Environmental & Analytical Toxicology

Bioaccumulation of Heavy Metals and Physiological Response in Anabas testudineus on Exposure to Paper Mill Effluent

Abstract

Prasanta Nanda

Bioaccumulation of heavy metals and biochemical response in Anabas testudineus was investigated after exposing it to various concentrations (0 - 40%) of paper mill effluent containing low level toxic metal ions. Maximum amount of zinc was accumulated in gills, however ovary was found to be the main target organ for Zn accumulation based on maximum accumulation factor. The increased content of metal ion in all the tissues at higher exposure level confirms the dose dependent accumulation of metal ion. Zinc accumulation follows the pattern gill> liver> ovary> muscle. Copper accumulation was highest in liver and the order of accumulation follows the trend gill> liver> muscle> ovary. Cadmium bioaccumulation was significantly higher in all the tissues without showing any specific trend. Maximum cadmium and lead accumulation was observed in ovary. The trend of Pb accumulation followed the order ovary> liver> gill> muscle. In terms of the type of metal accumulation in all the tissues together, the trend was Zn> Pb> Cu> Cd while tissue specific total metal accumulation followed gills> liver> ovary> muscle. The result of this study indicates that ovary acts as a major accumulator of heavy metals besides gill and liver in A. testudienus when exposed to paper mill effluent. Hematological parameters viz., Hb, TEC, hematocrit and MCHC showed significant (p<0.05) decrease in the exposed fish in comparison to the control value. While level of glucose (except liver) and protein depleted consistently, cholesterol level showed significant increase in plasma, liver and muscles. Physiological response upon exposure to PME indicates damage of tissues with loss of protein and impaired regulation of metabolic function as indicated by blood parameters.