Determination of 96 h LC50 Value and Acute Toxicity of Marshal (Carbosulfan 25%EC) on Thyroid and Reproductive Hormones of Labeo rohita (Hamilton)

Contamination of water bodies by pesticides can lead to fish death and reduced fish productivity etc. which can affect humans consuming these fishes as a source of protein. The present study was designed to determine the 96h LC50 value of a carbamate pesticide, Marshal (Carbosulfan 25%EC) and to investigate effects of this pesticide on the thyroid and reproductive hormones profile of Indian major carp Labeo rohita (Hamilton). The present study indicates that Marshal has potential hormonal stress on Labeo rohita. The mortality data obtained were analyzed by SPSS 16.0 based on Finney’s Probit Analysis Statistical method. The 96h LC50 value for Marshal was found to be 10 ?l/L. Effects of this carbamate pesticide on serum T3, T4 and TSH, testosterone and estradiol were investigated at sub-lethal concentration. Serum T3, T4 and TSH were studied for 96 h and testosterone and estradiol for 4 days and 15 days. These parameters (except TSH) decrease after exposure of the fish to pesticide.