COMPARISON OF 3 SHORT-TERM ASSAYS - RESULTS ON 7 CHEMICALS - POTENTIAL CONTRIBUTION TO THE CONTROL OF WATER GENOTOXICITY

Three short-term assays (the SOS chromotest, the Ames fluctuation test and the newt micronucleus test) were used to evaluate the genotoxicit y of seven chemicals (4-nitroquinoline 1-oxide, potassium dichromate, formaldehyde, sodium hypochlorite, benzo[a]pyrene, cyclophosphamide an d 2-naphthylamine). In the SOS chromotest, all seven compounds except sodium hypochlorite and cyclophosphamide were found to induce primary DNA damage in E. coli. With the Ames fluctuation test, all seven chemi cals except sodium hypochlorite showed mutagenic activity on Salmonell a typhimurium TA100, TA102 or TA98. The newt micronucleus assay detect ed a clastogenic effect of all seven compounds except formaldehyde on the peripheral blood erythrocytes of Pleurodeles waltl larvae. For eac h compound, the sensitivity of the tests was compared; (1) the SOS chr omotest is the least sensitive assay in every case, (2) the Ames fluct uation test is the most sensitive assay for studied chemicals with dir ect genotoxic effect and (3) the newt micronucleus assay is the most s ensitive test for tested compounds with indirect genotoxic activity. T he potential contribution of these three tests in the monitoring of wa ter genotoxicity is discussed.