Analysis of Polycyclic Aromatic Hydrocarbons on Vapor-Grown Carbon Fibers

Evidence for a new class of mutagens in diesel particulate extracts

“…1-Nitropyrene was quantified in fraction 4 from two independent HPLC fractionations of the same extract. The concentrations of 1-nitropyrene in these two HPLC fractionations were 38 ± 7 and 49 ± 10 ng//ug of fraction 4. Quantification of the amount of 3-nitrofluoranthene and 8-nitrofluoranthene in fraction 4 was difficult because these two compounds coeluted from the GC column and they were detected only from a extract concentrated to approximately 7io of the original volume.…”

“…In strain TA102, about 12-18% of the mutagenicity of fraction 4 could be accounted for by these nitroarenes. Since fraction 4 represents 3% (Table I) of the total mutagenicity of the extract, these three nitroarenes account for ~0.5% [(0.18) (0.03) = 0.0054] of the total TA102 mutagenicity applied to the column.…”

“…Quantification of Nitroarenes. 1-Nitropyrene in the diesel particle extract eluted in fraction 4 and was quantified using a GC-MS (Hewlett-Packard Model 5970 GC-MS system) with selected-ion monitoring at m/e 201, 217, and 247. Samples were injected via the splitless injection method onto a 30-m DB-5 capillary GC column with the oven held at 40 °C for 4 min, followed by ramping (4 °C) the temperature to 300 °C and holding at this temperature for 5 min.…”

“…Organic solvent extracts of these particles contain most of the organic compounds originally bound to the particles, and these extracts are mutagenic in the Ames assay using strains TA98 and TA100. The compounds responsible for the direct-acting mutagenicity of these extracts have been positively identified for 30-50% of the total mutagenicity using strain TA98 (1)(2)(3)(4)(5). We define direct-acting mutagenicity to mean those compounds that are mutagenic without the addition of metabolizing enzymes.…”

“…We define direct-acting mutagenicity to mean those compounds that are mutagenic without the addition of metabolizing enzymes. Directacting mutagens identified in diesel particle extracts include nitropyrenes, nitrofluoranthenes, dinitropyrenes, hydroxynitropyrenes, and acetoxynitropyrenes (1,(3)(4)(5). In addition, there is evidence, from the reduction of diesel particle extracts by sodium borohydride, suggesting that a majority of the direct-acting mutagenicity is due to compounds that are more easily reduced than 1-nitropyrene (e.g., dinitroarenes) (2).…”