Environmental risk of trace metals and metalloids in estuarine sediments: An example from Southampton Water, UK

Industrial and commercial port activities are widely recognized worldwide as an important source of pollution to proximal estuaries. In this study, we analysed geochemical and sedimentological parameters including major and trace elements, organic matter and sediment texture in surface sediments from the estuarine environment of Southampton Water, U.K. Using these data, and multivariate statistical tools [correlation, factor and cluster analysis and pollution indices such as Enrichment Factor (EF), Pollution Load Index (PLI) and the Adverse Effect Index (AEI)], we examine sedimentary trace metal and metalloid contamination, contamination sources, and potential biological impacts of the contamination present. The geochemical data, multivariate statistical analysis and pollution indices indicate that the spatial distribution of trace metals and metalloids is influenced by both sediment composition (and mixing) and anthropogenic activities. Most trace metal and metalloid concentrations are close to local geological background levels, except for Cu, Zn and Pb. The spatial distribution of these elements indicates that the Exxon oil refinery, Southampton port, local marinas and runoff from domestic and industrial activities act effectively as point sources of these elements. Pollution indices calculations highlight a degraded environment as a result of these pollutants, and further work is needed to assess the current impact of trace metals and metalloids on local ecology.

Automated summary

Industrial and commercial port activities are recognized as a significant source of pollution to estuaries. This study focuses on the estuarine environment of Southampton Water, UK, investigating the contamination of trace metals and metalloids in sediments, their sources, and potential biological impacts. The findings suggest that the distribution of these contaminants is influenced by sediment composition and anthropogenic activities, with Cu, Zn, and Pb concentrations exceeding background levels. The Exxon oil refinery, Southampton port, marinas, and industrial and domestic runoff emerge as notable point sources of these elements. Pollution indices calculations highlight the environmental degradation caused by these pollutants, calling for further research to assess the current impact on the local ecology.