Under the Microscope/Prof William Reville: The worst nuclear fission power accident in history occurred in 1986 at Chernobyl and it seemed to sound the death-knell of the nuclear industry.
However, nuclear energy has tip-toed back onto centre stage because our conventional generation of power by burning fossil fuel is dangerously warming the world by releasing huge amounts of carbon dioxide. Unless we stop these releases right away we will precipitate marked global climate change, probably with disastrous consequences for mankind. A widespread changeover to nuclear fission power may be our only hope of avoiding disaster.
We may have gone too far already. The British scientist James Lovelock formulated the powerful Gaia model of the earth in 1972. Gaia theory proposes that living organisms on earth, of which mankind is but a small component, together with the earth's surface and atmosphere, unconsciously regulates the earth's temperature for the benefit of life.
In his latest book, The Revenge of Gaia (Allen Lane 2006), Lovelock argues powerfully that we are at imminent risk of kicking the Gaia mechanism into a new equilibrium that will be entirely hostile to mankind. Sweltering heat and global flooding of coastal areas would mutilate civilisation, dumping us back to pre-modern conditions. He recommends that our only hope of helping ourselves is to immediately stop pumping warming gases into the atmosphere.
We can stop releasing carbon dioxide by using renewable energy such as sun, wave and wind, or by using nuclear energy. However, the expert consensus is that renewable energy can provide only a fraction of our energy needs over the medium term. Lovelock concludes we must massively switch over to fission nuclear energy in order to tide us over the next 50 years until safe, clean nuclear fusion energy is available, supplemented by the best we can squeeze out of sun, wind and wave.
I have always opposed nuclear fission power because of the possibility of a disastrous accident and also the highly radioactive waste that it generates. But these problems are not as intractable as they once seemed. Chernobyl excepted, the nuclear industry has a good safety record. The Chernobyl reactor had design flaws and the exercise that caused the explosion was improper and illegal. Western nuclear power stations have been very safe and, since Chernobyl, improvements in design have made reactors safer still.
High-level nuclear waste is undoubtedly problematic. However, it can be stored in deep geological repositories and research promises to find ways of transforming this waste into a form that needs to be stored for only 1,000 years, as opposed to the 100,000 years presently necessary. In summary, if the only way to avoid disastrous climate change is to switch over to nuclear fission power for a while, then we must take the nuclear option and we can easily live with it.
The Chernobyl Forum recently reported (April 2006) on the health, environmental and economic effects of the accident, generating much public commentary. The report details the findings of more than 100 expert scientists, the collaboration of eight UN agencies (including the World Health Organisation) and the governments of Russia, Belarus and Ukraine.
The Forum Report estimates that of the 6.8 million people most exposed to radiation, up to 9,000 people may die sooner than they otherwise would, due to radioactive releases from the accident. It is also estimated that, of the 570 million people in Europe exposed at the time of the accident, up to 16,000 people will ultimately die over the next 70 years as a result of Chernobyl.
However, as of mid-2005, fewer than 60 deaths can be directly attributed to Chernobyl radiation, mostly highly-exposed rescue workers who died within months of the accident. About 4,000 cases of childhood and adolescent thyroid cancer are attributed to radiation exposure. Ninety nine per cent of thyroid cancers were treated successfully, but at least nine children died. Otherwise the experts found little evidence of increased cancer incidence amongst affected residents.
The report attributes a modest increase in reported newborn congenital deformities to better reporting of these deformities after the accident and not to radiation. The reported increases are seen both in radiation-contaminated areas and in areas that received no fallout. The congenitally deformed Chernobyl children taken abroad by the Chernobyl charities are not radiation victims, but representatives of the 1.5 per cent of births everywhere that display congenital deformities.
The report concludes that the largest public health problem resulting from the accident is "the mental health impact". Most people in contaminated areas received low radiation doses, comparable to natural background radiation levels, which could have little or no effect on health. Nevertheless, they continue to suffer grave anxiety which has prevented them from restarting their lives. A "paralysing fatalism" has led to drug and alcohol abuse, unprotected sex and unemployment. The report recommends that the first priority should be to encourage these people to normalise their lives by educating them about the minimal risks they face.
Prior to the Chernobyl Forum Report, many assumed that hundreds of thousands of people died as a result of the accident. Some amateur groups are now contradicting the report, citing anecdotal evidence and reports commissioned by the Greens. On the other hand, the Chernobyl Forum Report represents many years intensive study by mainline science and it has the imprimatur of the WHO. Any notion that such a huge undertaking was put together to "whitewash" the nuclear industry is incredible, not to mention insulting to the many decent professionals involved in the study.
William Reville is associate professor of biochemistry and public awareness of science officer at UCC - http://understandingscience.ucc.ie