Mutagenic and genotoxic assessment of atrazine-based herbicide to freshwater fish Channa punctatus (Bloch) using micronucleus test and single cell gel electrophoresis.

The mutagenic and genotoxic effect of 'Rasayanzine', an atrazine herbicide, was carried out in fish Channa punctatus using micronucleus and single cell gel electrophoresis (SCGE) assays. Three sub-lethal concentrations of the test material viz., SL-I (1/5th LC(50)=∼8.48 mgL(-1)), SL-II (1/8th LC(50)=∼5.30 mgL(-1)) and SL-III (1/10th LC(50)=∼4.24 mgL(-1)) were calculated using LC(50) value and the fish specimens were exposed to these concentrations. Erythrocyte and gill cells were sampled on day 0, 1, 3, 5, 7, 14, 21, 28 and 35 of exposure for assessment of micronuclei induction in blood erythrocytes and DNA damage using SCGE assay in both blood erythrocytes and gill cells. Significant effects (p<0.01) for both concentration and time of exposure were observed in treated fish. Micronuclei induction in erythrocytes was highest (8.4 mgL(-1)) on day 7 of exposure. The highest level of DNA damage in the SCGE was observed in both tissues on day 5 at all concentrations followed by gradual non-linear decline. This study further confirmed that the micronucleus and SCGE assays are useful in determining potential genotoxicity of water pollutants and might be appropriate as part of monitoring program.