Source and pollution assessment of heavy metals in surface sediments of Laoshan Bay, South Yellow Sea, China

Abstract

A total of 25 surface sediment samples collected from Laoshan Bay, China, during 2018, were analyzed for heavy metal concentrations, sources, and pollution status. The Cu, Zn, and Cr distributions were similar, whereas the distributions of other metals and the total organic carbon (TOC) content were irregular, and high concentrations appeared in one or two areas. Pearson's correlation coefficient, the geoaccumulation index, and principal component analysis were used to distinguish the sources and assess the pollution risk of heavy metals. The results showed that the surface sediments in Laoshan Bay were not polluted by Cu, Zn, Cr, or As, but were unpolluted to strongly polluted with Pb, Cd, and Hg. Cu, Zn, Cr, and As were mainly derived from natural sources; Pb and Cd were mainly derived from anthropogenic sources; and Hg may have had compound sources.