CONCENTRATION OF HEAVY METALS IN DRINKING WATER OF DIFFERENT LOCALITIES IN DISTRICT EAST KARACHI
Abstract
Background: Several heavy metals are present in drinking water that play important roles in the body provided theirlevel remains within the specified range recommended by WHO. But now due to the industriali7ation and rapidurbanization, the problems of pollution have surfaced. This study was designed to ascertain the contents of some heavymetals and then their variations if any in drinking water in different localities of district East of Karachi, Pakistan.Methods: Drinking water samples were collected from different sources and localities of district East of Karachi. Theconcentration of the heavy metals i.e. Lead, Arsenic. Copper, Iron. Mercury, Chromium, Manganese, Nickel,Cadmium and Zinc were determined by Atomic Absorption Spectrophotometry. Phi was estimated by pH meter. Totaldissolved solids (TDS) were calculated by formula. These concentrations of heavy metals, pH and TDS werecompared with the standards set by WHO. Results: Concentrations of lead and nickel were found to be significantlyelevated as compared to WHO recommended levels in all the three sources of water (Piped water. Hand pump waterand Tanker water supply). Chromium was found to be raised in hand pump water. Arsenic and Mercury were notdetected in any source of water. Copper, iron, manganese, cadmium and zinc were found to be within the safe limitsin all the three sources of water. pH was found to be within the range of WHO recommended level in all the threesources of water. TDS was found to be elevated in hand pump water and tanker water. Conclusion: Concentrationsof lead and nickel were found to be significantly elevated as compared to WHO recommended levels in all the threesources of water in district East of Karachi.References
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