Analysis of suppressive effects of pesticide triazophos on leucocyte immune responses in a teleost, .

Triazophos is a commonly used organophosphate insecticide, which inhibits the acetylcholinesterase enzyme and causes paralysis and death of insects. Impact of the pesticides on immunity has scarcely been investigated, especially in fishes. The present study was designed to analyze the immunotoxic role of triazophos exposure to the leucocytes in freshwater teleost, . Triazophos, at concentrations of 0.1, 0.5, and 1 µg ml, was used to study leucocyte phagocytosis, superoxide production, nitrite release, and lymphocyte proliferation. Dose-dependent suppression of various immune responses was observed. Nitrite release and superoxide production by leucocytes were reduced in cultures incubated with triazophos. Mitogen-induced lymphocyte proliferation was significantly reduced at 0.5 and 1 µg ml but not at 0.1 µg ml concentration of pesticide. The biphasic suppressive effect was also discovered while evaluating phagocytic response. These investigations describe the effects of pesticide on immune responses in , which are helpful in understanding the immunotoxicity in fish. Substantially more researches are required to help design the measures to combat ecotoxicity in freshwater bodies.