§ Mr. Wilsonasked the Secretary of State for the Environment what information he has as to the existence of a synergistic relationship between the two pollutant effects sulphur dioxide and oxides of nitrogen.
§ Mrs. RumboldResearch so far indicates that these two pollutants can be synergistic in their effects in some cases but that in others their combined effects may be equal to, or less than, the effect of each independently. Further research in my Department's programme is aimed at increasing our understanding of these complex relationships.