§ Mr. Skeetasked the Secretary of State for the Environment of the oxides of nitrogen present in the atmosphere, what percentage he assesses is derived from (a) industrial sources, (b) vehicle emissions and (c) other sources.
§ Mr. WaldegraveNitrous oxide is generated almost entirely by natural processes and its concentration in the atmosphere is low. The question is taken to refer to nitric oxide and nitrogen dioxide arising from high temperature combustion processes and from nitrogen compounds in fossil fuels. Information on emissions of oxides of nitrogen is given in "The Digest of Environmental Pollution and Water Statistics" published by my Department. The latest figures (for 1981) are: industrial sources 67 per cent., vehicle emissions 26 per cent., other sources 7 per cent.