Assessment of heavy metal contamination in urban river sediments in the Jiaozhou Bay catchment, Qingdao, China

- Heavy metal concentrations in urban rivers around Jiaozhou Bay were analyzed.
- The sediments are characterized by high levels of heavy metals.
- The anthropogenic inputs of Cd, Pb, and As are the most significant.
- Heavy contamination occurred in the eastern Jiaozhou Bay catchment.

Selected heavy metals (Cu, Pb, Zn, Cr, Cd, and As) in 47 river sediment samples collected in the Jiaozhou Bay (JZB) catchment were evaluated to assess their spatial distributions and the potential ecological risks. The heavy metal concentrations in the sediments ranged from 4.5-178.7 mg kg− 1 for Cu, 8.2-65.8 mg kg− 1 for Pb, 8.2-325.7 mg kg− 1 for Zn, 12.2-185.5 mg kg− 1 for Cr, 0.013-1.486 mg kg− 1 for Cd, and 1.2-20.6 mg kg− 1 for As. The results showed that the overall sediment quality in the area generally met the China Marine Sediment Quality criteria. Based on the effect-range classification (the threshold effect level (TEL)/probable effect level (PEL) Sediment Quality Guidelines, Cu, Cr, and As were likely to have adverse biological impacts on local aquatic ecosystems. The geoaccumulation index (Igeo), enrichment factor (EF), contamination factor (CF), and pollution load index (PLI) values suggested that elevated levels of Cd, As, and Pb contamination occurred in the eastern JZB catchment (i.e., Hongjiang River, Moshui River, Baisha River, Loushan River, Licun River, and Haipo River). This study presents the current state of the sediment quality in the JZB catchment. The results may assist in the definition of future coastal and river management measures specifically targeted at monitoring heavy metal contamination.