Genotoxic potential of pesticides in the peripheral blood erythrocytes of fish (Oreochromis mossambicus)

The marine environment as a greater part of the world ecosystem is vital source of nourishment and its safety is linked to our health. the micronucleus (mn) assay has been used to evaluate genotoxicity of many compounds in polluted marine ecosystems. the aim of this study is to verify the efficiency of the micronucleus assay in laboratory,using erythrocytes of the tilapia specie (oreochromis mossambicus) as genotoxicity biomarker. in the present study,the genotoxic potential of pesticides was carried out in the peripheral blood erythrocytes of fish (oreochromis mossambicus) using micronucleus (mn) assay. different doses of organophosphate pesticides (chlorpyrifos and malathion),synthetic pyrethroid pesticide (cypermethrin,lambda-cyhalothrin) and herbicide were injected intraperetonially and specimen were sacrificed after 24 and 48 h. peripheral blood samples smears were stained with giemsa,mn frequencies were counted and statistically analyzed. our results revealed significant dose dependent increase in the frequencies of micronuclei in pesticide treated fish as compare to control. the highest mn frequencies were recorded after 48 h cypermethrin exposure and the lowest mn frequencies were recorded after 48 h buctril exposure. the genotoxicity of pesticides on fish at 48 h exposure in the present study is found to be in the order of cypermethrin,chlorpyrifos,malathion,lambda-cyhalothrin and buctril,in peripheral blood erythrocytes. result of the present study suggests use of the micronucleus test in fish erythrocyte as a sensitive indicator for evaluation and assessment of the carcinogenic and mutagenic compounds in marine environment. copyright 2016 zoological society of pakistan.