Bioassay-directed fractionation of PAH of molecular mass 302 in coal tar-contaminated sediment

Bioassay-directed fractionation was used to characterise genotoxic polycycl ic aromatic hydrocarbons (PAH) of molecular mass 302 amu in organic solvent extracts of coal tar-contaminated sediment from Sydney Harbour, Nova Scoti a. A normal phase HPLC technique was employed to separate PAM-rich solvent extracts into fractions containing PAM of single molecular mass classes. Th e 302 amu molecular mass fraction was isolated and further separated using reversed phase HPLC; subfractions were collected every 30 s and subjected t o bioassay analyses with Salmonella typhimurium strain YG1025 with the addi tion of oxidative metabolism (4% S9). Compounds eluting in the most active subfractions included naphtho[2,1-a]pyrene and naphtho[2,3-a]pyrene. The re sults of this study underscore the significant contribution that molecular mass 302 PAH make to the biological activity of complex environmental mixtu res. (C) 1999 Elsevier Science B.V. All rights reserved.