Chlorpyrifos (CPF) is one of the most common insecticides found in freshwater ecosystem, and has been detected in agriculture and fish products worldwide. Pesticides affects the aquatic organism both directly and indirectly. Agricultural runoff has a direct entry path, whereas food chain consumption has an indirect entry path. The present study was conducted to assess the histopathological alterations in the kidney and liver of Cirrhinus mrigala and Labeo rohita treated with various concentration of chlorpyrifos. Fishes were divided into four                 groups for experiment. Group I taken as control group. Group II, III and IV were exposed to 4.0 mg/L, 4.5 mg/L and 5.0 mg/L respectively solution of chlorpyrifos for short term experiment (96 h). The histopathological changes in kidney and liver was observed after exposure of chlorpyrifos at 24, 48, 72 and 96 hours. During the exposure trial several behavioral changes including loss of equilibrium, increased opercular movement, rapid gulping of water and changes in skin colouration were observed in the fish.

Key words: Fishes, Cirrhinus mrigala, Labeo rohita, Kidney, Liver, Chlorpyrifos, Histopathology