More smog is forecast

Poor air quality is forecast in many of Britain's towns and cities today. London's first smog this winter has lingered over the capital throughout this week, produced by a combination of cold, still weather and fumes from traffic, industry and power stations. Recording stations at several roadside sites measured nitrogen dioxide levels in the Government's "poor" band.

Earlier in the week, in Leeds, Liverpool, Middlesbrough and Southampton, unsafe levels of benzene, created by traffic, were found. Nicholas Schoon