Assessement of genotoxicity of Dichlorvos to Mystus vittatus (Bloch) by comet assay

Abstract

In the present study, the genotoxicity of dichlorvos, a widely used organophosphate pesticide, was assessed in the
air-breathing teleost fish Mystus vittatus using comet assay. The specimens were exposed to sublethal concentrations of
pesticide, viz., 0.045 and 0.022 ppm for a period of one week and the blood samples were collected at 24 h intervals for
assessment of DNA damage in terms of Olive tail moment in the erythrocytes. Significant (p<0.01) effects of both concentration
and time of exposure on DNA damage were observed in the exposed fish. The lowest DNA damage was observed on day 1
at sublethal 1 concentration, followed by gradual increase in DNA damage with increase in concentration and duration of
exposure. The study, thus, revealed the potential hazard of the pesticide to fishes and also indicated suitability of the comet
assay to detect DNA damage induced by the pesticide even at lower concentrations.