This article contains pictures from the original incident
and commentary from:
Ten Years of the Chernobyl Era, Yuri Sheerbak Sci Am Apr 96
The total amount of radioactivity released will never be known, but the official Soviet figure of 90 million curies represents a minimum. Other estimates suggest that the total might have been several times higher. It is fair to say that in terms of the amount of radioactive fallout-though not, of course, the heat and blast effects-the accident was comaparable to a medium-size nuclear strike. In the immediate aftermath of the explosion and fire, 187 people fell ill from acute radiation sickness; 31 of these died.
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Most of these early casualties were firefighters who combated the blaze. The destroyed reactor liberated hundreds of times more radiation than was produced by the atomic bombings of Hroshima and Nagasaki. The intensity of gamma radiation on the site of the power plant reached more than 100 roentgens an hour. This level produces in an hour doses hundreds of times the maximum dose the International Commission on Radiological Protection recommends for members of the public a year. On the roof of the destroyed reactor building, radiation levels reached a frightening 100,000 roentgens an hour. The human dimensions of the tragedy are vast and heartbreaking. At the time of the accident, I was working as a medical researcher at the Institute of Epiderniology and Infectious Diseases in Kiev, some 60 miles from the Chomobyl plant. Sometime on April 26 a friend told me that people had been arriving at hospitals for treatment of burns sustained in an accident at the plant, but we had no idea of its seriousness. There was little official news during the next few days, and what there was suggested the danger was not great. The authorities jammed most foreign broadcasts, although we could listen as Swedish radio reported the detection of high levels of radioactivity in that country and elsewhere. I and some other physicians decided to drive toward the accident site to investigate and help as we could. We set off cheerfully enough, but as we got closer we started to see signs of mass panic. People with connections to officialdom had used their influence to send children away by air and rail. Others without special connections were waiting in long lines for tickets or occasionally storming trains to try to escape. Families had become split up. The only comparable social upheaval I had seen was during a cholera epidemic. Already many workers from the plant had been hospitalized. The distribution of the fallout was extremely patchy. One corner of a field might be highly dangerous, while just a few yards away levels seemed low. Nevertheless, huge areas were affected. Although iodine 131 has a half-life of only eight days, it caused large radiation exposures during the weeks immediately following the accident. Strontium 90 and cesium 137, on the other hand, are more persistent. Scientists believe it is the cesium that will account for the largest radiation doses in the long run. All told, well over 260,000 square kilometers of territory in Ukraine, Russia and Belarus still have more than one curie per square kilometer of contamination with cesium 137. At this level, annual health checks for radiation effects are advised for residents. In my own country of Ukraine, the total area with this level of contamination exceeds 35,000 square kilometers-more than 5 percent of the nation's total area. Most of this, 26,000 square kilometers, is arable land. In the worst affected areas there are restrictions on the use of crops, but less contaminated districts are still under cultivation. The heavily contaminated parts of Ukraine constitute 13 administrative regions (oblasts). In these oblasts are 1,300 towns and villages with a total population of 2.6 million, including 700,000 children. Within about 10 days of the accident, 135,000 people living in the worst-affected areas had left their homes; by now the total has reached 167,000.
The medical consequences are, of course, the most serious. Some 30,000 people have fallen ill among the 400,000 workers who toiled as "liquidators," burying the most dangerous wastes and constructing a special building around the ruined reactor that is universally referred to as "the sarcophagus. " Of these sick people, about 5,000 are now too ill to work.
It is hard to know, even approximately, how many people have already died as a result of the accident. Pop ulations have been greatly disrupted, and children have been sent away from some areas. By comparing mortal ity rates before and after the accident, the environmen tal organization Greenpeace Ukraine has estimated a to tal of 32,000 deaths. There are other estimates that are higher, and some that are lower, but I believe a figure in this range is defensible. Some, perhaps many, of these deaths may be the result of the immense psychological stress experienced by those living E in the contaminated region. One medical survey of a large group of liquidators, carried out by researchers in Kiev led by Sergei Komissarenko, has found that most of the sample were suffering from a constellation of symptoms that together seem to define a new medical syndrome. The symptoms include fatigue, apathy and a decreased number of "natural killer" cells in the blood. Natural killer cells, a type of white blood cell, can kill the cells of tumors and virus-infected cells. A reduction in their number, therefore, suppresses the immune system. Some have dubbed this syndrome "Chornobyl AIDS." Besides having increased rates of leukemia and malignant tumors, people with this syndrome are susceptible to more severe forms of cardiac conditions as wefl as common infections such as bronchitis, tonsillitis and pneumonia. As a consequence of inhaling aerosols containing iodine 131 immediately after the accidt-nt, 13,000 children in the region experienced radiation doses to the thyroid of more than 200 roentgen equivalents. (This means they received at least twice the maximum reconnnended dose for nuclear industry workers for an entire year.) Up to 4,000 of these children had doses as high as 2,000 roentgen equivalents. Because iodine col. lects in the thyroid gland, these childr-have developed chronic inflammation of the thyroid. Although the inflammation itself produces no symptoms, it has started to give rise to a wave of cases of thyroid cancer.
The numbers speak for themselves. Data gathered by the Kiev researcher Mykola D. Tronko and his colleagues indicate that between 1981 and 1985 before the accident-the number of thyroid cancer cases in Ukraine was about five a year. Within five years of the disaster the number had grown to 22 cases a year, and from 1992 to 1995 it reached an average of 43 cases a year. From 1986 to the end of 1995, 589 cases of thyroid cancer were recorded in children and adolescents. (In Belarus the number is even higher.) Ukraine's overall rate of thyroid cancer among children has increased about 10-fold from pre-accident levels and is now more than four cases per million. Cancer of the thyroid metastasizes readily, although if caught early enough it can be treated by removing the thyroid gland. Patients must then receive lifelong treatment with supplemental thyroid hormones. Other research by Ukrainian and Israeli scientists has found that one in every three liquidators-primarily men in their thirties-has been plagued by sexual or reproductive disorders. The problems include impotence and sperm abnormalities. Reductions in the fertilizing capacity of the sperm have also been noted. The number of pregnancies with complications has been growing among women living in the affected areas, and many youngsters fall prey to a debilitating fear of radiation. The optimists who predicted no longterm medical consequences from the explosion have thus been proved egregiousIY wrong. These authorities were principally medical officials of the former Soviet Union who were following a script written by the political bureau of the Communist Party's Central Committee. They also include some Western nuclear energy specialists and military experts. It is also true that the forecasts of "catastrophists"-some of whom predicted well over 100,000 cancer cases-have not come to pass. Still, previous experience with the long-term effects of radiation-much of it derived from studies at Hiroshima and Nagasaki-suggests that the toll will continue to rise. Cancers caused by radiation can take many years before they become detectable, so the prospects for the long-term health of children in the high-radiation regions are, sadly, poor. The,hushing up of the danger from radiation in Soviet propaganda has produced quite the opposite effects from those intended. People live under constant stress, fearful about their health and, especially, that of their children. This mental trauma has given rise to a psychological syndrome comparable to that suffered by veterans of wars in Vietnam and Afghanistan. Among children evacuated from the reactor zone, there has been a 10to 15-fold increase in the incidence of neuropsychiatric disorders. The catastrophe and the resulting resettlement of large populations have also caused irreparable harm to the rich ethnic diversity of the contaminated areas, particularly to the so-called drevly-any, woodland people, and polisbchuks, inhabitants of the Polissya region. Unique architectural features and other artifacts of their spiritual and material culture have been effectively lost as abandoned towns and villages have fallen into disrepair. Much of the beautiful landscape is now unsafe for humans.
The Ukrainian government, which is in a severe economic crisis, is today obliged to spend more than 5 percent of its budget dealing with the aftermath of Chornobyl. The money provides benefits such as free housing to about three million people who have been officially recognized as having suffered from the catastrophe, including 356,000 liquidators and 870,000 children. Ukraine has introduced a special income tax corresponding to 12 percent of earnings to raise the necessary revenue, but it is unclear how tong the government can maintain benefits at current levels.
Today the Chornobyl zone is one of the most dangerously radioactive places in the world. In the debris of the ruined reactor are tens of thousands of metric tons of nuclear fuel with a total radioactivity level of some 20 million curies. The radiation level in the reactor itself, at several thousand roentgens per hour, is lethal for any form of life. But the danger is spread far and wide. In the 30kilometer zone surrounding the reactor are about 800 hastily created burial sites where highly radioactive waste, including trees that absorbed radioisotopes from the atmosphere, has been simply dumped into clay-lined pits.
These dumps may account for the substantial contamination of the sediments of the Dnieper River and its tributary the Pripyat, which supply water for 30 million people. Sediments of the Pripyat adjacent to Chornobyl contain an estimated 10,000 curies of strontium 90, 12,000 curies of cesium 137 and 2,000 curies of plutonium. In order to prevent soluble compounds from further contaminating water sources, the wastes must be removed to properly designed and equipped storage facilities-facilities that do not yet exist.
Chernobyl Repairs New Scientist 97
SUNLIGHT streams through cracks in the sarcophagus that is meant to stop radioactivity leaking from the damaged nuclear reactor at Chernobyl in Ukraine. Scientists who have ventured inside the huge concrete box, which was hastily erected around the reactor after it exploded in 1986, even report seeing birds flying in and out of holes. But now the myriad cracks and holes could be plugged. An American company, Eurotech of La Jolla in California, has been given the go-ahead by the Ukrainian government to start testing a new foam spray at Chernobyl in the spring. The company says that 35 000 cubic metres of grey foam, made from silicon elastomers that are resistant to the effects of radiation, could be used to fill the sarcophagus and seal the hundreds of tonnes of hazardous radioactive debris inside. The foam, called EKOR, was developed by the Russian government's Kurchatov Institute in Moscow with financial backing from Eurotech. According to Eurotech's Randolph Graves, two types of foam could be used at Chernobyl: one that is stiff and sticky and another that hardens.
When the Dust
NS 10 Oct 98 20
RADIATION-induced conditions and tumours other than thyroid cancer have increased significantly in the former Soviet republic of Belarus since the accident at the Chernobyl nuclear plant in 1986, say local researchers. Many experts claim that the only significant health effect of the explosion was to increase by a factor of 200 the number of people contracting thyroid cancer. There have been 900 cases since 1990 in the region affected by fallout from Chernobyl, most of which is within Belarus. Chernobyl, in Ukraine, is less that 20 kilometres from the Belarussian border. An international conference on Chernobyl sponsored by the WHO and others, held in Vienna in 1996, concluded that there was "no consistent, attributable increase ... either in the rate of leukaemia or in ttic incidence of any malignancies other than thyroid carcinomas". This declaration deprived Belarus of much of the international aid it had hoped for. But Rose Goncharova of the Institute of Genetics and Cytology at the Academy of Science in Minsk, the capital of Belarus, has reanalysed data collected in 1996 for a national genetic monitoring programme. She found that since 1985, the number of reported cases of congenital malformations in children, such as cleft palate, Down's syndrome and deformation of limbs and organs, has increased by 83 per cent in areas heavily contaminated by fallout from Chernobyl, by 30 per cent in mildly contaminated regions and by 24 per cent in "clean" areas. All these congenital conditions have been linked to radiation damage in past research. Goncharova discounts another possible cause, toxic chemicals, because pollution has fallen significantly over the past 10 years. Goncharova's study is the first to quantify what local researchers have believed for years (see "Will it get any worse?" ( New Scientist, 9 December 1995, p 14). A conference in Minsk in March this year challenged the conclusion of the 1996 Vienna meeting, claiming that the Chernobyl catastrophe had caused many malignant tumours, congenital developmental malformations and other long-term consequences. "The existence of a serious radiation risk ... should be admitted." And at the Vienna conference itself, researchers from the Centre for Medical Technology in Belarus presented a study showing an increase in a wide range of tumours among the population living in Gomet, the most contaminated area in Belarus, Elisabeth Cardis from the International Agency for Research on Cancer in Paris, who presided over the session on longterm health effects at Vienna, is sceptical of Goncharova's conclusions, which are published in the proceedings of the Minsk conference. "It is likely that registration [of abnormalities] has been improving in recent years, which could lead to the observed increases." Chris Groner
Friday, 15 December, 2000, 11:22 GMT Chernobyl shut down for good
Chernobyl explosion in 1986 killed thousands of people Ceremonies are taking place in Ukraine to mark the closure of the ill-fated Chernobyl nuclear plant - more than 14 years after a reactor exploded in the world's worst civil nuclear catastrophe.
Ukrainian President Leonid Kuchma gave a nationwide television address before ordering the Chernobyl control room to press a button shutting down the last working reactor.
Shortly before closing the plant, Prime Minister Viktor Yushchenko told reporters: "Today Ukraine must understand that Chernobyl is a big tragedy for the world."
There was confusion on Thursday in the capital Kiev as parliament voted to postpone the closure until April 2001.
Angry Chernobyl workers staged protests as President Kuchma took foreign dignitaries including the premiers of Russia, Belarus and Georgia on a tour of the disaster plant.
An estimated 15,000 to 30,000 people have died as a result of the 26 April 1986 explosion at Chernobyl.
Ukraine has for years come under international pressure to close the Chernobyl but said it needed Western funding to provide alternative sources of energy.
Representatives from more than 10 countries including the United States were attending the closing ceremony.
"For the entire world, Chernobyl stands as a negative symbol that should have no place upon the earth," said President Kuchma.
"I want to reaffirm once again that we've taken the only right decision, from all points of view and first of all the moral one," he said.
"I believe certain forces do not show common sense, but engage in political games," the president said in response to last minute parliamentary calls to cancel the shutdown plans.
The European Union agreed to provide a total of nearly $1bn to help two replacement nuclear reactors in the former Soviet republic.
Funding plans attacked
But environmentalists Greenpeace International condemned the EU plans terming them as "utterly cynical".
The pressure group's nuclear expert Tobias Munchmeyer said Ukraine should instead meet its energy capacity needs through renewable sources and improving efficiency.
Greenpeace International also said the closure of the Ukrainian plant should be followed by shutdowns at similar plants in Russia and Lithuania.
"We cannot afford to wait another 14 years before the remainder are shutdown," said Mr Munchmeyer.
The pressure group said three million children require treatment as a result of the disaster.
The plant in north-west Ukraine was not only the site of the world's worst nuclear disaster but remains arguably the most vivid symbol of the legacy left after the Soviet Union collapsed almost nine years ago.
The area around the power station has witnessed gross freaks of nature in flora and fauna.
And experts say it will be unfit for human habitation for generations to come.