Heavy metals in the sediments of Laoshan Bay, China: Distribution and contamination assessment

We analyzed total organic carbon (TOC), total nitrogen (TN), and heavy metals in 58 sediment samples from the Laoshan Bay, China. TOC and TN results identified marine primary production as the dominant source for organic matter, and the weak correlations between TOC, TN, and heavy metals indicated the terrestrial origin of heavy metals. Cd showed insignificant correlations with other metals, which suggests that agriculture production is the main anthropogenic activity affecting the distribution of Cd. Pb contamination in past 50 years was likely to have occurred because of fossil fuel combustion. Despite 210Pb dating, it was still difficult to trace the contamination condition over interannual variations. Nonetheless, these results provide data for monitoring Pb contamination. As Laoshan Bay is an important economic area, it would be beneficial to conduct further studies to determine the sources and degree of contamination for each heavy metal.

Automated summary

Analysis of sediment samples from Laoshan Bay, China, showed marine primary production as the main source of organic matter, while heavy metals originated from the terrestrial environment. Cd is mainly influenced by agricultural activities, while Pb contamination is likely due to fossil fuel combustion and difficult to trace over interannual variations.