Health and Ecological Risk Assessments of Some Heavy Metals (Cr, Ni, Pb, Cu and Zn) in the Sediments of Darbandikhan Reservoir, Iraq

Abstract

This study aimed to investigate the concentrations of some heavy metals HMs in the bottom sediments of Darbandikhan Reservoir in North of Iraq. This study evaluated the contamination of sediments with heavy metals HMs and their ecological risk levels as well as their potential effects on human health. Among the examined metals: Ni, Cr and Zn exceeded the background values in most of the sampling stations. The Enrichment factor EF for the examined HMs in the sediment of the study area showed an order of Ni > Cr > Zn > Pb > Cu. Also, the Potential ecological risk Er mean values of Ni, Cu, Cr, Pb and Zn were 13.64, 2.75, 2.17, 2.02 and 1.01 respectively. Moreover, the mean value of contamination factor CF for Ni was 2.73, which shows that the sediment in Darbandikhan Reservior is in the status of reasonable to significant degree of contamination. The values of hazard quotient HQ for Cr, Zn, and Ni ranged from 1.7x10^− 7 to 8.7x10^− 4, and 8.1x10^− 7 to 2.1x10^− 1 for adults and children, respectively, which indicates that the examined HMs would not cause non-carcinogenic risk for children and adults. While, the values of CR for Cr, Ni and Zn on children via accidental ingestion were 2.6x10^− 5, 8.3x10^− 5 and 4.34x10^− 7, respectively; and those of adult were 5.58x10^− 5, 1.78x10^− 4 and 9.3x10^− 7, respectively. This indicated that the CR levels caused by Ni and Cr were not acceptable and may pose risks of cancer in case of accidental ingestion.