MUTAGENIC ACTIVITY IN ORGANIC WASTEWATER CONCENTRATES

Organic wastewater concentrates from six treatment plants were tested for mutagenicity using the Ames mutagen bioassay. Concentrates were prepared by passing 4-8 L of wastewater through two porous copolymer resins (Amberlite XAD-2 and XAD-7) in series. Of four tester strains, TA-98 in the presence of Arochlor-induced rat liver enzymes was the most sensitive indicator of mutagenicity. Mutagenic responses were observed in extracts from most of the plants tested. More activity was found in secondary and post-secondary extracts than in primary extracts. Dose-response curves obtained for selected samples showed a maximum activity of 210 revertants/mg of extract (TA-98 + S-9). Fractionation of positive extracts showed the activity to be primarily in the basic and neutral fractions, while acid fractions were relatively inactive. © 1979, American Chemical Society. All rights reserved.