Abstract: | Mutagenic activity in diesel emission particulate extracts was detected by the Salmonella typhimurium/microsome assay. Direct-acting mutagens as well as promutagens requiring metabolic activation were detected. The extracts were fractionated into acidic, basic, and neutral fractions, and the neutral fraction was chromatographed into seven subfractions. Differences in the mutagenic potency of these fractions and subfractions were determined by the Salmonella assay. Fractions containing as yet unidentified compounds, but not polynuclear aromatic hydrocarbons, were found to make a major contribution to mutagenic activity of the extracts. |