The toxic potential of an industrial effluent determined with the Saccharomyces cerevisiae-based assay

Increasing levels of environmental pollution and the continuous monitoring of water quality both request specific and sensitive methods for the detection of detrimental water contents. On a regulatory basis genotoxicity is assessed by the standard umu-test (ISO 13829) that responds to DNA damage induced by chemicals. The focus of this study was the examination of the toxic potential of samples taken from the wastewater treatment plant of a refinery factory to explore the applicability of the Saccharomyces cerevisiae (bakers yeast) test for the detection of bio-available genotoxic activity in complex matrices. The toxic potential of samples without pre-treatment and following centrifugation was determined with the eukaryotic Saccharomyces cerevisiae bioassay based on the transcriptional activation of the green fluorescent protein (gfp) fused to the DNA damage inducible RAD54 promoter and general growth inhibition. Primary effluent samples were taken as qualified sterile spot samples from the final effluent of the purification plant. The Saccharomyces cerevisiae assay yielded geno- and cytotoxic responses in all complex untreated and centrifuged samples with high reproducibility. The obtained results suggest that the yeast assay is suited as a screening tool to monitor genotoxic potential of wastewater.