Bioaccumulation and elimination of Endosulfan in zebra fish (Brachydanio rerio).

The bioaccumulation and elimination of endosulfan in zebra fish (Brachydanio rerio) were investigated in a semi-static bioassay. The pesticide mean concentration in water was 03ug litre(-1) and the level of endosulfan residues (x(alfa)+B(beta)-isomers+endosulfan sulfate) in the exposed fish at day 21 was 0.81 (+-0.12)ug g(-1) body weight. The estimated value of the bioconcentration factor (BCF) was 2650 (+-441), the total endosulfan residues being eliminated with a biological half-life of four days. Histopathological studies showed predominantly lipid accumulation in the liver and necrotic focus in the gills of exposed fish.