More than 10,000 people have died in the Japanese tsunami and the survivors are cold and hungry. But the media concentrate on nuclear radiation from which no-one has died – and is unlikely to.
Wade Allison is a nuclear and medical physicist at the University of Oxford, the author of Radiation and Reason: the impact of science on a culture of fear. This essay on BBC News World attempts to counter the radiation hysteria:
(…) On the 16th anniversary of Chernobyl, the Swedish radiation authorities, writing in the Stockholm daily Dagens Nyheter, admitted over-reacting by setting the safety level too low and condemning 78% of all reindeer meat unnecessarily, and at great cost.
Bottled water was handed out in Tokyo this week to mothers of young babies
Unfortunately, the Japanese seem to be repeating the mistake. On 23 March they advised that children should not drink tap water in Tokyo, where an activity of 200 Bq per litre had been measured the day before. Let’s put this in perspective. The natural radioactivity in every human body is 50 Bq per litre – 200 Bq per litre is really not going to do much harm.
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.