INTERNATIONAL JOURNAL OF PHARMACY & LIFE SCIENCES (Int. J. of Pharm. Life Sci.) Toxicity Evaluation and Behavioural Studies of Fresh Water Fish Labeo rohita Exposed Tt Cypermethrin (Synthetic Pyrethroid)

A short term definitive test by the static renewal bioassay method was conducted to determine the acute toxicity (LC50) of technical grade pyrethroid insecticide, cypermethrin (10%EC) on the fresh water teleost, Labeo rohita. Fishes were exposed to various concentration of cypermethrin for 96 hours and the percent mortality was recorded. The LC50 value was found to be 0.06µl/L and 1/10 th of LC50 0.006µl/L was selected as sub-lethal concentration (1, 5, 10, 15 days). L. rohita in toxic media exhibited erratic and darting movements with imbalanced swimming activity, which might be due to the malfunctioning of neurotransmitters followed by hyper and hypo opercular activity, loss of equilibrium and mucus secretion all over the body were observed.