Assessment of heavy metal pollution in Tobruk Bay, Libya: A focus on anthropogenic impacts and pollution indices

Abstract

This study investigates the spatial distribution and ecological risks of heavy metal contamination (Cu, Cd, Zn, Mn, Fe, Pb) in sediments from 14 sites across Tobruk Bay, Libya, during October 2024. Using pollution indices such as Cf, Igeo, and Pi, significant spatial variations were observed, identifying critical contamination hotspots. Iron (Fe), Zinc (Zn), and Cadmium (Cd) were the dominant pollutants, particularly near municipal sewage outfalls and the desalination plant outflow, with Fe and Zn reaching 217,6 mg/kg and 327.5 mg/kg, respectively. Moderate Lead (Pb) and Copper (Cu) contamination was detected near port and refinery zones, while Manganese (Mn) exhibited minimal contamination, likely from natural sources. These findings highlight the urgent need for improved wastewater treatment, stricter industrial discharge regulations, and continuous monitoring to mitigate heavy metal accumulation and protect Tobruk Bay's marine ecosystem.