§ Mr. Adleyasked the Secretary of State for the Environment what proportion of air pollution caused by energy-conversion processes is attributable to the internal 372W combustion engine and to aircraft, respectively.
§ Mr. Peter WalkerThe Warren Spring Laboratory's study of air pollution at and around Heathrow Airport in 1970 showed that pollution levels there were lower than is normal in an urban residential area; the contribution of aircraft exhausts to national pollution is therefore negligible. Of total carbon monoxide emissions in Great Britain about 40 per cent. comes from motor vehicles. Other pollutants emitted by motor vehicles include hydrocarbons, oxides of nitrogen and lead. In these cases, exact emission figures are not available.