Published Paper Details:

The organophosphorus insecticide, Nuvan is widely used in agricultural field and private industrial premises to control pests, easily accumulates in aquatic ecosystems and exerts toxic effects on aquatic animals. The study aimed to evaluate the acute toxicity (LC50) of Nuvan on Anabas testudineus. Anabas testudineus were exposed to different concentrations of nuvan ranging from 0.00025 ppm to 2.048 ppm with parallel untreated control. At the doses of 0.0005 ppm, 0.001 ppm, 0.002 ppm, and 0.004 ppm 40%, 50%, 70%, and 90% mortality of Anabas testudineus were observed within 96 hrs, respectively, whereas, 100% mortality was observed at doses above 0.008 ppm. Based on probit analysis, the LC50 value of diazinon for 96 hrs of exposure on Anabas testudineus was found as 0.001 ppm. During the exposure trial several behavioral alterations including restlessness, sudden and quick movements, loss of equilibrium, increased opercular activities and paralysis were observed in the fish. The present study demonstrated that Nuvan is highly toxic especially to Anabas testudineus and thus, indiscriminate use of this insecticide in the agriculture and industrial sectors should be strictly controlled.