Bioassay-directed fractionation of mutagenic PAH atmospheric photooxidation products and ambient particulate extracts.

Simulated atmospheric gas-phase reactions of naphthalene, fluorene and phenanthrene have been carried out in an environmental chamber with bioassay-directed chemical analysis of the reaction products. Nitro-PAH were found to be the most significant mutagens formed from the reactions of naphthalene and fluorene. The mutagram (bar graph of mutagenic activity versus HPLC fraction) of the phenanthrene reaction products closely resembled that of an ambient air particulate extract with the most mutagenic activity being in a fraction more polar than that in which the nitro-PAH elute.

Mutagenic activities of selected nitrofluoranthene derivatives in Salmonella typhimurium strains TA98, TA98NR and TA98/1,8-DNP6.

The mutagenic activities of novel nitrofluoranthene derivatives in Salmonella strains TA98, TA98NR and TA98/1,8-DNP6 (with and without S9 addition) are given. These derivatives were produced from the reactions of fluoranthene (FL) and its directly mutagenic 2- and 3-nitro derivatives with covalent dinitrogen pentoxide (N2O5) in CCl4 solution at ambient temperature. The influence of the addition of a nitro group on the observed activity of the resulting di- and tri-nitrofluoranthenes is discussed.