Radiation-How Safeis 'Safe'? Extra, man-made radiation affects people from sources as varied as tooth x-rays to nuclear power plants - but how safe is the dose people are getting? Safety standards are based above all on the study of the extra cancers among survivors of the atom bombing of Hiroshima and Nagasaki. But 40 years on, with new findings, the scientists are drastically revising their ideas of the effects of A-bomb doses.
Radiation is proving more dangerous than believed, and there's growing evidence that British standards, already laxer than countries like the USA, will have to be made more stringent.
With interviews in Hiroshima, Washington and Sellafield, Fred Emery reports.
Producer PETER CERESOLE Editor DAVID DICKINSON