MUTAGENICITY AND TOXICITY OF WATER EXTRACTS FROM THE SORA RIVER AREA

The present study was conducted on the waters of the Sora river and ef fluents entering to the river. The samples were extracted with XAD-2 r esin at different pH and tested for mutagenicity with the modified Ame s test using strains S. typhimurium TA98 and TA100. The majority of th e mutagenic activity of the samples was found in the neutral pH fracti on of the extracts. Strain TA98 in the presence of metabolic activatio n was the most sensitive condition of mutagenicity. Of the eleven samp le extracts, six were positive; neutral fractions of the effluent from wastewater treatment plant, the water leaching from the municipal dum p, the water from the lake lying beneath the dump and the untreated ef fluent, and acid fractions of two samples taken directly from the rive r. The water leaching from the municipal dump was also mutagenic and t oxic without previous extraction. Mutagenic responses before and after extraction of this sample indicate that components responsible for mu tagenicity were partly extracted in the neutral fraction. The toxicity of water samples and extracts was tested with Microtox assay, and aci d fractions of the extracts were more toxic than the neutral fractions . Comparing the toxicity to the mutagenicity data indicates that compo nents responsible for toxic and mutagenic response were at least partl y separated between acid and neutral fraction respectively.