Abstract
The river Ganga is considered sacred and serves as life line for a large number of the population in India. Along with hundreds of millions of peoples, the river basin nurtures a diverse assembly of aquatic including rare and threatened species. These include Dolphins, Otters, ghariyals, crocodiles, fresh water turtles and several species of fresh water fishes. During the last few decades, several anthropogenic activities however have generated huge transformations in the river ecosystem. Rapid urbanization and industrialization contribute heavy pollution to the water. Industrial effluents and sewage entering the river water is one of the prime sources of toxicity, which endangers aquatic biota and deteriorates water quality. In Kanpur alone, tanning, dyeing and paint industries are the major sources of Ganga water pollution. High level of chromium (Cr) has been reported in water because of extensive use of Cr as tanning agent by tanneries. Cr impairs the aquatic environment due to its heavy toxic effects on aquatic life including native fishes. It gets accumulate in the fish’s body, causes reproductive and metabolic dysfunction and subsequently transferred to the higher trophic level. Toxicity of Cr in fish leads to severe disturbance in immunological, haematological, biochemical, neurological, enzymatic and reproductive parameters. In this review article, toxic effects of Cr on freshwater fishes of river Ganga in Kanpur have been discussed.

Key words: River Ganga, Kanpur, Fish, Tanneries, Industrial waste, Chromium toxicity