Acute toxicity of fenthion to freshwater lamellibranch mollusc, Indonaia caeruleus (Prashad 1918), from Godavari River at Paithan--a biochemical approach.

Abstract

Several studies on insecticides effects on aquatic organisms demonstrate that concentrations which are not sufficient to control many species of crop pests, flies and mosquitoes, nevertheless can kill eggs and larvae of lamellibranch molluscs (Davis 1961), kill or immobilize fishes (Westman and Compton 1960; Butler 1964), decrease the productivity of phytoplankton populations (Butler and Springer 1963), and alter the tissue chemistry in molluscs (Eisler and Weinstein 1967) and fishes (Eisler 1967). Since lamellibranch molluscs have specific ecological adaptations in aquatic ecosystems, they constitute a remarkable component in littoral ecosystems. They are suspension feeders on the primary stages of food chains and influence the organization and functioning of the ecosystems. We have undertaken series of experimental studies to assess the toxicity of widely used organophosphorus insecticides in Maharashtra State, India, such as fenthion, folithion and malathion on different species of lamellibranch molluscs like, Lamellidens corrianus, L. marginalis and Indonaia caeruleus from Godavari river at Paithan. Few studies of this nature have been conducted on lamellibranch molluscs (Akarte et al. 1985). Hence, the present study is directed to understand the effect of fenthion (lebaycid 1000 w/w) on biochemical composition of I. caeruleus.