Chornobyl's impact on health, the environment and the economy
by David R. Marples
The following was delivered as the 31st annual Shevchenko Lecture on April 2, at the University of Alberta, David R. Marples is professor of history and director of the Stasiuk Program on Contemporary Ukraine (CIUS), University of Alberta, Canada. The Shevchenko Lecture was organized by the Canadian Institute of Ukrainian Studies and sponsored by the Ukrainian Professional and Business Club of Edmonton.
PART I
The Chornobyl disaster is a political event. It began in secrecy and today remains shrouded in controversy. There is no consensus over the results. Moreover, the situation has been made more complex by international studies and reports. There have been distortions of fact both by the "international scientific community" - as epitomized by the International Atomic Energy Agency (IAEA) and the World Health Organization (WHO) - and the general public, Ukrainian and Belarusian ministries, former clean-up crews and indeed the majority of people actively involved in assessment of or affected by radiation fallout from Chornobyl.
As the 10th anniversary approaches, one can see how the political aspects of Chornobyl have served to obscure truth.
On the one hand, the Ukrainian Ministry of Health issued a statement last year that there had been 125,000 deaths to date from Chornobyl. It took me several weeks of investigation before it became evident how such a figure was derived. In fact, it includes all the deaths in the areas of Ukraine contaminated by the accident regardless of cause, i.e., it encompasses so-called natural deaths. On the other hand, the recent conference of scientists in St. Petersburg and the report of the European Community (EC) on Chornobyl gave rise to several publicized statements, none of which in my view were accurate:
In turn, the situation has been complicated by the demands of the world and the Ukrainian nuclear industry, the fate of the Chornobyl plant itself, and the energy needs of independent Ukraine, which over four years has run up huge debts for imports of oil and gas from Russia and Turkmenistan. We will look at each of these questions in turn.
Radiation fallout
Over 450 different types of radionuclides were released by the Chornobyl disaster in the period between the early hours of April 26 and May 10, 1986, when the reactor was capped. Fallout occurred first over Belarus, the Baltic republics, Eastern Poland and Scandinavia, in addition to the Kyiv Oblast of Ukraine. After April 30 a change of wind direction brought considerable fallout into Ukraine and Russia. Affected especially in the former country were the Kyiv, Zhytomyr and Chernihiv oblasts, then the radiation spread south of Kyiv particularly into Kirovohrad and westward toward and beyond the Polish border.
The chief initial danger came from radioactive iodine, but this radionuclide has a very short half-life of eight days. The long-term impact comes from cesium-137 and strontium-90, which have 29- and 30-year half-lives, respectively, and from plutonium-239, which has a half-life of 24,390 years.
If measured by cesium contamination of the soil - and after the summer of 1986 the ground became more dangerous than the air - with a level of 1 curie per square kilometer and above, then 43,000 square kilometers of Ukraine were affected, including 3,200 towns, villages and hamlets. In this region lived 4 million people, including 1.5 million children. Eighteen Ukrainian oblasts were contaminated to some degree.
The fallout of radioactive particles into the Dnipro River affects the water supply of 28 million of Ukraine's 52 million inhabitants.
Moreover a zone of 30-kilometer radius around the Chornobyl nuclear power station was completely evacuated, leaving a dead zone in northern Ukraine and southern Belarus. This area is known as the Polissian Ecological Zone. Its largest town was Prypiat, built in the 1970s for workers of the nuclear plant which housed 45,000 people at the time of the accident.
The areas affected by Chornobyl have several distinctive characteristics:
The Soviet government decided to evacuate 116,000 people in 1986, including 91,000 from the Ukrainian side of the 30-kilometer exclusion zone. Thereafter no information was provided on the radiation situation outside this zone until early 1989 when, thanks partly to glasnost, maps were published in Pravda that indicated a considerably wider area had been contaminated.
Once the republican press followed suit, then further evacuations were ordered. By 1991, the number of Ukrainian evacuees numbered 160,000, but the process was a slow and complex one. Initially the evacuation was based on a radiation limit to the individual of 5 millisieverts (mSv) per year, calculated through the natural background radiation in the air and the amount consumed through food and milk in any given region. It was calculated that any area with over 15 curies per square kilometer in the soil must be evacuated immediately; those with 5-15 curies per square kilometer were designated areas of secondary evacuation; and 1-5 curies required constant surveillance of the area.
By 1991, new tolerance levels were introduced by the Ukrainian government after strong local protests that the 5 mSv criterion posed danger for a population already affected by high radiation fallout. The level was accordingly reduced to 1 mSv per year, hence greatly expanding the area under control. One calculation offered this year is that the zone residents have already accumulated 70 percent of their acceptable lifetime dose of radiation.
Today in Ukraine, according to one study, 12 oblasts with 77 raions remain contaminated, encompassing 3,000 rural villages in north, west and central Ukraine. Evacuations are still taking place, but they are often long delayed - 5,000 settlements in the Poliske region of Kyiv, one of the most heavily contaminated zones of Ukraine, for example, have been awaiting evacuation since 1991.
One problem is that the fallout was uneven. Areas with low levels often contained some hotspots. And, it did not depend on the distance from reactor. Today, though the situation is somewhat improved in the immediate vicinity of the reactor, where topsoil has been removed and various probes taken, it is the same or worse in areas up to 300 miles distant, as radiation levels in the soil have not decreased at all, while levels in the river system, especially of strontium, have risen markedly.
In Ukraine such fallout has damaged 4.5 million hectares of agricultural land. In the underground waters of the Kyiv Oblast in the recent period, probes have revealed that the content of radioactive cesium exceeds the permissible level by more than 100 times.
The penetration of the food chain by radionuclides - especially cesium - is severe. Because of the nature of the soil, radionuclides do not descend more than a centimeter or so each year. They are taken up by livestock and have found their way into milk especially. Based on an acceptable dose load of radiation to the body of 1mSv per year, the radiation content of milk should not exceed 185 becquerels per liter. Of 27,000 tests on milk conducted at the Kyiv-based Center of Radiation Medicine and the Ukrainian Ministry of Health, 11.8 percent contained more than double that amount of radiation. The chief danger today lies with people growing their own food on private plots.
Human toll
The human costs of Chornobyl can be divided into several categories:
Many radiation-induced deaths that occurred thereafter were attributed to other causes. My favorite designation from the Soviet period was "vegeto-vascular dystonia." In one hospital, 53 clean-up workers went on a hunger strike because they felt they were being misdiagnosed this way. The result, surely intended, was the stabilization of the death toll at 31. That figure has no validity.
After the end of May 1986, the campaign was based on military reservists and an estimated 660,000 people took part. The casualties have been high. By last year, according to official Ukrainian statistics, 5,700 had died, many from heart attacks. One report stated that this a normal death rate considering the size of the group. That comment ignores the fact that these were young men in their 20s and early 30s, rather than a sample population. Many died of stress, others from radiation sickness.
Their work involved full body count radiation levels well above the norm for workers in the nuclear industry. Emergency levels of 7.5 mSv were also exceeded many times by those who were forced to rush across the reactor roof in a space suit and throw a handful of graphite into the gaping hole in the fourth reactor. Their time limit lay in seconds.
In addition, liquidators today suffer from a variety of medical and psychological illnesses. Of the 660,000, over 50 percent are currently under medical care of some kind, including for incurable skin diseases, digestive and respiratory problems. Even larger is the figure for those suffering from stress and psychological tension which itself can bring on illness.
It is fair to say that the evacuation has been a disaster from every respect, to wit:
1) It was carried out in piecemeal fashion and in many cases delayed for years so that when it did occur, it was virtually useless unless contamination levels were extremely high. It did not make sense to evacuate people in areas with borderline radiation content in the soil. A move to a polluted industrial city like Kyiv, for example, might raise rather than lower their radiation intake.
b) Moving elderly people out of their native villages caused a great increase in the amount of stress.
Often evacuees were moved to settlements badly constructed, lacking heating and water, adequate sewage facilities, and with little employment for younger evacuees. In cases when people were moved to existing settlements, evacuees were sometimes treated virtually as lepers by the local population who feared contamination simply through contact with them.
d) A recent study in Miensk shows that the 25,000 Chornobyl evacuees have levels of lung cancer four times that of the city average, in addition to a variety of other ailments. In short, it appears that only an immediate evacuation, hours after the disaster, would have served much purpose in less contaminated zones.
e) Since the population was predominately elderly, it would not have made an appreciable difference to their normal lifespan had they consumed some radioactive products. Surely the best plan in the event of the nuclear accident would have been to remove children instantly in addition to providing them with potassium iodide tables. Unfortunately this was not done.
It is among children that the main medical impact of Chornobyl has been revealed. In 1990-1991, however, an IAEA-sponored study was carried out which examined 28 villages of Ukraine and Belarus, and concluded that no discernible health effects from Chornobyl were found, but that others could not be discounted in future.
This study, which ran to 600 pages, did not examine evacuees or liquidators. It was also very much resented by scientists in both Ukraine and Belarus for underestimating the various sources that comprised the radiation dose load of the population, such as hot spots, and for the fact that it was conducted for most part when children were on summer vacation, outside the irradiated zone.
Copyright © The Ukrainian Weekly, May 5, 1996, No. 18, Vol. LXIV
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