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