Contribution of woodsmoke and motor vehicle emissions to ambient aerosol mutagenicity.
A multiple linear regression form of receptor modeling has been used to determine the sources of the mutagenicity (a measure of potential carcinogenicity) of fine-particle ambient aerosol samples collected during the winter in a residential area of Albuquerque, NM. Virtually all the mutagenicity (Salmonella typhimurium TA98 +S9) could be accounted for by woodsmoke and motor vehicle emissions. Woodsmoke was found to be the greater contributor to the average ambient concentrations of both extractable organics and mutagenicity. The mutagenic potency (revertants per microgram) of extractable organics traced to motor vehicles, however, was 3 times greater than that with a woodsmoke origin. The results were confirmed by 14C measurements.