Metal pollution in sediments along the Montenegrin coast, Adriatic Sea: a risk analysis

Abstract

Purpose

The study aims to assess the ecological risks posed by metal contamination in Montenegrin marine sediments, focusing on both Boka Kotorska Bay and the coastal part of the open sea. By analyzing metal concentrations and identifying potential pollution hotspots and sources, the research seeks to contribute to a better understanding of the escalating threats to coastal regions and their ecological implications due to anthropogenic activities.

Methods

Total concentrations of Fe, Mn, Cr, Ni, Zn, Cu, Pb, As, Hg, and Cd were determined in surface sediment samples collected from 10 sites along the Montenegrin coast, targeting areas influenced with different sources and levels of anthropogenic pollution. Statistical analysis was performed, and various pollution indices (contamination factor (C_f), geo-accumulation index (Igeo), potential ecological risk factor (\({E}_{r}^{i})\), pollution load index (PLI), risk index (RI), mean ERM quotient (MERMQ), and toxic risk index (TRI)) were calculated to assess contamination status, severity of pollution, and potential ecological risks.

Results

The results showed varying levels of metals, with elevated concentrations of Fe, Mn, Ni, and Cr at location S10 (Ada Bojana), and higher Cu, Pb, Hg, and Zn levels at S5 (Bijela). C_f and Igeo values indicated mainly moderate to considerable pollution, with Pb concentrations of particular concern. Ecological risks were posed by Hg and, in some cases, Cd, while Ni concentrations presented the highest toxic risk to marine organisms according to TRI_i values. Overall, pollution was present in the entire area, with mainly moderate ecological risk according to RI values, but considerable to very high toxic risks highlighted by MERMQ and TRI values at various locations.

Conclusion

This study revealed overall pollution presence in surface sediments along the Montenegrin coast, predominantly associated with anthropogenic sources, thereby posing potential ecological risks, particularly in Boka Kotorska Bay and at S10 (Ada Bojana). The obtained results highlighted the need for continued monitoring and management strategies to mitigate environmental impacts.