Sir,

I am among many who criticise the WHO for its limited tobacco budgets. But its policies on active and passive smoking are both correct and in line with global public-health opinion.

The 25% increase in the risk of lung cancer from passive smoking, as shown by the"meta-analysis" you cite, is small compared with that for active smokers; but it is real, especially when applied to large numbers of people. This must also be combined with the "irritant" effect of inducing asthma attacks in susceptible people plus an increased risk of emphysema and myocardial infarction. These are avoidable, and many smokers behave in ways that avoid exposing non-smokers as a result. But there is still good reason for legal prohibitions, as they make employers more sensitive to the problems faced by employees such as barmen, who experience a lifelong accumulation of our few "whiffs in a pub", and whose lungs suffer as a result.