Evaluation of the Relationship between PAH Content and Mutagenic Activity of Fumes from Roofing and Paving Asphalts and Coal Tar Pitch

Evalution of the Relationship between PAH Content MutagenicAcitivity of Fumes from Roofing and Paving Asphalts and CoalTar Pitch. MACHADO, M. L., BEATTY, P. W., FETZER, J. C., GLICKMAN,A. H., AND McGINNIS, E. L. (1993). Fundam. Appl. Toxicol. 21,492–499. Fume condensates from asphalt and coal tar pitch were evaluatedto determine if polycyclic aromatic hydrocarbon (PAH) composition,crude oil source, or temperature at which the fume was generatedcorrelated with mutagenic activity. The fume condensates weretested for mutagenic activity using a modified Ames Test. Benzo[a]pyrene(BP) and other PAHs were detected in all samples. The concentrationof BP in coal tar pitch was 18, 100 ppm while the concentrationin asphalt was less than 6 ppm. Coal tar fumes contained betweentwo and three orders of magnitude more BP, as well as otherPAH species, than asphalt fumes. Coal tar fume condensates werealso approximately 100 times more mutagenic than those of asphalt.Generation temperature, crude oil source, and/or process conditionsaffected the PAH concentrations but not the mutagenicity inroofing asphalt fume condensates. With paving asphalt fumes,PAH content and mutagenicity varied with crude oil source butnot with processing conditions; due to limited data, it wasnot possible to determine the effect of generation temperature.Coal tar pitch fumes generated at 316°C contained significantlyhigher concentrations of PAHs than those generated at 232°Cand the mutagenic activity generally paralleled the PAH content.A subset of the paving asphalts demonstrated good correlationbetween mutagenicity and three- to seven-ring PAH content. Theseresults indicate that asphalt fumes are far less mutagenic thancoal tar fumes. Asphalt fumes differ in their ability to inducemutagenic activity, and, most likely, in their potential carcinogenicity.