Assessment and characterization of genotoxic water contaminants with modern genotoxicological methods

The necessity of genotoxicological studies in water requires modern and pra cticable concepts for a prospective environmental protection. Up to now, ge notoxicological studies prefer only the observation and detection of basic genotoxic effects in enriched surface water samples and the fruitless searc h for the involved water contaminants. In this publication, a new test stra tegy for the detection and the assessment of genotoxicity in water will be introduced, This strategy allows the detection and the verification of posi tive results and is therefore able to assess the evidence of these results for the water quality more accurate. The aim of this strategy is the detect ion of basic genotoxic effects (primary DNA damages), the clarification of the biological mechanisms, and the search for the reasons with modern analy tical methods. The involved water contaminants and their mode of action wil l then be better understood. A test strategy in three steps will be propose d. In the first step genotoxicological indicator tests such as comet assay, alkaline filter elution, or the SOS-umu-test are used to get information a bout the basic status of the tested water samples. In the second step, the positive results of the primary DNA damages will be verified with mutation tests such as the micronucleus assay. The involved biological mechanisms wi ll be biochemically characterized, and the biological active substances wil l be preclassified. Finally, in the third step the observed mechanisms will be confirmed with modern chemical methods such as HPLC MS-MS. These modern techniques are also able to detect and quantify the genotoxic compounds pr eclassified in step two.