The harmful effect of any pollutant which entered into water bodies can be assessed by investigating the health of aquatic fauna. The present investigation was aimed to study the effect of sublethal concentration of chlorpyrifos on glycogen, protein and lipids and nucleic acids contents in different tissues of freshwater cat fish, Heteropneustes fossilis after 24, 48, 72 and 96 hours exposure. The result showed the declined level of glycogen, protein, lipids and nucleic acid contents in the tissues of experimental group of fishes as compared to control. The overall results revealed that sublethal concentration of chlorpyrifos effects on the nucleic acids contents in vital tissues of Heteropneustes fossilis leading to decrease in the content of biomolecules.

Keywords: Chlorpyrifos; Heteropneustes fossilis; Biomolecules; Organophosphrous pesticides.