We should stop running away from radiation

In the Cold War era most people were led to believe that nuclear radiation presents a quite exceptional danger understood only by "eggheads" working in secret military establishments.

To cope with the friendly fire of such nuclear propaganda on the home front, ever tighter radiation regulations were enacted in order to keep all contact with radiation As Low As Reasonably Achievable (ALARA), as the principle became known.

This attempt at reassurance is the basis of international radiation safety regulations today, which suggest an upper limit for the general public of 1 mSv per year above natural levels.

This very low figure is not a danger level, rather it's a small addition to the levels found in nature - a British person is exposed to 2.7 mSv per year, on average. My book Radiation and Reason argues that a responsible danger level based on current science would be 100 mSv per month, with a lifelong limit of 5,000 mSv, not 1 mSv per year.

New attitude

People worry about radiation because they cannot feel it. However, nature has a solution - in recent years it has been found that living cells replace and mend themselves in various ways to recover from a dose of radiation.

These clever mechanisms kick in within hours and rarely fail, except when they are overloaded - as at Chernobyl, where most of the emergency workers who received a dose greater than 4,000 mSv over a few hours died within weeks.

However, patients receiving a course of radiotherapy usually get a dose of more than 20,000 mSv to vital healthy tissue close to the treated tumour. This tissue survives only because the treatment is spread over many days giving healthy cells time for repair or replacement.

In this way, many patients get to enjoy further rewarding years of life, even after many vital organs have received the equivalent of more than 20,000 years' dose at the above internationally recommended annual limit - which makes this limit unreasonable.

A sea-change is needed in our attitude to radiation, starting with education and public information.

Then fresh safety standards should be drawn up, based not on how radiation can be excluded from our lives, but on how much we can receive without harm - mindful of the other dangers that beset us, such as climate change and loss of electric power. Perhaps a new acronym is needed to guide radiation safety - how about As High As Relatively Safe (AHARS)?

Modern reactors are better designed than those at Fukushima - tomorrow's may be better still, but we should not wait. Radioactive waste is nasty but the quantity is small, especially if re-processed. Anyway, it is not the intractable problem that many suppose.

Some might ask whether I would accept it if it were buried 100 metres under my own house? My answer would be: "Yes, why not?" More generally, we should stop running away from radiation.