Int. J. Biosci.18( 3), 164-181, March 2021
Dhaka, one of the megacities in the world is situated at the bank of the Buriganga River. This river is flowing along the southeastern part of the megacity. The Buriganga River had a large contribution as an alternative source of water for the capital city of Bangladesh. But, at present the river water becomes polluted through various means viz. chemical wastes discharging, untreated industrial effluents disposal, human activities, sewage disposal and other solid wastes and consequently, it has been treated as a dead river. Rapid industrialization, urbanization and climate changes have put a negative impact on the soil, water and sediment quality of the Buriganga river for multifarious purposes. Typical researches on heavy metals contamination on the effluent of tannery, textile and dye industries, status and health risk assessment of heavy metals in water, sediment and fishes of Buriganga River, show that concentration of heavy metal is increasing day by day, especially in industrial areas. The heavy metals that are polluting the water of the Buriganga river are Chromium (Cr), Copper (Cu), Arsenic (As), Nickel (Ni), Lead (Pb), Cadmium (Cd), Manganese (Mn), Cobalt (Co), Zinc (Zn) and Iron (Fe). This review aims to represent the remarkable findings of metal pollution (exceeding water and sediments quality parameters as well as detrimental ecotoxicological threats and potential health risks) from the previously conducted researches on this critical urban river in this field and to make the dedicated researchers conscious about the present heavy metal’s contamination background of the Buriganga River.
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