Assessment of biochemical changes due to sub-lethal chronic toxicity in Labeo rohita exposed to Chloropyrifos and Neem oil.

Abstract

Chloropyrifos, an organophosphate pesticide which is wide used across the state, while on the other hand use of Neem oil as biopesticide is a restricted affair. A detailed comparative toxicological implication of Chloropyrifos and Neem oil is lacking. Thus, this study is conceptualized to determine the LC50 values of Chloropyrifos (Commercial grade named as Dursban) and Neem oil     on Labeo rohita (a well-known adequately consumed Indian major carp) and to further investigate the biochemical effects of two sub-lethal doses      1/2 of LC50 (0.021 mg/l) and 1/4th of LC50 (0.0105mg/l) of Chloropyrifos           along with ½ of LC50 (22.32 mg/l) and ¼ th of LC50 (11.16mg/l) Neem oil. Among the biochemical parameters tested Serum glucose, cholesterol, triglycerides increased significantly (p < 0.0001) for both the sub-lethal doses of Chloropyrifos and Neem oil for a chronic exposure of 30 days in a dose and exposure dependent relationship but the level of increase is more in case of Chloropyrifos than Neem oil. Total serum protein and Liver glycogen showed a marked decline (p < 0.0001) for both the sub-lethal doses of Chloropyrifos and Neem oil, but the decline is more prominent in Chloropyrifos than Neem oil when exposed for 30 days of chronic toxicity. Overall result of the study indicates that Chloropyrifos is more harmful than Neem oil for non-target aquatic organism like fishes, hence care should be taken to manage contaminated agricultural run-off into the nearby water bodies serving as culture hub of fishes like labeo rohita.