Bioaccumulation of cadmium in the organs of freshwater fish Heteropneustes fossilis (Bloch, 1794)

Bioaccumulation of cadmium in various organs such as gills, kidneys, liver, skin and muscle of the freshwater fish Heteropneustes fossilis exposed to sublethal concentration of cadmium chloride (12 ppm) has been studied for a period of 45 days. Cadmium was assayed using atomic absorption spectrophotometry and the results were given as mu g g(-1) dry wt. The accumulation of the heavy metal gradually increased in the order of gills > kidneys > liver > skin > muscle. The rate of accumulation which varied from tissue to tissue, may be attributed to the proximity of the tissues to the toxicant medium, their structural and functional organization and presence of various molecules having high affinity to cadmium.