Heavy metals in sediments of an urban river at the vicinity of tannery industries in Bangladesh: a preliminary study for ecological and human health risk

This study was conducted to measure the concentration of heavy metals and to examine their allied ecological and health risk from the sediments of an urban river adjacent to the tannery industrial park. In this study, atomic absorption spectrophotometer was used to quantify the concentration of lead (Pb), cadmium (Cd), copper (Cu), chromium (Cr), iron (Fe), manganese (Mn), nickel (Ni) and zinc (Zn) in sediments. The mean concentrations of Pb, Cd, Cu, Cr, Fe, Mn, Ni and Zn in sediments were 15.4, 0.73, 6.8, 64.7, 305.2, 19.9, 18.2 and 7.3 mg/kg, respectively. According to the Sediment Quality Guideline, sediments from Dhaleshwari River were not polluted by Pb, Cu, Mn and Zn but moderately polluted by Cd and Ni and heavily polluted with Cr and Fe. Moreover, sediment contamination factor (CF), pollution load index (PLI) and geo-accumulation index (I _geo) demonstrated that sediments from the study river were heavily contaminated by Cd and Cr. Furthermore, potential ecological risk showed high risk of Cd and Cr. Hazard quotient (HQ) and Hazard index (HI) values showed heavily contaminated for Cr and moderately contaminated for Pb for both adult and children. In view of the potential non-carcinogenic human health risk showed heavily contaminated for Cr and moderately contaminated for Pb in this study area.