Genotoxic activity of pulp mill effluent in Salmonella and Saccharomyces cerevisiae assays

An XAD-2 resin concentrate of chlorination-stage pulp mill effluent was found to induce mutations in Salmonella typhimurium strains TA1535, TA100 and TA98 but not in strains TA1537 or TA1538. The presence of either S9 mix, S9 mix without cofactors, or heat-inactivated S9 mix, reduced the mutagenic effects. Dose-related increases in gene conversion, mitotic recombination and aberrant colony formation in Saccharomyces cerevisiae strain D7 also were found.