Official bodies like the World Health Organisation and the International Committee on Non-Ionising Radiation Protection will not make promises about mobile phone safety. Scientists don't like to speak in absolutes, and certainties in research are the next best thing to non-existent. What is true today might be disproved tomorrow on the basis of new research. Scientists are much happier to talk about "relative risks", an assessment of the odds that something will go wrong. We all face the possibility of getting smacked with a six-mile wide asteroid from space - leaving nobody behind to worry about mobile phones - but we don't take the risk seriously.

The WHO therefore gives cold comfort to objectors ranged against a new mobile phone mast when it says there is "no convincing evidence" that these masts shorten life span. And when the ICNIRP says there is "no substantive evidence" of adverse health effects it wouldn't make you rush out to buy a phone.