Distribution and Pollution Assessment of Heavy Metals in Surface Sediments of Jiaozhou Bay

Surface sediment samples were collected from eleven stations of Jiaozhou Bay,the Yellow Sea in July 2009,and concentrations of eight heavy metals were measured.Effects of the construction of Jiaozhou Bay Bridge on metal distribution and contamination were evaluated.The concentrations of heavy metals were generally low in this survey,in which the average concentrations of Hg,Cu,Pb,Zn,Cd,Ni,Co,Mn were 0.031,19.05,12.7,51.14,0.055,17.31,8.24,775 mg/kg,respectively.The pollution levels and potential ecological risks of heavy metals were evaluated by Geoaccumulation index and Hankanson's method.The results displayed that almost all the metals were at low pollution levels except for Hg.The heavy metal distribution among stations in this survey suggested the disturbance of sediments by the construction of oversea bridge,which might increase the risk of cross-contamination of pollutants in sediments.