Histopathology and bioaccumulation of heavy metals (Cr, Ni and Pb) in fish (Channa striatus and Heteropneustes fossilis) tissue: a study for toxicity and ecological impacts.

Abstract: The water samples were collected from the 22 km segment III of Yamuna River from Okhla barrage. This segment receives water from 17 sewage drains of Delhi, Western Yamuna Canal (WYC), upper Ganga canal via Najafgarh drain and Hindon cut canal. Hence, the water samples collected were used to determine the presence of Chromium, Nickel and Lead through Atomic Absorption Spectrophotometry. The concentration of these heavy metals were much above the maximum permissible limits set by WHO. This was bound to have its influence on the riverine flora and fauna. To evaluate this, two popularly consumed fish species such as Channa striatus and Heteropneustes fossilis were caught and the bioaccumulation of these heavy metals were estimated in different organs (liver, kidney, gill and muscle). It was found that Cr accumulated the most in these organs (gill being most influenced) in both the species. The accumulation of all these heavy metals were above MPL set by World Health Organisation (WHO) and Food and Drug Administration (FDA). Histopathology was also conducted where heavy damages were observed in both liver and kidney of both the species.