It's not pollution

CONTRARY to common sense, foul air may not be the cause of the rise in the number of asthmatics, at least not in Britain. Though the number of Britons with asthma has risen rapidly in recent years, with the number of deaths doubling over the past two decades, a recent review of studies of the four most critical pollutants -- ozone, sulphur dioxide, particulates and oxides of nitrogen -- has found no strong link between asthma and air pollution (New Scientist, Vol 140, No 1904).

Some experts feel the most likely culprits are smoking during pregnancy, diet and household allergens.