Toxicity and genotoxicity of surface water before and after various potabilization steps

The Microtox test revealed high toxicity in the treated water samples. The disinfection steps increased the toxicity: the Mutatox test confirmed these results and the Salmonella/microsome test at the highest doses showed toxicity that could conceal mutagenicity. The SOS Chromotest was positive in all treated water samples without metabolic activation. In the test with S. cerevisiae both toxicity and genotoxicity generally increased during the water treatment steps, especially in cells without induction of cytochrome P450.