Assessment of heavy metal levels in sediment samples of Kapulukaya Dam Lake (Kirikkale) and lower catchment area

In this study, the concentrations of 13 elements (Al, Fe, Mn, Cr, Ni, Zn, Co, As, Pb, Cu, Mo, Hg, and Cd) were determined in the sediments of three different sites in the Kapulukaya Dam Lake between May 2007 and November 2008. They ranged from 1.47 to 4.64 for Al, 0.92 to 3.48 for Fe (in percent), 326.60 to 1053.00 for Mn, 98.00 to 1,116.00 for Cr, 24.70 to 127.10 for Ni, 14.80 to 124.20 for Zn, 11.0 to 43.20 for Co, 5.00 to 29.30 for Cu, 9.10 to 69.70 for As, 8.60 to 34.00 for Pb, 2.50 to 5.20 for Mo, 1.00 to 1.60 for Hg, and 0.50 to1.80 for Cd in microgram per gram dry weight sediment. The contamination degree of the sediment was assessed on the basis of enrichment factor and corresponding sediment quality guideline. The calculated enrichment factors (EF, measured metal vs. background concentrations) indicated that the effect of man-made activities on the occurrence of concentrations could be accounted for the majority of heavy metals namely Mn, As, Ni, Cu, Zn, Cr, Co, Mo, and Cd, whereas such affect was not detected for Hg and Pb. The maximum values of the EF were represented by As, minimum values by Hg at all sites. Mean EF values were 36.60 and 0.70 for As and Hg, respectively. This study has clearly assessed a certain level of heavy metal pollution in the region, based particularly on the findings from sediment.