Sir, - Dick Ahlstrom's article (May 25th) refers to "grey areas" of scientific knowledge with respect to risk, in this case, of brain cancer.
Where grey areas exist in respect of public safety, the central issue must be: who bears the burden of proof? Is it for the consumers and their representatives / advocates to prove that mobile phones are unduly hazardous, or is it for the mobile phone industry to demonstrate that these instruments are acceptably free of risk. In both cases the public would have to define, in measurable terms, what "unduly" and "acceptable" meant. The current acceptability of car-driving risk is a false analogy; if the modern automobile were to be created de novo, its use would surely be prohibited today on grounds of public safety.
Where grey areas exist in respect of the safety of new technology, as also with genetically modified crops, the burden and cost of proof must surely lie with those who expect to profit from the introduction of inessential products. - Yours, etc., John Kevany,
Killiney, Co Dublin.