World’s worst nuclear accident

Twenty years since Chernobyl

This April marks the twentieth anniversary of the Chernobyl catastrophe, the world’s worst nuclear accident. The explosion at the power plant, situated about 100 miles north of Kiev in the Ukraine, then part of the Soviet Union, sent a cloud of radioactive gas around the world. The cloud contained twenty times the amount of radiation released at Hiroshima.

Estimates made at the time in the New Scientist magazine, that 100,000 would eventually die as a direct and indirect result of the radiation release, may have been too high. But if the wind had been blowing in the opposite direction on the day, towards the densely populated city of Kiev instead of over relatively sparsely inhabited areas, the outcome would have been worse than even the New Scientist estimate.

The reactor at Chernobyl was a boiling water, graphite moderated type called a RBMK, many of which are still in operation in the states of the former Soviet Union (the final reactor at the Chernobyl power station was only shut down 15 years after the incident). It is inherently unsafe in a nuclear reactor to have high temperature graphite close to steam under pressure, but this is what happens in the RBMK.

In this type of reactor, the uranium fuel rods are surrounded by graphite, which absorbs some of the heat of the nuclear reaction, a process essential to control its speed. Water is pumped past the fuel rods and graphite to carry away more of the heat, and the steam produced is used to drive turbines to produce electricity. In addition, the graphite has to be surrounded by helium and nitrogen gas to stop it burning in the surrounding air. If the hot graphite and the uranium rods come into contact with the steam an explosion is possible, producing a cloud of radio-active steam. This is exactly what happened in April 1986. The scale of the accident was made worse because there was no containment structure around the reactor that could have prevented the steam from escaping into the atmosphere.

The immediate reason for the explosion lay in the effects of a sudden power surge causing a rupture in the pipes holding the cooling water, thus bringing water into contact with the graphite. The power surge occurred in the first place because of a reckless experiment that was being conducted by technicians on an under-power reactor. Their aim was to speed up the time it took to repair faults.

The technicians were scapegoated at the time, but the reason they were conducting the experiment in the first place was linked to the then power crisis in the Soviet Union. Nuclear stations are usually operated to provide ‘base load’ electricity, that is they are operated 24 hours a day because it is difficult and time consuming to stop and start a reactor. If there are frequent faults, which means that the reactor has to be switched off, its efficiency is drastically reduced. As a result, the technicians were under pressure to come up with a quick and easy answer to the problems caused by the frequent faults in the power plant.

The real costs of nuclear

Western observers at the time, as they will probably do again now, highlighted features specifically linked to the Soviet system that contributed to the disaster, such as the reckless behaviour of the staff, driven by an impatient, bullying bureaucracy, themselves pressurised by the deep problems in the economy, combined with the poor design and unreliability of the power plant. However, the underlying cause, which was a combination of human error and mechanical failure, was the same as occurred at the major nuclear accident in the USA at Three Mile Island in 1979.

The nuclear plant there was based on a PWR (Pressurised Water Reactor), the same type that is used at the Sizewell power station in Britain. During the crisis at Three Mile Island the radio-active material at the core of the reactor came within 700F degrees of its melting point of 5,000F. If such a melt down had occurred there would have been a major disaster, possibly worse than at Chernobyl, since the melting uranium could have penetrated deep into the earth, contaminating ground water over a wide area.

Advocates of nuclear power will point to the low theoretical risk of an accident happening, but this must be set against the potentially catastrophic scale of any incident when it does occur. There are also risks of nuclear power generation not directly connected to the safety of the operation of the plant. These are primarily linked to the problems of safely reprocessing and storing the toxic waste that is produced as a by-product of nuclear power. Evidence appeared decades ago that the incidence of childhood leukaemia close to the reprocessing facility at Sellafield in Cumbria was significantly raised. In the town of Seascale, just over a mile from the plant, children under the age of ten had an incidence of leukaemia ten times the national average, although a government-sponsored report at the time said this was not significant. In the USA, at a naval ship yard in Maine, the overall death rate of workers involved in nuclear related tasks was twice the national average and the occurrence of leukaemia 45% higher then expected. These workers were exposed to very low levels of radiation, well within ‘safety limits’, indicating that there is probably no safe dose of radiation in these circumstances.

Potentially even more serious than the health problems linked to low level radiation leakage associated with reprocessing is the issue of storing toxic nuclear waste. A direct consequence of producing electricity with nuclear reactors is the accumulation of radioactive waste, uranium and plutonium. Apart from electricity generation, there is a significant amount of plutonium produced for military purposes which also has to be stored. To give an idea of the scale of the problem, the amount of toxic nuclear waste stored in the USA in 1991 was 4,900 cubic metres, with a radioactivity of 24,000 MCi (a curie is a quantity of radioactivity, MCi is one million curies). To put this in perspective, a typical radioactive source used in a classroom for a science experiment has an activity of one millionth of a curie. An average sized 1,000 megawatt (MW – one million watts), nuclear power station reactor has a total radioactivity of 70 MCi in its spent fuel one year after discharge. After 100,000 years this figure will fall naturally to 2,000 MCi, still two billion times more radioactive than a typical source used in a classroom. (There is far more waste to store now of course, compared to 1991, and the amount is increasing all the time.)

The implication of this data is that a safe storage method must be found that can be guaranteed to be secure for more than 100,000 years, a task that poses huge uncertainties and problems because it is difficult to predict what natural conditions will be after that time. If the waste is buried, the onset of earthquakes in previously unaffected areas is possible, for example. If the radioactive spent fuel is put at the bottom of the ocean the integrity of the materials used as a storage medium must be uncertain after such a long time, possibly leading to seepage. Also undersea volcanic activity could start, producing the same result.

Technical difficulties, and the understandable opposition from local communities where it has been proposed to dump the waste, have meant that there will probably be at least another ten years’ delay before any supposedly safe site is ready in the USA, and another 20 in Europe. In the meantime, much of the West’s toxic waste is being dumped on poor countries.

A new pro-nuclear drive

Since the twentieth anniversary of Chernobyl coincides with the beginning of a new pro-nuclear drive by the capitalist class in Britain and internationally, commemorating the victims of the disaster in the Ukraine will be an embarrassment for Bush and Blair, one which they will try to downplay as much as possible. This could take the form of distorting or trying to bend the record about Chernobyl’s true impact, a campaign that has already begun in sections of the media.

The political need for a new pro-nuclear position, that the Chernobyl commemoration threatens to stand in the way of, is a direct result of the looming threat of global warming, a reality that most capitalists accept now as a scientific fact and have belatedly started to respond to. In Britain Blair has announced a ‘national conversation’ about expanding nuclear power, which translated from Blairspeak means he has already made the decision to go ahead with it and the conversation he wants is about how best to sell the idea. Other world (mis)leaders are moving in the same direction because they realise that the Kyoto treaty, which is a market-based approach to tackling climate change, has proved so far to be totally ineffective. Despite noisy supportive rhetoric for Kyoto (except from Bush), the imminent turn to nuclear is a recognition of its bankruptcy.

Developing nuclear power has become the preferred option for international big business for several reasons. Firstly, by a lucky co-incidence, it does not produce any greenhouse gases, in contrast to energy generated from fossil fuels such as oil, and so meets the main criteria, if of course the huge safety issues are ignored. Second, nuclear power is relatively cheap to generate, since it utilises a well-established technology, and long-term issues such as paying for safely storing nuclear waste for the indefinite future, meeting the costs of any future nuclear accident, and decommissioning radioactive power plants, will be ignored or glossed over. Having said this, though, nuclear will still be far more expensive than pumping oil out of the desert, so why are the bosses who stand to lose most if global warming is tackled, particularly in the USA which is the biggest culprit, willing to contemplate a hit on their profits by going down this route?

One reason is that Hurricane Katrina brought home, even to the most bone-headed of the American capitalists (except Bush of course, who represents the big oil firms) that there are real long-term costs linked to the effects of global warming that will have to be factored into the equation. Also, although individual firms will never voluntarily opt for intrinsically more expensive nuclear energy sources, governments, even in the US, could go down this road if the extra short-term costs were relatively small and were not perceived to hit international competitiveness excessively. Another factor that could sweeten the pill for the USA is that the American Westinghouse firm, with its PWR-type nuclear power plant, is likely to dominate an expanded world market.

The move to nuclear power could, however, be reversed when there is a significant economic downturn that puts profits under pressure, leading to the need to cut costs even more ruthlessly than in the recent past. In these circumstances, putative nuclear plans could be ditched in favour of a return to more profitable fossil-fuel based energy generation. What is not likely to happen is that Blair, Bush, or any of their successors, will opt for a safe, sustainable option, based on renewable energy sources such as wind, wave or solar power, because the cost of doing this will very significantly hit the profits of the multi-nationals that they represent. For the moment at least most world leaders are swinging behind nuclear power and will not welcome any true assessment of the Chernobyl disaster.

Re-writing the record

When the Chernobyl reactor went into meltdown no news was released by the Soviet government of the radioactive cloud escaping into the atmosphere.

Days later the world became alerted when Swedish nuclear power workers were found to be contaminated with radioactivity – before going into work. Ever since, governments and the nuclear power industry have tried to play down the effects of Chernobyl on health.

Two early estimates of the likely number of deaths were ‘5000 to 10,000 fatal cancers over the next 70 years’ (International Commission on Radiological Protection) and ‘less than 25,000 worldwide’ (International Atomic Energy Agency – IAEA).

Twenty years later a renewed attempt is being made to cover up Chernobyl’s effects on health. Last September a report was issued by the Chernobyl Forum, set up by a number of agencies including the IAEA, the World Health Organization, a number of United Nation (UN) bodies and the governments of Belarus, the Russian Federation and the Ukraine.

Accompanying the report was a press release, entitled ‘Chernobyl: the true scale of the accident’, and subtitled, ‘20 years later a UN report provides definitive answers and ways to repair lives’. This got wide publicity. “A total of up to four thousand people could eventually die of radiation exposure from the Chernobyl nuclear power plant accident”, it said. “As of mid-2005, however, fewer than 50 deaths have been directly attributed to radiation from the disaster, almost all being highly exposed rescue workers, many of whom died within months of the accident”.

Even the Forum’s estimate has been challenged as too high. The Nuclear Industry Association has put the number of deaths at 41, with the possibility of a few more in the future. Dr Zbigniew Jaworowski, a former chairman of the UN Scientific Committee on the Effects of Atomic Radiation, says the only firm number of deaths are 28 who died on site. A higher cancer rate is because increased screening is finding cases that would otherwise have remained undetected, he argues. (Lexington Institute) So was Chernobyl less dangerous than first thought?

In fact the Chernobyl Forum report does not support the misleading headlines of its press release. The ‘fewer than 50 deaths’ directly attributed to radiation relates only to those who died from acute radiation sickness. It does not include those who are dying from cancers, or who will develop cancers in the future, as a result of exposure to radiation. The report itself estimates 8,930 cancer deaths expected in Russia, Ukraine and Belarus among 200,000 ‘liquidators’ (soldiers and workers who cleared the site), 135,000 evacuees and 7.1 million residents of the most contaminated areas.

And it has serious deficiencies. It excludes up to 600,000 liquidators. Most were men aged 20-40 in the armed forces, miners, fire-fighters and other workers. They would normally have been fitter and had a much lower death rate than the general population – the so-called ‘healthy worker effect’. But the report compares the death rates of liquidators with the Russian population as a whole, rather than men of the same age who had not been exposed.

An important study published eleven months before the report was not referred to. This compared the rate of new cancer cases in Belarus liquidators with adults of the same age in the least contaminated part of that country. It showed a 20% increase in the total number of liquidators’ cancers.

This study also compared cancer rates with those of 1976-85. There was an average 40% increase in cancer incidence, with a 56% increase in the most contaminated region. Most cancers have a latent period (between exposure and time of disease) of many years. Increased cancer rates are still being detected in Hiroshima survivors, sixty years after exposure. Such an increase in Belarus after only 15 years is alarming, suggesting many more in years to come.

The report also excludes deaths in other countries. Although exposure was low, a very large number of people were affected. Studies have shown a 30% increase in leukaemia in the US for babies born in 1987 and 1988, a 260% increase in Greece and 387% increase in Scotland and Wales (twelve cases with only three expected). Using conservative radiation risk estimates, the US Department of Energy predicted 17,400 excess cancer deaths over a 50 year period, 63% of these occurring outside the former USSR, mostly elsewhere in Europe.

The Forum’s report excludes non-cancer deaths. Two per cent of all deaths of Russian liquidators between 1986-98 were estimated to have been due to heart and circulation disease caused by radiation. This is almost as much as cancer deaths due to radiation (2.6%).

The President of the Australian Medical Association for the Prevention of War, Professor Tilman Ruff, has added to the report’s estimate of 8,930 excess cancer deaths in the three most affected countries: 4,400-6,600 cancer deaths in the liquidators for whom risk estimates have not yet been made; 5,077-6,769 estimated excess heart-related deaths in all the liquidators; 10,920 excess cancer deaths outside the three worst affected countries (based on the US Department of Energy figures); an additional 20% of cancer deaths (4,850-5,290) in future generations. This yields an estimate of 34,200-38,500 deaths.

It does not include deaths from suicide, alcohol and drug abuse, genetic effects or other causes, all of which are significantly increased in the most severely contaminated zones and among evacuees. And it does not include the suffering of those who have not got a fatal illness, but who live in fear that they will die prematurely because of their exposure to radiation.

The biggest health problems so far have not been fatal illnesses but mental health problems among evacuees and liquidators. Chernobyl pulled communities apart, uprooted families and left them without work or their homes. A similar disaster must never be allowed to happen again.

All commentators agree that there have been major mental health problems in the communities who were uprooted from their homes and who lost jobs. But not all agree that this was the responsibility of the Stalinist Soviet government who failed to protect them and then provide for them, followed by the governments that ruled as the wealth (and health) of the former USSR plummeted during the restoration of capitalism. The US-born Ukrainian, Mary Mycio, for example, has a Thatcherite explanation of their problems.

“The exaggerated awareness of ill health and sense of dependence has created… the ‘Chernobyl accident victim syndrome’.

“Given more than 40 types of Chernobyl benefits, some residents of contaminated areas in Belarus can be eligible for quite large sums of money. For example, working single mothers raising children under the age of three in contaminated districts get about $30 a month – which is around one-third the average Belarusian wage and which may help explain the rise in birth rates in contaminated regions.

“It may also have something to do with the rise in infant mortality in contaminated regions in the late 1990s – contrary to the trend of lower infant mortality in the rest of the country. More study is needed to figure out if this is due to radiation, poor health, and poor social services in contaminated regions or to the outward migration of educated young people. But the system of Chernobyl benefits gives single women who may lack the education, health, skills, or desire for parenting an incentive to have children and raise them in contaminated lands”.

Wormwood Forest: A Natural History of Chernobyl (2005) Joseph Henry Press

From The Socialist, paper of the Socialist Party, cwi in England and Wales

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