Heavy Metals in Salt Marsh Sediments of Porteresia Bed along the Karnafully River Coast, Chittagong

Abstract

Heavy metal (Cu, Zn, Cd, Pb and Fe) concentrations in salt marsh sediments of the Karnafully River coast were investigated in this study. Sediment samples of four different sites were analysed for selected heavy metals by AAS (atomic absorption spectrophotometry). The mean values of heavy metals were 45.79 µg/g for Cu, 105.0 µg/g for Zn, 0.43 µg/g for Cd, 26.70 µg/g for Pb and 3297.38 µg/g for Fe in this study. It is observed that Pb and Cu have positive correlations (r = 0.370, P < 0.05) and Fe and Zn have negative correlations (r = -0.729, P < 0.05) in the correlation matrix. Except Fe, all the metals were found at contamination levels which may indicate a recent and continuous contamination from domestic and industrial discharges. The results of sediment samples showed that the Karnafully River coast is facing heavy metal pollution.