Sir: Bill Bryson is one of my favourite authors, but he cannot get away with his piece on passive smoking (Bryson's America, 17 May). It is always difficult to communicate risks, and the number of deaths caused by different exposures are always difficult to estimate. However, exposure to second- hand smoke is far more hazardous than he states. Amongst common conditions it causes are premature births, cot deaths, respiratory illnesses in children, pneumonia and bronchitis in adults, and angina.
Health educators, politicians and journalists choose emotive markers when trying to convey a message about health hazards. Causing cancer of the lung sounds far better than chest illnesses in children or adults - even though the risk and damage to health is far greater.
Comparing the hazards of passive smoking to eating a pork chop or carrots, drinking orange juice or having a pet budgie is also ludicrous - rather like comparing apples and lemons; both fruits , but completely different. Also, the reports of these hazards are based on perhaps one or two studies, some of dubious quality. By contrast, the inhalation of second-hand smoke has been shown by innumerable studies world-wide to be hazardous.
Emeritus Professor of Public Health Medicine, United Medical and Dental Schools of Guy's and St Thomas' Hospitals
Richmond, SurreyReuse content