Freshwater snake headed fish Channa punctatus (Bloch), was exposed to sub-lethal concentration (1/10th of 96 h LC50) of Dicofol 18.5% EC for 24, 48, 72, 96 and 30 days and the consequential impact on hormonal activity was studied. The LC50 values calculated for 24, 48, 72, 96 h using Finney’s (1972) probit analysis and were 0.075, 0.075, 0.72, and 0.72 ppm respectively. In the present study it was observed that, short-term dicofol exposure (96 h) did not exert appreciable changes in Estradiol and Testosterone levels in sub-lethal exposure. On the contrary, prolonged dicofol exposure (30Days) significantly decreased LH, FSH, TSH, T4, Testosterone and Progesterone levels in dose and time-dependent manner. The decrease in hormone action may be due to the interference of the test toxicant with the synthesis, transport, metabolism and elimination of hormones, thereby decreasing the concentration of natural hormones. The results obtained were in corroborative with the earlier reports and the discussed at length with the available literature
