Toxic effects of sublethal concentrations of diethyl Phthalate on the gills of African catfish (<i>Clarias gariepinus</i>) juveniles

Abstract

An investigation on the effect of Diethyl phthalate (DEP) on the gill of the African catfish Clarias gariepinus was carried out in the laboratory. Seventy-five (75) catfish fingerlings were subjected to continuous exposure to sublethal concentrations of DEP (30, 40, 60 and 80 ìg/L) for a period of four weeks. The gills of the catfish were removed every 15 days for histological examination. The degree of distortion of the gills (heamorrahging of
the gill, continuous degeneration of the gill filaments, disruption of epithelium owing to rapid cell lysis, severe destruction of the lamellae) was proportional to the exposure periods (0, 15 and 30 days) and concentration of the DEP was found to be dose and time dependent which led to asphyxiation and stress in the catfish.