Accumulation of Heavy Metal in Water and Certain Freshwater Fishes of Bellandur Lake, Karnataka

Abstract

Human activity has continuously concerned the natural environment, particularly the aquatic ecosystems. The use of heavy metals in the industry has led to general environmental contamination. Some of these compounds are the object of study because of their toxicity and ubiquity. Moreover, they are known to remain stable in the aquatic environment. Trace metals are regarded as serious pollutants of the aquatic environment because of their toxicity, persistence, non-biodegradability and tendency to accumulate in aquatic organisms. A chemical can build up to a potentially harmful level in animal tissues as its bioaccumulation need not elicit a biological response. In the present investigation, toxicology about aquatic animals has become a key subject in water pollution studies. Accumulation of the heavy metals like Zn, Fe, Ni, Pb, Cd and Cu in the gut-free body, liver and gills of three species of the fish, Notopterus monopteros, Oreochromis mossambicus and Mystus vittatus, inhabiting the Bellandur lake, Bangalore was observed. The results showed that these metals were common throughout the study area, but the metal concentrations in the water samples were below the detection levels (BDL). Accumulation of Zn, Fe, Ni, Pb, Cd and Cu was determined in fish tissues (whole fish, liver and gill) and it was found to have reached a biologically magnified level in fish tissues. Interestingly, the metal concentration levels in fish tissue samples were elevated than those of water.