§ Mr. Skeetasked the Secretary of State for Transport to what extent motor vehicles contribute to the problem of acid rain.
§ Mrs. ChalkerMotor vehicles contribute about 30 per cent. of the total deposition of nitric acids from man-made sources and nitric acid deposition forms about 30 per cent. of total acidity. Emissions from vehicles therefore are thought to be responsible for about 10 per cent. of manmade acid depositions, the remainder coming from industrial sources. However, there is considerable uncertainty about the way in which "acid rain" is produced, and the role of natural sources of acidity.