Influence of pH (5.5, 7.0 and 8.5) and alkalinity (40 to 200 mg/L as CaCO
3) on the accumulation of Pb (NO
3)
2, CdCl
2, H
2O and K
2Cr
2O
7 to
Labeo rohita
(Hamilton) was investigated in the laboratory. Highest accumulation of Pb and Cr in whole fish occurred at pH 5.5 and at alkalinity level of 40 to 46 mg/L as CaCO
3 compared to 7.0 and 8.5. In case of Cd maximum accumulation occurred at pH 7.0 and at alkalinity of 100 mg/L as CaCO
3 than that of pH 5.5 and 8.5 and alkalinity 42 and 156 mg/L as CaCO
3. Maximum accumulation of lead and chromium occurred at total alkalinity level of 40 and 46 mg/L as CaCO
3, respectively while maximum accumulation of cadmium occurred at an alkalinity level of 200 mg/L as CaCO
3. A significant (p<0.05) linear relationship was demonstrated between increasing pH/ alkalinity and decreasing accumulation in Pb and Cr treatment at all exposure period while for Cd there was no significant linear relationship established.