Heavy metals in the surface sediment of Liaodong bay and their potential ecological risk

In order to understand the pollution characteristics of heavy metals in surface sediments of Liaodong bay, the concentrations of heavy metals including Hg, Cu, Pb, Cd, Cr, Zn, As in 33 samples were measured by atomic absorption spectrophotometry and atomic fluorescence spectrometric.The index of geoaccumulation and the potential ecological risk index were then employed to evaluate the pollution degree and potential ecological risk of heavy metals in the sediments.The results indicate that the average contents of Hg, Cu, Pb, Cd, Cr, Zn, As in Liaodong bay are 0.09, 18.81, 20.55, 0.35, 34.16, 52.94, 5.84 mg/kg, respectively.The pollution level of heavy metals in sediment by geoaccumulation index (I_geo) follows the order:Cd > Hg > Cu > Pb > Zn > As > Cr.The potential ecological risk of heavy metals in sediments by the potential ecological risk factors (Erⁱ) follows the order:Hg > Cd > As > Cu > Pb > Cr > Zn.The potential ecological risk of most study area is in the low and medium level, except for 13 stations in the Jinzhou Bay which is in the relatively severe level.