120 000 of the most exposed inhabitants of the so-called zones of strict radiation control (Cs137>15 Ci/km²), with some villages far away from Chernobyl, more than 200 km.

With the help of Western experts, Moscow authorities have been very efficient in opposing the complete realization of these plans and their extension to the whole of the zones under radiation control. Quite obviously the essential concern of these experts was related to the management of a possible nuclear crisis in their own country.

We will chronologically summarize some significant facts from the point of view of post-Chernobyl health problems.

Vienna, 25-29 August 1986. IAEA International Experts' Meeting. First evaluation of the health consequences in the aftermath of Chernobyl

Attended by worldwide experts and organized by the International Atomic Energy Agency (IAEA), this conference aimed to analyse the accident at the Chernobyl nuclear plant and its consequences. The different study groups' sessions took place behind closed doors and information was released to journalists in daily press-conferences (seemingly with no protest against this kind of "information").The Soviet delegation, headed by V. Legasov, presented a voluminous report (370 pages), a general main part and 7 annexes dealing with more specialized questions [3]. Annex 7 was completely devoted to "Medical-Biological problems" and was at the origin of an intense dispute.

Besides detailed data related to acute radiation injuries which have affected the people sent into very "hot" places close to the destroyed reactor and exposed then to very high doses (on-site personnel, firemen who struggled with the burning reactor etc.) and on whom were tried unsuccessful bone marrow transplantation, the report not only made an estimation of the external doses received by the 135 000 evacuees from the 30 km area around the nuclear plant which became the "prohibited zone", but also dealt with the long-term health consequences of the accident for 75 million inhabitants of the European part of the Soviet Union. Their external collective dose was estimated and also their internal collective dose for a period of 70 years due to chronic contamination by radioactive caesium.

With the hypothesis recommended in 1977 by the International Commission on Radiological Protection(3) (ICRP) of a linear relationship between the number of fatal radiation-induced cancers and the exposure dose [without a threshold], it was possible, taking into account the ICRP risk factor of the fatal cancer excess per unit dose of radiation and knowing the collective doses, to calculate roughly the number of long term radiation-induced cancer deaths [4]. Annex 7 gave also the approximate number of thyroid cancer deaths due to radioactive iodine intake. (The Soviet report did not consider strontium-90 but indicated that it might become important afterwards).

There was a general outcry : the estimate of the long-term impact of the Chernobyl catastrophe on cancer mortality was a possible range of 30 000-40 000 extra deaths (more than 80% due to caesium) in 70 years representing up to 0.4% of the normal number of cancer deaths. These numbers were considered too high by Western experts.

At the press conference on August 26th, Dan Beninson, chairman of the study group on the health consequences of Chernobyl said that these Soviet figures were " extremely overestimated ". For Morris Rosen, Director of the Safety Division at the IAEA, the upper limit for the number of deaths was 25 000 and it fell down to 10 000 two days later and Beninson's to 5 100 [5]. At that time Beninson was chairman of the ICRP and people set great value on his opinion (he was also top official of nuclear energy in Argentina). For Beninson and Rosen the Soviet figures were too high because caesium internal contamination had been overestimated. Let us point out that such an affirmation could not have had any scientific basis at that time.

This annex 7, very troublesome for promotors of nuclear energy, has in fact been almost completely censored. Only a few people were made acquainted with its existence. In France, the main report was translated and widely distributed but not the annexes. Afterwards, Soviet and Western experts never referred to this annex 7 as if it had never existed.

Revision of the initial estimation

As early as october 1986 the internal dose was 10 times too high according to some European experts [6]. In January 1987 " After a five days visit in USSR top IAEA officials called the first post-accident assessments of damage health effects "apparently too pessimistic" and should be decreased by a factor five to seven " [7].

To gain credibility the re-assessment had to be worked out by Soviet experts themselves. It was started during the first Vienna IAEA meeting and specified afterwards.

May 1987 : at the WHO conference in Copenhagen [8], resulting from " evidence of a positive trend of the radiation hygiene situation as a result of the implementation of large-scale protective and preventive measures " A. Moiseev reduced the previous external dose estimate by a factor 1.45 and the internal dose by a factor between 7 and 10.5. Nevertheless he admitted that one year after the catastrophe an important proportion of local milk in Byelorussia was still contaminated above the Cs137 permissible levels and " had to be withdrawn from direct consumption and sent for reprocessing " but he did not give any information about this process. One might question if this milk was not sent to remote regions of the USSR (Armenian powdered milk was analysed by CRII-RAD, an independant French association, and high levels of radioactive caesium were found [9]). Let us recall that "democratisation" of radiation doses by increasing the number of exposed people, each person receiving a smaller dose, does not change the final balance : the same collective dose leads to the same number of fatal radiation-induced cancers with the linear relationship (without a threshold) recommended by the ICRP between the number of cancers and the total dose [4]. By adding that the values given in his communication must be " considered as "upper" estimates of the radiological consequences of Chernobyl " Moiseev, in fact, went back to a model with a threshold.

September 1987 : L. A. Ilyin and O. A. Pavlovskij presented a new report on the Radiological consequences of the Chernobyl accident in Vienna at the IAEA's international conference [10]. The subtitle of their report was " Analysis of data confirms the effectiveness of large-scale actions to limit the accident's effects ".

According to the authors, right after the accident the decision was taken to evacuate 115 000 people, including the inhabitants of Pripyat, to prevent them from receiving whole body and thyroid doses up to the emergency dose limits prevailing at that time in the USSR. (The 18 700 inhabitants of Byelorussia evacuated between June and August 1986 are not mentioned). The report indicated that " a total of 5.4 million people including 1.7 million children received iodine prophylactically " [against radioactive iodine]. Introduction of large-scale measures to protect the public, such as standards for foodstuffs, have been efficient especially the interdiction of milk exceeding the permissible iodine-131 level of 3 700 becquerels per liter (3 700 Bq/l). Average infant thyroid doses were given for the northern most contaminated regions of the Ukraine while for Byelorussia the average is reported for all the country(4).

No increase of morbidity was observed in children and no difference between "dirty" (contaminated) and "clean" areas. For the first time radiation phobia syndrome was mentioned.

The estimate of the collective effective dose equivalent p4commitment for the whole Soviet population (278 million inhabitants) through ingestion of radioactive caesium was 18 times lower than the first 1986 estimate for only 75 million inhabitants. In April 1988 L. A. Ilyin re-increased this dose [11] and finally the United Nations Scientific Committe on the Effects of Atomic Radiation in its UNSCEAR 1988 Report averaged Ilyin's two estimates and therefore reduced the 1986 estimate of annex 7 by 9 [12]. M. Beninson should have been pleased with this new value.

Both Ilyin and Pavlovskij were in the list of authors of the 1986 Soviet report. Therefore their 1987 and 1988 articles quoted above should be considered as a true self-criticism.

The collective dose reduction was supposed to be the result of countermeasures efficiency. This official optimism was in complete disagreement with V. Legasov's testament published in Pravda (May 20th, 1988) in which he gave evidence of the incredible lack of care which followed the Chernobyl catastrophe [V. Legasov killed himself on the second anniversary of Chernobyl][13]. The supposed effectiveness of countermeasures is rather doubtful, given the well known ineffectiveness of Soviet bureaucracy and the shortage of "clean" food which should have been imported into zones of strict control, given also the number of the rural population accounting for almost half of the 75 million people of annex 7, with a self-sufficient way of life, consuming local "dirty" foodstuff (just after the accident iodine-131 levels in cow's milk reached 1 million Bq/l in some districts of Byelorussia [3]). Heavily contaminated meat was partly destroyed in Byelorussia but was also exported to be mixed up with "clean" meat [14]. Meat above permissible levels of Cs137 was sold even in Moscow [15]. Standards for tea were introduced in quite a "democratic" way, depending on the regions and the kind of consumers. For example cleaner tea was sold in Moscow and heavily contaminated regions than in factory cafeterias and in less contaminated areas [1]. In the Ukraine people were advised only in July 1989 of restrictions against the picking of mushrooms, wild berries and medicinal plants [16].

Private information began to arrive in France : in contaminated regions of the Ukraine and Byelorussia the health of inhabitants was worsening, complaints against the authorities were growing (as shown in Microphone, a film by G. Shkliarevski and V. Kolinko). Detailed maps of radiation-controlled zones with Cs137 levels above 5 Ci/km², were published in Sovetskaya Byelorussia (February 9th, 1989) showing their extent. From the article one could get an idea of the large number of people affected in their daily life : food monitoring, supply of "clean" food if local food was too "dirty", medical care, advice to use special tractors with airtight cabs, small bonus of monthly "danger money" etc. [1]. The chairman of the Byelorussian Council of Ministers has summarized the situation by saying " we have been unable to put back the radioactive djinn in the bottle " (Pravda, February 11th, 1989,).

Finally, Moscow authorities disclosed maps in Pravda (March 20th, 1989), showing the general gamma-field pattern measured on 10th May 1986 with gamma dose readings for the Ukraine, Byelorussia and Russia. The dose rates used as basis for deciding on the early evacuation of people in 1986 were also given : prohibited zone for dose rates above 20 milliroentgen per hour (20 mR/h), evacuation above 5 mR/h, temporary evacuation of pregnant women and children between 3 and 5 mR/h. From these maps it is not clear why areas far away from Chernobyl (districts of Gomel, Mogilev and Bryansk) where gamma dose rates above 5 mR/h were recorded on 10th May 1986 were not included in the early evacuation plans. At the end of 1988 it was known that some villages in the Ukraine of Narodichi district close to the prohibited zone were about to be evacuated.

Concept of "Safe" living. Life time exposure : "35 rem per 70 years"

The legal definition of contaminated areas decreed by Soviet authorities consisted of areas with Cs137 deposition density above 1 curie per km². In 1989 more than 7 million people lived in these areas. (At the same time, in the UK, sheep were still forbidden for consumption, yet, their grazing pastures in highlands -Scotland, Cumbria etc.- were 2 or 3 times less contaminated than 1 Ci/km²). People were to be resettled from heavily contaminated areas with Cs137 levels higher than 40 Ci/km², some places are far away from Chernobyl.

Criteria for "relocation" : the "safe" living concept was worked out in September 1988 by the USSR authorities [17]. It was summarized in newspapers by the words " 35 rem per 70 years ". It is considered safe to live in a place where the dose accumulated during a 70 year-lifetime will not exceed 35 rem. If this dose exceeds 35 rem people had to be moved away and resettled in a new place. This life-long dose is calculated by radiological protection institutes, all of them depending on the Health Ministry of the USSR and therefore completely under control of Moscow authorities. Besides the dose received during the emergency phase (irradiation by the radioactive plume and ground deposits, inhalation of radioactive particules and aerosols, ingestion of contaminated food) the lifetime dose has to include the dose to be received in the future by living in a given place of residence. Therefore, besides external dose due to radioactive deposits, the lifetime dose must include the effective committed dose in 70 years due to ingestion of Cs137-contaminated food. Hot particles (containing transuranic elements ) were not considered. All these calculations depend on models : life-style and diet, metabolism, etc.

If this calculated dose exceeded 35 rem, relocation had to be decided. (L. Ilyin, head of the Soviet radiological protection said " it is not an evacuation but a planned displacement of people ". In places where the life-long dose was supposed not to exceed 35 rem, a normal lifestyle could be resumed with consumption of local food and no further import of clean food.

This concept "35 rem per 70 years" (0,5 rem/year, or 5 millisievert/year) had to become law on January 1st, 1990. Its authors assured that it was in line with ICRP recommendations. Byelorussian scientists, at the top level of the Academy of Sciences have fought against this law and brought forward another concept, 7 rem in 70 years (0,1 rem/ year) while Ukrainian scientists proposed 10 rem. Among the pertinent arguments of Byelorussian scientists [17] let us just recall that, since its Statement from the 1985 Paris meeting, ICRP recommended a lifetime average annual dose of 1 millisievert (1 mSv =0,1 rem).

The World Health Organization Experts.

The dispute between Byelorussian and Moscow scientists was open to the public in March 1989, during long debates of the session of the Soviet of Byelorussia and needed afterwards a special session devoted to 35 rem per 70 years which took place at the Byelorussian Academy of Sciences in Minsk with the participation of three WHO experts. Besides M. Waight, (WHO secretary), appeared as WHO experts Dan Beninson, mentioned before, and Pr. P. Pellerin, the head of French Services of Radiological Protection (SCPRI). Let us recall that at the Copenhagen WHO meeting held on 6th May 1986, only a few days after the reactor had exploded, delegates of all European countries presented the dose-rates values recorded in their country when it was reached by the plume. France, represented by a delegate of Pr. Pellerin's Services did not give any precise value and indicated only : "low" [18]. One might question if it is for this reason that, some years later, WHO qualified Pr. Pellerin to intervene in the radiological protection of the Soviet population.

The WHO experts' report was published in Sovetskaya Byelorussia (11 July 1989) under the title : "Experts' point of view". WHO experts concluded that, " in post-accident situations, an exposure of 35 rem during a lifetime of 70 years was quite a conservative value, (...) This value was in agreement with international recommendations based on assessments of ionizing radiation health risks. (...) If asked to fix a limit on the lifetime cumulative dose they should have chosen dose-limits of 2 to 3 times 35 rem " [the underlining is mine].

The report disparaged those scientists opposed to the life-dose limit supported by Soviet authorities " (...) Scientists who are not well versed in radiation effects have attributed various biological and health effects to radiation exposure (...) These changes (...) are more likely due to psychological factors and stress ".

In short, everything is known about radiation health effects, first-hand observations made by local medical doctors had to be in line with widespread consensus. It is worrying to see how these experts are denying an obvious fact : the Chernobyl catastrophe has the very sad privilege of inaugurating a new "experiment" in the medical field. They are trying to close the only way to approach it, first and foremost, all biological and medical information has to be registered and taken into consideration.

At the end of July 1989, during the Byelorussian Parliament's session which adopted the evacuation plans, the Health minister of Byelorussia referred to the WHO report and declared that Byelorussian scientists who opposed the 35 rem lifetime dose were ignorant of radiation questions. (Reported by I. I. Lichtvane, Vice-president of Academy of sciences, Sovetskaya Byelorussia, 1st August 1989).

In Paris some people became upset. What was Pr. Pellerin doing in the Ukraine and in Byelorussia making a false statement that a lifetime dose of 35 rem was in conformity with international recommendations and suggesting even higher limits 2 to 3 times 35 rem which are outside the prescribed French regulation ? Was Pr. Pellerin, a civil servant of the health minister in charge of French radiological protection, no longer obliged to respect French law when he was representing WHO ? Five associations asked many questions to the French health minister but never received an answer [19].

Meanwhile, through information available in France and first-hand news from medical doctors and journalists coming back from the Ukraine and Byelorussia it became obvious that the population's health was worsening (thyroid gland disorders, immunodeficiencies etc.). The answer of Soviet authorities was : radiophobia. Later on demonstrations took place in Minsk.

September 1989 : letter from 92 Soviet experts to M. Gorbachev to enforce the "35 rem lifetime concept"

The French Group of Scientists for Information on Nuclear Energy (GSIEN) got a copy of this letter dated 14 th September, 1989 and sent to the President of the Supreme Soviet of the USSR with 92 signatures of top scientists " working in the medical and radiological fields and concerned by the situation created by the Chernobyl accident " [20].

They wrote : " At each step of its elaboration this concept has been accompanied by a systematic consultation and a careful appraisal of various international organizations such as IAEA, WHO, UNSCEAR, which looked at it from all its angles and have approved it ".

Some arguments developed in this letter which oppose Byelorussian and Ukrainian proposals of lifetime doses of 7 or 10 rem instead of 35 rem, seem to us very important " In the choice of the lifetime limit of 35 rem the National Radiological Protection Commission of the USSR has paid attention to the fact that the limit has to include the dose received in the past three years, and in some agglomerations this cumulative dose is already about half the recommended lifetime dose ". In addition, in some villages where the dose of 35 rem has already been reached or soon will be, the decision of resettlement was taken a long time ago but " for some incomprehensible reasons has not yet been carried out in practice ". Furthermore " (...) it must be kept in mind that, since the accident, in most agglomerations of the permanent control zone, this dose (7-10 rem) has already been reached or will be reached in the near future ". The authors invoked the deep psychological and health detriment that could be caused by the " [displacement] resettlement of hundreds of thousands of people (up to one million) (...). If this 7-10 limit is adopted as a criterion for resettlement the problem will appear for the inhabitants of many big towns and district centers ". They further added that it cannot be taken for granted that good medical care could be assured in case of " a plan of resettlement of one million people ". [The underlinings are mine].

Thus, at that time, hundreds of thousands of people, up to one million, would have needed to be resettled if the 7-10 rem lifetime dose had become law. The comparison of these figures with the number of people living in all areas submitted to radiation control brings out clearly that the one million people figure is consistent with the number of all inhabitants of radiation control zones where Cs137 ground deposition is above 5 Ci/km² (see annex).

One might wonder why, as years passed, official estimates of people's cumulative doses were shrinking away in contaminated areas, and ask if this could not be the result of tampering with data, and readjusting measurements and models ...[20].

"The international Chernobyl Project". ICP Report.

In October 1989 the USSR government requested the IAEA to carry out an international experts' assessment of the health impact of Chernobyl and to evaluate the effectiveness of the protective measures taken by the Soviet Authorities. One goal of ICP was also to assist them and provide guidance on radiological protection subjects including their lifetime dose concept of 350 millisievert (35 rem) for "safe" living in areas affected by radioactive contamination. Besides Soviet experts, 200 specialists from 25 countries and 7 multinational organizations (IAEA, UNSCEAR, WHO, EEC etc.) participated in the Project.

The final ICP report was delivered at the international IAEA meeting in Vienna (21-24 May 1991) [21]. It was concluded that no health disorders could be attributed directly to radiation exposure. The ICP experts' estimates of both internal and external doses for the surveyed contaminated settlements were lower by a factor of 2 to 3 than the values officially reported by Moscow health authorities.The representatives of Byelorussia and the Ukraine have publicly demonstrated their disagreement.

The introduction emphazised the fact that the USSR government had already benefited from international assistance. Mentioned above, the team of WHO experts was first sent there in June 1989. Then the League of Red Cross and Red Crescent Societies which both came to the same conclusion as WHO : psychological stress and anxiety were causing physical symptoms. The International Chernobyl Project reached the same conclusion.

Concerning the safe lifetime dose of 35 rem for relocation, " the protective measures taken or planned for the longer term, albeit well intentioned, generally exceed what would have been strictly necessary from a radiological point of view. The relocation and foodstuff restrictions should have been less extensive ". As regards the social cost of relocation policy " (...) due account has not been taken by the authorities of the many negative aspects of relocation (...) ". And also, " In applying a lifetime dose criterion for relocation it is not appropriate to take into account of past doses ".

Some special points : all examined chidren were found in good health. Concerning thyroid gland disorders, no abnormalities in thyroid hormones. No statistically significant difference was found for any age group between surveyed contaminated settlements and surveyed settlements used as controls. Thyroid nodules were extremely rare.

Concerning neoplasms " The data did not reveal a marked increase in leukaemia or thyroid tumours since the accident ; however (...) the possibility of an increase in the incidence of these tumours cannot be excluded. Only hearsay information relating to such tumours was available ". Hearsay information ? The 1990 incidence of thyroid cancer in children was already 20 times the pre-Chernobyl incidence [22] and that year Pr. Demidchik had operated upon 29 children for thyroid cancer (59 in 1991 and more and more after).

No information was given about immunological deficiencies observed in children. No mention of the increase of chromosome aberrations. " No statistically significant evidence of an increase in incidence of foetal anomalies as a result of radiation exposure ". Quite a strong assertion when compared with the results which will be published by G. J. Lazjuk [23][24].

Some issues were not investigated at all : nothing about the health of the liquidators(5), of the early evacuees, no estimate of people's early doses received during the emergency phase.

A peculiar point : Pr. Pellerin provided 8 000 film badge dosimeters which were distributed to residents of selected settlements in contaminated areas : " For a two-month exposure period 90% of the results were under the detection limit (of 0.2 mSv) ". Let us point out that this detection limit corresponds roughly to a normal background dose (without extra-radiation) accumulated during the same two-month period. Therefore, no radiation above natural background was detectable in these selected villages ? Pr. Pellerin performed also whole body countings : the amount of incorporated caesium was found very low, as if "clean" food had been exclusively consumed in these selected contaminated villages. All information we got from contaminated radiation-controlled zones contradicts such an assessment. How can we trust it ? Let us recall a communiqué released by Pr. Pellerin's Services some days after the outset of the Chernobyl catastrophe : " [In France] the situation has come back to normal ", but without having been abnormal before ...

The "new" concept. Paris, April 1991 [25].

This concept, worked out by a team of Soviet scientists headed by academician S. Belaeyev, was presented in Paris and became law in May 1991. We will summarize it below.

- Since 1st January 1990, countermeasures have been implemented to ensure that the lifetime dose will not exceed 35 rem (350 mSv). It is supposed that they were crowned with success and therefore this limit of 35 rem has become useless.

- From now on past doses will not be taken into account. Only future averted doses should be considered for relocation (this point gives entire satisfaction to ICP experts). Doses received from 1986 to 1991 have to be considered only to improve living conditions but not for relocation. [Previously, according to the State Union republican programme of emergency measures for 1990-1992 on liquidation of the Chernobyl accident consequences (April 1990) relocation was compulsory for inhabitants of areas with Cs137 levels above 40 Ci/km², whereas the annual dose is likely to exceed 0.5 rem (5 mSv) and also for pregnant women and children from areas with Cs137 levels 15-40 Ci/km²]. From now on, no massive compulsory relocation is justified. Any additional resettlement should only be done on a voluntary basis.

- For 1991 and thereafter, the effective dose should not exceed 1 mSv/year (0.1 rem) which is the lower level of intervention. If annual doses exceed 1 mSv, radiological monitoring of environment and food, medical control, agrotechnical decontamination work [which proved unsuccessful in the past] etc. still go on. These measures must be optimised to limit average annual doses to 5 mSv in 1991 and to lower values afterwards.

The introduction of an annual dose limit of 1 mSv seemed to give satisfaction to Byelorussian and Ukrainian scientists. In fact, after having gained time and by ignoring past doses, the Soviet authorities have eliminated the possibility of new massive compulsory relocations. Relocation of all inhabitants of Cs137 contaminated zones above 15 Ci/km² (enacted by Republican parliaments) is no longer ascertained unless on a voluntary basis.

The implosion of the USSR and the emergence of independent Republics will aggravate the post-Chernobyl situation through food shortage and financial problems. By giving support to Moscow authorities, the intervention of WHO and international agencies in the management of the post-Chernobyl crisis has ruined the efforts of those scientists who tried to give better protection to the population living in contaminated areas. And for that we are responsible.

Health consequences in the aftermath of Chernobyl

Thyroid cancer and radioactive iodine

An abnormal increase of thyroid cancer in children was reported in Belarus in two scientific letters published in September 1992 in Nature [26] and met, at first, great scepticism among scientists working in the field of medical and radiological protection who denied that this increase could be the result of Chernobyl [27]. It was only after the data had been endorsed by well-known European scientists that the "hearsay" information (as written in ICP Report) was accepted as being true. It was the first time that some Western scientists (belonging to WHO !) gave support to medical doctors from the ex-USSR and they have to be thanked for their obstinacy. Thyroid cancer in children was also observed in the Ukraine and in Russia but with lower incidences than in Belarus. The number of thyroid cancer in adults increased enormously during the first 7 years after the accident but has since stabilized.

Experts' reconstructed thyroid doses are now on the rise. Who really got the millions of tablets of stable iodine as reported by Ilyin in 1987 ? The ICP Report concluded that the general response of the authorities had been broadly reasonable in the emergency phase [21]. But S. L. Belyayev conceded in 1991 that the countermeasures " have not always been taken in due time, not when they were really necessary and sometimes not completed " [25].

What about radionuclides other than iodine ?

Experts ensure us, at least in France, that apart from some 200 cancer deaths which will affect the "liquidators" in next decades, the only cancers due to Chernobyl will be thyroid cancers in children having been exposed to radioactive iodine. After surgery, everything is fine. Thus the Chernobyl health consequences will be limited essentially to psychological disorders.

In other words, does it mean that, aside from radioactive iodine, the cocktail of radionuclides (found in children's blood in the Ukraine and Byelorussia), caesium-137 and 134, ruthenium-106, strontium-90 etc. without forgetting transuranic elements like plutonium included in "hot particles", when ingested and inhaled will have no effect at all on the body ?

Thyroid cancer in children is a rare disease and its dramatic increase shortly after the accident gave clear evidence of its relation to radioactive iodine. But other radiation-induced cancers due to other radionuclides and to external exposure will only appear after latency periods of 10-50 years. If the follow-up of Chernobyl exposed populations in the next fifty years fails to show any statistically significant excess of cancer deaths it will not mean that this excess does not exist (especially if health statistics are under control of the management authorities). Even if the future Chernobyl radiation-induced cancer deaths are only a small fraction of the normal number of cancer deaths they might represent a total number of tens of thousands of deaths when applied to a huge population [13].

Furthermore, Chernobyl was followed by a morbidity increase implying some worsening of all functional systems which, in future, might be responsible for an increase of mortality for causes other than cancer. Please take note : In case of a severe nuclear accident, stable iodine will not protect people from radionuclides other than iodine and will not suppress the long term health consequences for the people exposed to the radioactive fallout.

Relocations after 1989

It is quite impossible to know exactly how many people have been moved away from the radiation-controlled zones and resettled compulsorily since 1989 and after the independence of Republics in 1991 because the number of voluntary relocations is never given. In 1993 the Ukrainian Minister of Chernobyl Affairs indicated 98 000 relocations since 1989 [13]. The Belarussian 1996 report of Ministry for Emergencies and Population Protection from the Chernobyl NPP Catastrophe Consequences indicated that the resettlement of the population is basically completed. 131 200 persons have been resettled [it seems that the 24 700 persons evacuated in 1986 are included]. No indication about the number of voluntary relocations.

An upper estimate of the number of resettled inhabitants for the three Republics of the ex-USSR might be around 300 000. This is far below the million people who should have been compulsorily resettled from all radiation-controlled zones and who scared Ilyin and his colleagues so much when they referred the matter to President Gorbachev in September 1989.

In Paris, Belyayev [25] asserted that it had been concluded from cost-efficiency or cost-benefit analysis in matters of countermeasures implementation, that relocation is uneffective in most cases. [But only managers and decision-makers evaluate costs, not the simple citizens. Belyayev did not give any precision about the price of a radiation-induced cancer or of other diseases]. Nevertheless he had admitted previously that " relocation could practically avert any further exposure dose " which is quite obvious.

These doses that could have been averted for the million inhabitants of areas with radiation control represent diseases, suffering and deaths for them and their progeny. And our experts have helped the central Soviet authorities to reduce the number of people to be relocated.

New ICRP recommendations in the event of a major nuclear accident

The ICRP made recommendations to protect the public in case of a severe nuclear accident in publication 40 (May 1984). In the early phase, the countermeasures are sheltering, stable iodine distribution, evacuation. Two levels of dose, the lower and upper levels, determine the dose range in which each countermeasure has to be implemented [28] : below the lower level of dose, countermeasure is not warranted, above the upper level its implementation should almost certainly have been attempted.

- Sheltering : whole body projected dose between 5 mSv (0.5 rem) and 50 mSv (5 rem).

- Administration of stable iodine : projected thyroid dose between 5 and 50 mSv.

- Evacuation : projected whole body dose between 50 mSv (5 rem) and 500 mSv (50 rem) and/or projected equivalent organ dose (thyroid, skin), between 500 and 5000 mSv.

Each step of decision-making requires cost-benefit optimisation. A countermeasure should be introduced " only when its social cost and risk is less than those resulting from further exposure ". Of course ordinary citizens are kept in ignorance of the subtle calculations of experts (with cost as a major parameter) who are discussing the price of their life. At that time ICRP did not consider long-lasting situations like Chernobyl's, where three years after the accident, lots of people still had to be moved away from contaminated areas and resettled.

After Chernobyl : obviously ICRP has drawn many lessons from Chernobyl disaster regarding dose limits for introducing countermeasures as shown by the new intervention levels recommended in 1992 (publication 63).

In the event of an accident the projected dose is calculated for each exposure pathway but the key concept for an intervention is the averted dose which is the dose saved by implementing a protective action. The " (...) implementation of a given protective action will be justified if its benefits, which include radiation detriment averted, are greater than its associated detriments , in terms of non-radiological risks associated with it, its financial cost and other, less quantifiable consequences such as social disruption ".

For the early phase, the worrying aspect of these recommendations is that precise values are given only for the almost always justified intervention levels.These justified upper limits correspond to the previous 1984 upper limits. They are in contrast to vague lower values of the range of optimised intervention levels, in which the optimised value has to be " not more than a factor of 10 lower than the justified value ". Averted dose estimates will depend on the moment at which a given countermeasure is introduced. Experts will "optimise" the costs to decide if this measure is worth implementing at that time. In case of a severe nuclear accident, authorities might be tempted to use the simple upper justified values as intervention levels. In fact, for ICRP, the only imperative requirement is to avoid serious deterministic effects.

As regards relocation which refers to the long-term removal of people from an affected area (like post-Chernobyl relocations after 1989) the justified level is 1 sievert (100 rem). But ICRP publication adds that " the justified level of averted dose for relocation might even be higher than this reference level ".

In line with its previous 1984 report which advocated optimised cost-benefit analysis, the new report specifies some monetary costs of implementation of a countermeasure strategy. For example relocation analysis requires to know the cost of one man-sievert, the collective dose unit related to the price of one person's life in case of a fatal radiation-induced cancer. In the table below are given the values for 3 parameters, for three types of countries : c is the cost of relocation per unit time (one month), alpha is the cost of unit collective dose (man-sievert), c/alpha is the derived value for the dose-rate (per month) at which relocation is optimised.

Type of country	c (US$ per man-month)	alpha (US$ per man-sievert)	c/alpha (mSv per month)
Rich developed Developed Developing	500 200 40	100 000 20 000 3 000		5 10 15

From the table it is possible to derive the price of life.The life of a developing country's inhabitant is worth 33 times less than of a rich developed country.The estimated price of a rich American's life is 2 million US$, the life of a poor Chinese only 60 000 US$ ! [4].

The dose-rate c/a value at which relocation is optimised is 15 mSv/month (1,5 rem/month) in a developing country, 3 times more than in a rich developed country. It is concluded that " the derived value for the dose rate at which relocation is optimised is about 10 mSv per month and is fairly robust around this figure ". The duration of such a relocation is not indicated. With 10 mSv/month, that is 1 rem/month, the Soviet 35 rem criterion would be attained in 3 years... Over 10 years, a cumulative dose of 120 rem would be of the same order of magnitude than the highest value recommended by Pellerin and Beninson " 3 times 35 rem". There's nothing surprising about that. Pellerin was a member of ICRP's Committee 4 which prepared the new recommendations while Beninson was the chairman of ICRP.

Finally, in the management of the Chernobyl nuclear crisis by the authoritarian Soviet power, 135 000 people were evacuated in 1986 and some 300 000 people were relocated after 1989. (Not enough, unfortunately, as shown previously). But who knows, a Western democratic government (like ours) might have imposed quite higher dose limits to avoid relocation of people and therefore left them to live in heavily contaminated areas...

The analysis of the intervention of Western experts in post-Chernobyl management demonstrates clearly that they gave unreserved support to the Central Soviet authorities and their relevant experts to the detriment of the population's health. The activity of Western experts has almost never been criticized either by the scientific community or by the intermediary bodies (medical profession, trade-unions, associations etc.) and medias.

Therefore we have to assume full and entire responsibility for the health consequences of the Chernobyl catastrophe. Furthermore, our experts have gained experience through Chernobyl. Since then, they have brought in strictly economic criteria for the management of future nuclear crisis. One has to remember that the possibility of a severe nuclear accident with its trail of dramatic consequences cannot be ruled out on our own nuclear reactors.

November 1997

Bella Belbéoch is Secretary of the Groupement de Scientifiques pour l'Information sur l'Energie Nucléaire (group of scientists for information on nuclear energy) which edits a quarterly review La Gazette Nucléaire, 2 rue François Villon, 91400, France. Fax : 33160143496

(To be published in the Acts of the 2nd International Scientific Conference on Consequences of Chernobyl Catastrophe Health and Information : From Uncertainties to Interventions in the Chernobyl Contaminated Regions, Geneva, 13th and 14th November 1997, Centre Universitaire d'Écologie Humaine et des Sciences de l'Environnement, Geneva, Switzerland).

Notes

(1) After independence in 1991, the Byelorussian SSR became the Republic of Belarus.
(2) Zones of periodic radiation control, Cs137 ground deposition 5 to 15 Ci/km2 (185 555 kBq/m2) zones of permanent, strict radiation control, Cs137 ground deposition > 15 Ci/km2.
(3) ICRP publication 26, 1977.
(4) The reported average infant thyroid dose was 4.3 milligray (4.3 mGy) in Byelorussia and 26 mGy in the most affected regions of Northern Ukraine. It will be clear that these values were completely wrong when thyroid cancer in children shows up in Byelorussia.
(5) More than 800 000 people, workers and soldiers, were brought into the region for accident management and recovery work to mitigate (liquidate) the consequences of the accident.

References

[1] Gazette Nucléaire n96/97, Juillet 1989. Dossier Tchernobyl trois ans après.

[2] AIEA. INFCIRC/380 Vienne, 25 Juillet 1990.

[3] USSR State Committee on the utilization of nuclear Energy : The accident at the Chernobyl nuclear plant and its consequences. Information compiled for the IAEA Expertí Meeting, 25-29 August 1986, Vienna.

[4] The collective dose, in man-sievert units, is the product of the total number of persons by one person's average dose in Sv. The number of the fatal radiation-induced cancers is derived from the product of the collective dose by the risk factor. In 1977 (ICRP 26) the fatal cancer risk factor was 1.25% per sievert. (125 fatal cancers will result from a dose of 10 000man-Sv. In 1990 (ICRP 60) it increased to 5%/Sv (500 fatal cancer will result from 10 000 man-Sv). If a collective dose of 1 man-Sv costs 100 000 US$, the price of 1 life is 2 million US$ (100 000 US$ : 0.05) but it seems that this price represents the social cost of one death and not the price of one's life which, evidently, has no price.

[5] Science, Sept. 12, 1986, vol. 233.

[6] Commission des Communautés Européennes. Líaccident nucléaire de Tchernobyl et ses conséquences dans le cadre de la communauté européenne, COM (86) 607, Oct. 1986.

[7] Nucleonics Week, May 10, 1990, p. 3.

[8] A. Moiseev, Analysis of the radiological consequences of the Chernobyl accident for the population in the European part of the USSR. WHO Consultation on Epidemiology related to the Chernobyl Accident, 13-14 May 1987, Copenhagen.

[9] Libération 4 nov. 1987.

[10] L. A. Ilyin, O. A. Pavlovskij Radiological consequences of the Chernobyl accident in the Soviet Union and mesures taken to mitigate their impact, IAEA Bulletin 4/1987.

[11] L. A. ILíIN The Chernobyl experience in the context of current radiation protection problems Proceedings of an international conference, Sydney 18-22 April 1988, Radiation Protection in nuclear energy, vol. 2 p. 363.

[12] UNSCEAR Report to the general Assembly 1988 Sources, effects and risks of ionizing radiation. The USSR collective committed effective dose equivalent is 226 000 man-Sv.

[13] Bella et Roger Belbéoch Tchernobyl une catastrophe Editions ALLIA, Paris 1993.

[14] Sobecednik, n17, Avril 1989, in Gazette Nucléaire n96/97 (1989)

[15] Gazette Nucléaire n84/85, Janvier 1988, p. 26

[16] Pravda Ukrayini, 5 and 15 July 1989. Maps in [17] and [13].

[17] Gazette Nucléaire n100, Mars 1990. Dossier Gestion post-Tchernobyl p. 16.

[18] Chernobyl reactor accident. Report of a consultation, 6 May 1986, WHO, Copenhagen.

[19] Gazette Nucléaire n101/102 Mai 1990 p. 32

[20] Gazette Nucléaire n109/110 Juin 1991. Dossier Tchernobyl 5 ans après (22 pages).

[21] The International Chernobyl Project. An Overview. Assessment of radiological consequences and evaluation of protective peasures. Report by an international Advisory Commitee, May 1991.

[22] Dr. Marie-Hélène Montaigne, Association Avicenne, Ronchain, France.

[23] G.I. Lazjuk et al. Radiation Protection Dosimetry vol. 62, n1/2 (1995) p. 71-74 Frequency of changes of inherited anomalies in the Republic of Belarus after the Chernobyl accident

[24] Gazette Nucléaire n157/158, Mai 1997. Dossier Tchernobyl 11 ans après (12 pages).

[25] S. T. Belyayev, V. F. Demin Les conséquences à long terme de Tchernobyl, les contre-mesures et leur efficacité. Actes de la conférence internationale les accidents nucléaires et le futur de líénergie. Leçons tirées de Tchernobyl. 15-16-17 Avril 1991, Paris.

[26] Scientific Correspondence Thyroid cancer after Chernobyl, Nature, 3 Sept. 1992, vol. 359 V. S. Kazakov, E. P. Demidchik, L. N. Astakhova, p. 21

K. Baverstock, B. Egloff, C. Ruchti, D. Williams, A. Pinchera, p. 21-22

[27] B. Belbéoch, En Biélorussie : cancers de la thyroïde chez les enfants

Gazette Nucléaire n 119/120, Août 1992.

[28] M. Genesco, private communication, 28/2/1989. At that time this authorized officer from the state-financed civilians rescue organization said that, in the emergency phase, if the projected dose could exceed the lower level of a countermeasure, this countermeasure should be implemented.

Books recommended :

Zhores Medvedev, The legacy of Chernobyl, Basil Blackwell, Oxford, 1990.

Permanent People's Tribunal, IMCC, Chernobyl, Vienna, 12-15 April 1996. (International Peace Bureau 41 rue de Zurich, 1201, Geneva, Switzerland).

Annex

 

Population living in legally contaminated areas in the Ukraine, Byelorussia and Russia (Cs137 > 1Ci/km²)