Spatial variations and potential risks of heavy metals in sediments of Yueqing Bay, China

In this study, we determined the spatial variations and potential risks of heavy metals in the sediments of Yueqing Bay by assessing the relationship between metal concentrations and sediment physiochemical factors. We found higher sediment metal concentrations in the inner bay than in the central and outer bay, particularly with respect to Hg, Cu, and Pb concentrations. According to the sediment quality guidelines, the heavy metals had a toxicity incidence probability of 21%. Assessments of heavy metal contamination using the geo-accumulation index and potential ecological risk index suggest that Cr, As, Pb, and Hg likely pose low ecological risks, while Cu, Zn, and Cd were identified as priority pollutants and may pose moderate ecological risks to the ecosystem. Multivariate statistical analysis inferred the high influence of sediment texture, total organic carbon (TOC), and petroleum hydrocarbons (PHCs) on the distribution and fate of metals in sediment.