From Bernard Stay, St Albans, Hertfordshire, UK
Much recent coverage of our problematic air quality fails to mention that the World ÎçÒ¹¸£Àû1000¼¯ºÏ Organization recently that evidence shows that diesel exhaust causes cancer (for example 6 May, p 35). Its carcinogenicity is attributable largely to particulates depositing free radicals in the lungs. The transport and other special lobbies are much happier to talk about nitrogen oxides – which are probably less dangerous and certainly more easily reduced.
