MUTAGENICITY AND TOXICITY ASSESSMENT OF PULP-MILL EFFLUENT

Data are presented on the mutagenic and toxic properties of both whole and fractionated bleached kraft mill effluent. Mutagenic properties were measured using the Ames test and the SOS Chromotest. Toxic properties were measured using the Microtox and Daphnia magna bioassays. The D. magna bioassays were performed only on four samples, and the information on mutagenicity represent the main emphasis of this study. Various fractionation procedures, including filtration, centrifugation and XAD resin adsorption procedures were employed. Bleached kraft mill effluent (BKME) was found to be mutagenic with the majority of activity associated with polar compounds. Polar material adsorbed by XAD-4 and XAD-8 resins contained a mutagenic potency equivalent to that measured directly in the effluent. Whole effluent samples were non-toxic (Microtox bioassay), but the polar fractions were toxic (Microtox and Daphnia magna bioassays) while particulate associated materials were toxic just to the Microtox bioassay. This paper also comments on the chemical characteristics of mutagenetic materials in these effluent fractions.