published by WISE News Communique on April 10, 1996




Contents Introduction 1 2 3 4

4. Health consequences of Chernobyl


Introduction

Of all countries, Belarus was affected the most by the Chernobyl catastrophe: 70 percent of all released radioactive substances from Chernobyl fell on its territory. The Belarus border is only 10 km north of the Chernobyl reactor. Practically the whole territory was heavily contaminated by radionuclides. More than 1.8 million people are still living in heavy polluted territories. The radiation dose they receive on average amounts to 15 mSv (milliSievert) a year.1 That is more than forty times the most recent ICRP radiation limit (1991) which is: 0.4 mSv/yr! The parliament declared the entire country a zone of ecological calamity. Around Gomel, close to Chernobyl, and also in regions within a distance of 140 km, there are very high radiation values. Less areas in Ukraine and Russia were heavily contaminated than in Belarus. Except in the evacuation zone around Chernobyl, agriculture goes on as before, even in heavily polluted regions. The private food production, which provides more than fifty percent of total food consumed, is not controlled at all. People in contaminated regions have a 30 percent higher rate of illness than elsewhere. 2 Ten years after Chernobyl, air, water and food contain still too high levels of cesium, strontium, plutonium and americium. Food items, especially milk, meat and mushrooms have accumulated high quantities of these four radioactive substances, far above Western radiation levels. In some areas, thyroid cancers among children have increased 200-fold since 1986.3

The source term

One of the most important and influential factors for the consequences of the Chernobyl catastrophe is the so-called 'Source Term', which refers to how much radioactivity was released from the exploded and burning reactor. The Russians and the IAEA declared shortly after the explosion that about 50 million curies of radioactive substances, plus another 50 million curies of rare and noble gases were released.4 (One curie is 37 billion becquerels). Even at that time, given the Russian habit of utmost secrecy especially in nuclear matters, many people doubted if these figures were true. Estimates of eight to forty five times as much radioactive emission were made, but ignored or denied.5 Scientists at the US Lawrence Livermore National Laboratory (LLNL) calculated that about 50% of all radioactivity was released. Starting from a total core inventory of 9 billion curies, that means that 4.5 billion curies were released.6,7,8 In the past ten years, many studies have been made. A consensus has been reached that the original Soviet figures were much too low. It is possible to calculate from data given in a booklet, published by the Nuclear Energy Agency Committee (NEA) of the Organization for Economic Cooperation and Development OECD9 that current estimates of released radionuclides are much higher than the estimates given by the Soviets in 1986 and in 1990. The estimated maximum release of a group of twenty important radionuclides totalled a staggering 12,536 PBq (Petabecquerels) or 340 million curies. This is at least seven times as great as the Soviet estimate. These NEA figures are still rather conservative. Future research will reveal whether the actual release of radionuclides was higher.
30 million still at risk
More than 30 million people could be contaminated by radioactivity sweeping down rivers from the Chernobyl nuclear power station. Floods are carrying downstream radioactive waste dumped around the reactor ten years ago when it exploded and caught fire. The lake most contaminated by radioactivity from Chernobyl is 250 km (155 miles) from the site. Fish in the Russian Lake Kojanovskoe has radiation levels 60 times above European Union safety norms and all fishing should be banned, scientists claim. Reservoirs downstream from the damaged reactor provide drinking water for nine million Ukrainians as well as irrigation and fish for another 23 million.
Source: Reuter, March 21, 1996
The 190 tons of nuclear fuel in the core of the Chernobyl no. 4 reactor contained about 400 different radionuclides, with an estimated initial total radioactivity of 9000 million curies. 10 The radioactive release of this limited number of 20 isotopes is estimated in the NEA study at more than six times the initial Russian estimate of total release of all radioactive isotopes. It is therefore sure that the total release of all radioactive isotopes is much more than the 339 million curies from twenty isotopes.

The World Health Organization (WHO) estimates that Chernobyl released 200 times as much radioactivity as the Hiroshima and Nagasaki explosions put together.11 An official report of Belarus published in 1995, however, still downplays the radioactivity released from Chernobyl. It mentions a total release of only 1000 Pbq, or 27 million curies12, twelve times less than the NEA-released data for only twenty radionuclides. (see Table) Why so much attention for the so-called 'source term' discussion? Most estimates of the health and ecological impacts until now were based on the lower Russian figures of 50 million curies released from Chernobyl. These health effect estimates are therefore much too low. When estimates of health consequences are based on the newer and much higher release data, they will turn out much higher too. The facts confirm this. Already in 1989 and thereafter, more and more information was gathered about greatly increased numbers of child thyroid cancers in the most affected areas in Belarus, Ukraine and Russia.

SOURCE TERM

Current estimate of radionuclide releases during the Chernobyl accident

Core inventory on 26 april 1986 Total release during the accident
Nuclide Half-life Activity (PBq)* Percent of inventory Activity (PBq)
Xenon-133 5.3 d 6500 100 6500
Iodium-131 8.0 d 3200 50-60 1600-1920
Cesium-134 ** 2.0 yr 180 20-40 36-72
Cesium-137 ** 30 yr 280 20-40 56-112
Tellurium-132 78.0 h 2700 25-60 675-1620
Strontium-89 52.0 d 2300 4-6 92-138
Strontium-90 28.0 yr 200 4-6 8-12
Barium-140 12.8 d 4800 4-6 192-288
Zirconium-95 1.4 h 5600 3.5 196
Molybdenum-99 67.0 h 4800 > 3.5 > 170
Ruthenium-103 39.6 4800 > 3.5 > 170
Ruthenium-106 1.0 yr 2100 > 3.5 > 74
Cerium-141 33.0 d 5600 3.5 196
Cerium-144 285 d 3300 3.5 116
Neptunium-239 2.4 d 27000 3.5 945
Plutonium-238 86 yr 1 3.5 0.035
Plutonium-239 24400 yr 0.85 3.5 0.03
Plutonium-240 6580 yr 1.2 3.5 0.04
Plutonium-241 13.2 yr 170 3.5 6
Curium-242 163.0 d 26 3.5 1
Total   73550   11033-12536
* PBq=one million times a billion Becquerel=27,027 Curie; 1 Curie=37 billion Becquerel;
** Acording to A.R.Sich 60-80% of all cesium was released. (The Chernobyl Accident Revisited: Source Term Analysis and Reconstruction. MIT, 7/1/94)
Source: Nuclear Energy Agency: 'Chernobyl, Ten Years On', nov.'95, p.29.


Lies on health consequences

In 1991, the IAEA dared to report that there were no serious consequences from Chernobyl: only 32 deaths; no perceived increase in mortality in the affected population; the main impact on health being of a psychological nature. The report was heavily criticized, because it was based on too little evidence, namely, on restricted data from the Russian officials (data from two villages) from the year 1990.
" After six months duty we are menatally tired. Physically, there wasn't much to complain about. Men with bigger health problems had been sent back by that time and at least I felt myself more fit with my lost weight than in the last ten years. What had to come - if it had to - would come later. But our mind was tired of the continuous, relentless tension, lack of knowledge and living style that was rationally unacceptable. Even just a couple of days ago one young fellow lost his mind in the lead battalion, walked barefoot between the tents and talked completely noncomprehensively as if he were from another world.. "

Source:Tiit Tarlap, Chernobyl 1986, Memories of an Estonian Cleanup Worker.
Moreover, given the latency of 10 years or more for thyroid cancers, it was not yet possible to observe thyroid cancers. All liquidators and evacuated people were left out in the study. The IAEA knew this. It was probably also not so naive as to believe the Russian data were sufficient to draw conclusions from. The conclusion must therefore be that the IAEA deliberately tried to mislead and deceive the public.

In 1994, Dr. M. Rosen, director of the IAEA, claimed that the health effects to the surrounding population would be sufficiently small, so small as not to be discernible through epidemiological studies, except for the apparent, expected and regrettable increase in thyroid cancer among children.13

Soon after the catastrophe, it became clear that the USSR had intentionally withheld crucial information, for several reasons:

  • to prevent panic and opposition (by downplaying the consequences to their own population);
  • to protect the people in charge by hiding the truth;
  • to protect the nuclear industry.
According to a nuclear industry magazine, the Soviet Union's suppression of information vital to understanding the causes and consequences of the accident looks 'more like a matter of deliberate deception'.14 Some examples:
  • Six pages concerning radioactivity released in Belarus were removed from the official report, just prior to the August 1986 IAEA meeting;
  • Several pages detailing large quantities of radionuclides deposited 100 km or farther northeast of Chernobyl in the Briansk Oblast of Russia were removed from the report;
  • Physicians in Ukraine and Belarus were forbidden to mention radiation in their diagnoses;
  • All health records of the liquidators of the consequences of the accident were 'missing' (since the collapse of the USSR, these data slowly surfaced);
  • Publication of 'unauthorized' measurements of radioactivity were forbidden and even in 1990 still were forbidden;
  • The KGB confiscated dosimeters in the possession of physicians and private individuals;
  • Appeals by private individuals in Belarus to children not to drink milk in the first weeks of May 1986, were stopped 'for fear they might cause panic'.15
On account of the above, it is clear that the authorities were guilty of causing more thyroid cancers among children.


"The main activity there (at the plant itself) had to do with waiting. Men worked in little groups (on the roof of the third reactor even in pairs) and the rest were waiting for their turn in the hallway leading to the roof, or for the day end if they had already been there. Those, whose turn it was, reveived the lead protective clothing, gloves and glasses reminding those of the metalworkers. On command they went to the roof, grabbed some piece of debris and threw it down across the edge or in front of a robot-like mechanism..."

Source:Tiit Tarlap, Chernobyl 1986, Memories of an Estonian Cleanup Worker.

Inexplicably high number of thyroid cancers

Thyroid cancer experts are becoming more and more concerned or even distressed over the extraordinary increase in recent years in the number of thyroid cancers among children and liquidators. Thyroid cancer is caused by radiation from iodine-131. As almost 100 percent of all iodine-131 present in the core of Chernobyl's ill-fated reactor 4 was released, people in the contaminated regions were exposed to high doses just by breathing. Although the half-life of iodine-131 is only eight days, the radioactivity was so high that thyroid glands, especially of children and the unborn, were severely damaged. The damage was done during the first forty days after the catastrophe.

There is no question any more about the increase of thyroid cancers, nor much discussion about the total numbers. Although the latency time for thyroid cancer is normally 10-15 years, the number of thyroid cancers began to rise in 1990 - just four years after the accident.16 Studies of Japan's A-bomb survivors show that the incidence of thyroid cancer started to increase significantly ten years after the A-bomb explosions.17

The 10- to 100-fold increase in child thyroid gland cancers in 1994 compared to pre-Chernobyl figures in the most affected areas in Belarus, Ukraine and Russia is much higher than any scientist had expected. In the most contaminated area, Gomel in southern Belarus, the number of children with thyroid cancer has increased every year since 1986 from less than 1 per million before 1986 to more than 200 per million in 1994. Since 1986, doctors have thus far diagnosed 680 cases of thyroid cancer in children, ten of whom have died.18

Even a release of radioactive Iodium-131 ten times bigger than that reported by the Russians in 1986 cannot explain this 100- to 200-fold increase in thyroid cancers. All the more so because scientists did not expect this big increase, and especially not so soon. The pattern of cancers is also very much different from the patterns known till now. There are four alarming developments:19

  1. There are much more thyroid cancers than expected;
  2. They appear much sooner than expected;
  3. The distribution over girls and boys is else than expected.
  4. The cancers grow more quickly than expected.
The experts in this field have proposed several explanations, which cannot explain, however, all observed facts. A factor which can partly explain the abnormal growth of cancer is the fact that a big part of the population of Belarus and Ukraine suffered from goiter, which is caused by a shortage of iodine in the food. When a person has goiter, his thyroid gland takes up the available iodine much more efficiently.20 Another possible partial explanation is the fact that the thyroid glands were exposed to very high radiation doses during a relatively long time. First via ingestion through breathing, later through the drinking of contaminated milk. A report of the UNSCEAR (United Nations Scientific Committee on Sources and Effects of Atomic Radiation) published in 1994 uses a risk-coefficient to express the consequences of radiation on the thyroid gland. If this factor is known and also the amount of radiation, you can calculate theoretically the expected number of thyroid cancers.21 It is gruesome that the number of thyroid cancers in the contaminated areas is ten times higher than expected on the basis of these calculations. Higher numbers in the near future are expected.22


Long-term consequences

Nine million people (2.5 million in Belarus, 3.5 million in Ukraine, 3 million in Russia) still live in contaminated areas, still eat radioactive food, drink radioactive liquids, breath radioactive air. The consequences will be felt for centuries. 23 Eighty days after Chernobyl, the iodine-131 totally disappeared through radioactive decay. Cancers caused by it, however, will occur for many more years in the future.

From a reading of Table II (which is, sorry!, only aviable in the printed version), it becomes clear that cesium-137, which has a half-life of 30 years, poses the greatest danger. This is so because cesium-137 will stay in the food-chain and will not disappear completely before 300 years. Thus, not only the present generation will suffer from its radioactivity, but also many future generations.

Radiation not only triggers an epidemic of cancers - thyroid, lung, skin breast and stomach cancers - but also increases the incidence of strokes, heart attacks and liver disease, the weakening of the immune system, as well as damaging the brains of babies in the womb.

After the A-bombs on Hiroshima and Nagasaki, it took 20 to 30 years for increases in breast, lung, gastric and colon cancers to be detected. Doctors in Belarus now claim that the incidence of these cancers has already risen.24

The authorities consider arable land as 'clean' if its contamination density is lower than 37,000 Bq (37 kBq) cesium-137/m2. However, through accumulation by mushrooms, contamination levels, higher than permissible levels, occur already at a contamination level of 7.4 kBq/m2. Far worse, agricultural production nowadays is permitted in territories with more than 1480 kBq/m2.25

Radiation doses are higher than calculated because the contamination level of food is higher than officially assumed. Privately produced foodstuff is almost not controlled at all, because this is not marketed. Hence, highly contaminated food is not destroyed, but consumed. Due to the economic crisis, more and more food is produced privately. This practice is dictated by the shortage of money, which prevents the people from buying uncontaminated food for humans and fodder for cattle from elsewhere.

The main dose-forming factors for internal radiation of the population, including persons not living on the contaminated territories, are the radionuclides (cesium, strontium, plutonium and americium) in milk and meat products, with concentrations several hundred times higher than pre-accident levels and often above the permitted levels. These radionuclides in the soil, plants, water and air will stay in the food chain for hundreds of years.

In the Gomel region, 23% of the children received doses which exceeded 1000 mSv, very high compared to the ICRP limit of 0.4 mSv/yr. The second highest doses - up to 500 mSv - were absorbed by the 800,000 liquidators and by the 135,000 people from the evacuation zone, who were mostly evacuated after up to 10 days. After five years, more than 50% of the liquidators contracted some sort of disease.26 The frequency of thyroid diseases among them increased 40 times.

The radiological situation in Belarus is determined by the heavy contamination of a quarter of its territories and the presence of radionuclides in the natural and agricultural ecosystems. These cause a plurality of ways of external and internal irradiation of the population and will jeopardise its health for centuries. The permissible level of radioactive contamination of fields and food is much higher than in Western countries. The same applies for the permitted limits of irradiation doses for the public. In Belarus the public irradiation dose limit is 1 milliSievert (mSv) per year. This limit is surpassed however in many contaminated regions, where people have accumulated doses of up to 1000 mSv. The most recent ICRP dose limit is 0,4 mSv/yr. In relatively 'safe' regions in Russia, internal irradiation doses of 5-25 mSv/yr were measured in 1991/92. About 30-85% of the adult population is exposed to such irradiation yearly, in addition to the external irradiation they have received since 1986. When the internal irradiation (mainly from food) is added to the external, cumulative doses since 1986 already exceed the average lifetime 1000 mSv level, the so-called Ramzaev's level.27

It is sure that the incidence of thyroid and other cancers, which have a latency period of 10 years or more, will rise further in the next five to ten years. It is strange that health consequences of the Chernobyl catastrophe other than cancers are not mentioned in most reports. Among the liquidators, general morbidity has risen too. The funds for adequate treatment are however not available even in the most polluted country, Belarus, where 70% of all radioactivity from Chernobyl fell, nor in other heavily contaminated regions in Ukraine and Russia.

Up to now, one still hears talk that there were 'no more deaths because of radioactivity' and that Chernobyl caused 'mainly psychological effects, the so-called radiophobia'. These must be seen as nonsense and lies.

Better studies on the long-term health effects, based on the more accurate released data, must be made, together with studies on how to treat the affected people in the best way. The biggest hurdle in doing this is the grim economic and financial situation in the most affected countries: Belarus, Ukraine and Russia. They simply cannot afford to pay for the decontamination of the most polluted areas, the needed medical treatment of the victims or for uncontaminated food for the nine million people still living in the contaminated areas, who are forced to eat contaminated agricultural products from their own gardens and fields, to drink contaminated water and milk, to breath contaminated air.


Sources:

  1. Environmental Policy Review (Israel), Winter 1995; V.L.Adamovich, "Erroneous Approach Or Deafening Silence?" p.49
  2. Otto Hug Strahleninstitut (FRG), Nov. 1995; "Folgen der Tschernobyl-Katastrophe - Aktuelle Informationen" (Consequences of the Chernobyl Catastophe - Actual Information) p.4
  3. New Scientist (UK), 9 Dec. 1995; "Will it get any worse" p.14
  4. Nuclear Energy Agency, Febr. 1996; "Chernobyl Ten Years On. Radiological and Health Impact" p.28
  5. Nieuwe Beta (NL), 4 April 1987; "Lozingen uit Tsjernobyl 8 maal groter dan gemeld" (Release from Chernobyl 8 times bigger than stated) p.8,9
  6. Science, 13 June 1986; p.1331-33
  7. KfK Nachrichten (FRG), no. 3, 1986; H. Albrecht: "Zum Ablauf von Kernschmelzen-Unfaellen: Spaltprodukt-Freistellung, Source-Term und Tschernobyl-Emission"(To the End of Meltdown Accidents: Radioactive Releases, Source Term and Chernobyl Emissions) p. 150-157
  8. Gesellschaft fur ReaktorSicherheit (GRS), (FRG), Febr. 1987; "Neuere Erkenntnisse zum Unfall im Kernkraftwerk Tsjernobyl", (Newest Insights in Accident in Chernobyl Nuclear Reactor) p.39
  9. Nuclear Energy Agency, Febr. 1996; "Chernobyl Ten Years On. Radiological and Health Impact" p.28
  10. KfK Nachrichten (FRG), no 3 1986; H.Albrecht: "Zum Ablauf von Kernschmelzen-Unfällen: Spaltprodukt-Freistellung, Source-Term und Tsjernobyl-Emission" (To the End of Meltdown Accidents: Radio-active Releases, Source Term and Chernobyl Emissions) p.156
  11. New Scientist (UK), 9 Dec. 1995; "Will it get any worse" p.14
  12. The Republic Of Belarus, Nov. 1995; "Nine Years after Chernobyl. Situation, Problems, Action" p.10
  13. Anumukti (India), Oct/Nov. 1995; "Trivialising Risks" p.8
  14. Nuclear Engineering International, May 1993, p.5
  15. Nuclear Safety, Jan/June 1994; A.R.Sich: "Chernobyl Accident Management Actions" p.21-24
  16. World Health Organisation, 1995; "Health Consequences Of The Chernobyl Accident. Summary Report." p.21-24
  17. Belarus, 1995; A.E.Okeanov et al., "Health Effects Of Radiation Exposure" p.5
  18. New Scientist (UK), 9 Dec.1995; "Will it get any worse" p.14
  19. Cancer, no 2 1994; Y.Nikiforov, D.R. Gnepp, "Pediatric Thyroid Cancer after the Chernobyl Disaster" p.748-766
  20. UN, Department of Humanitarian Affairs News, Sept./Oct. 1995; K.F.Baverstock, "Who calls for more aid to help child thyroid victims"p.9-11
  21. Strahlentelex (FRG), 7 Dec. 1995; H.Ziggel, "Schilddrusenkrebs nimmt schneller zu als erwartet" (Thyroid cancer increases faster than expected) p.1-4,9
  22. Lancet (UK), 23 July 1994; T.Ito et al., "Activated RET Oncogene in Thyroid Cancers of children from areas contaminated by Chernobyl accident" p.259
  23. Otto Hug Strahleninstitut (FRG), Nov. 1995; "Folgen der Tschernobyl-Katastrophe - Aktuelle Information" (Consequences of the Chernobyl Accident - Actual Information) p.3
  24. New Scientist (UK), 9 Dec. 1995; "Will it get any worse" p.14
  25. The Republic Of Belarus, 1995; "Nine Years after Chernobyl. Sitution, Problems, Action" p.52
  26. The Republic Of Belarus, 1995; "Nine Years after Chernobyl. Sitution, Problems, Action" p.31
  27. Environmental Policy Review (Israel), Winter 1995; V.L.Adamovich, "Erroneous approach or deafening silence?" p.44-50.
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