文摘
Few reports have characterized mutagenic compounds inrespirable airborne particles (<2.5 micrometers indiameter; PM2.5) collected at different sites on a regionalscale (hundreds of km). Previously, we reported differencesin the human (h1A1v2) cell mutagenicity of whole andfractionated organic extracts of PM2.5 samples collectedin Boston, MA, Rochester, NY, and Quabbin Reservoir, a ruralsite in western MA. Herein we describe the analysis ofmutagens and other organic compounds in these samples.Gas chromatography-mass spectrometry (GC-MS) wasused to quantify ~150 organic compounds, including 31 knownhuman cell mutagens. Molecular weight (MW) 226-302amu PAHs were the most important mutagens identified:cyclopenta[cd]pyrene accounted for 1-2% of themeasured mutagenicity of the samples, MW 252 PAHsaccounted for 4-6%, MW 276-278 PAHs accounted for2-5%, and MW 302 PAHs accounted for 2-3%. 6H-benzo[cd]pyren-6-one, a PAH ketone, accounted for 3-5% ofthe mutagenicity. The same compounds accounted for similarportions of the total attributed mutagenicity in eachsample. Mutagen levels were similar in the Boston andRochester samples, and both were significantly higher thanthe Quabbin sample. This may explain why the mutagenicitiesof the Boston and Rochester samples were higher thanthe Quabbin sample. The levels of mutagens found in semipolarfractions, however, could not explain why the mutagenicityof semipolar fractions was 2-fold higher in the Rochestersample than in the Boston sample. Known mutagensaccounted for only 16-26% of the total mutagenicity ofthe unfractionated extracts, and only ~20% of the mutagenicityof the nonpolar and semipolar fractions. The remainingmutagenicity is likely attributable to other, as-yet unknown,semipolar and polar mutagens, or to interactions amongchemical constituents of the samples. These findings areconsistent with similar studies performed on airborne particlesfrom Los Angeles and Washington, DC, thus indicatingthat PAHs, PAH-ketones, and as-yet unidentified polar organiccompounds are widely distributed airborne human cellmutagens.