Studies on the acute toxicity of some heavy metals to an Indian freshwater pond snail Viviparus bengalensis L

Abstract

The Indian freshwater pond snail Viviparus bengalensis L. was exposed to lethal concentrations of selected heavy metals. In the static bioassays the 96 hr LC50 values in ppm were 0.088 for copper; 2.83 for zinc; 6.27 for chromium; 8.40 for cadmium and 39.83 for nickel. Decreased pH values were recorded at some of the higher concentrations of zinc, nickel and cadmium solutions. At the close of 24 hr of exposure zinc and cadmium solutions showed white precipitation and milky nature. The results of this experiment indicate that the rank order of these heavy metals was Cu > Zn > Cr > Cd > Ni.