Nov 30 2006
The public needs to have a better understanding of the safety of nuclear radiation, an Oxford physicist has claimed. While the public is happy to accept the benefits of high doses of radiation in medicine, fears of radiation associated with a civil nuclear power programme are disproportionate.
Wade Allison, Professor of Physics at Oxford University, argues that this public apprehension of anything nuclear, which was fostered during the Cold War, is not justifiable and, with the onset of climate change, nuclear radiation needs to be assessed in more realistic terms when difficult choices between power sources have to be made.
Professor Allison said: ‘Current environmental regulations that attempt to keep variations in radiation exposure to a fraction of the natural level are over-cautions by a factor of about 500 to 1000. This factor is unnecessary and unaffordable. In no other field is such a safety factor applied.’
In his lecture, ‘How dangerous is ionising radiation?’given on 24 November 2006 as part of the mainstream Colloquium series in the Oxford Physics Department, he shows that in fact there is good evidence to demonstrate that life has evolved immunity to the dangers of radiation up to a certain threshold. Below this, any damage is completely repaired.
A value for this threshold may be determined from the health records of the survivors of Hiroshima and Nagasaki, for example. The existence of this threshold, or non-linearity as he describes it, is supported by data on the acute victims of Chernobyl, on laboratory experiments, on radon in homes, on the recovery of patients receiving radiotherapy – indeed, without this non-linearity, current radiotherapy treatment would not be effective.
Professor Allison argues that this threshold behaviour is the norm, describing, for example, how people recover completely from minor cuts and bruises, loss of blood, body temperature excursions and so on, up to a certain threshold. Nuclear radiation, or ionising radiation as he more correctly describes it, occurs naturally in the environment, and mankind has adapted to deal with it by developing repair mechanisms that prevent long-term damage.
Professor Allison said: ‘Members of the public tolerate radiation exposures for their own health which are 1000 times higher per day than those that are currently deemed barely acceptable in the environment per year. A far greater tolerance to radiation in the environment is needed if the health of the planet is to be treated with the same respect and judgment as personal health.’
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