POLAR ORGANIC-MATTER IN AIRBORNE PARTICLES - CHEMICAL CHARACTERIZATION AND MUTAGENIC ACTIVITY

Polar organic matter (extracted from inhalable particles collected in Elizabeth, NJ, and from National Institute of Standards and Technology Standard Reference Material SRM 1649) has been characterized by deter mining elemental and ionic composition, chemical classes, and mutageni c activity. The acetone extracts of SRM 1649 and Elizabeth, NJ, sample s were 46 and 40 % carbon, respectively. When compared to the NJ extra ct, the SRM extract was enriched in aldehydes and ketones and deficien t in carboxylic acids. Significant amounts of organic nitrogen were fo und in both extracts. Infrared spectra and class tests suggested the p resence of nitro compounds, organic nitrates or nitrites, amines, and amides. Fluorescence suggested the presence of polycyclic aromatic spe cies. For SRM 1649 the acetone extracts accounted for 36 % (-S9) and 4 0 % (+S9) of the mutagenic activity in the Ames assay with TA98 (speci fic mutagenic activity). The acetone extract of SRM 1649 had about fou r times greater mutagenic activity than that from the NJ particles. Bo th extracts showed substantial decreases in mutagenic activity when te sted with nitroreductase-deficient strains of TA98. A simple resolubil ization of the NJ extract concentrated the most mutagenic components i nto the least polar of the three fractions.