University Of Tehran Press Pollution 2383-451X 12 1 2026 01 01 Assessment of Polycyclic Aromatic Hydrocarbons (PAHs) in Seawater of the Gulf of Tobruk, Libya: Concentrations, Sources, and Environmental Risks 275 287 105152 10.22059/poll.2025.398762.3029 EN Mohamed Abdelaziz Okbah National Institute of Oceanography and Fisheries, NIOF, Cairo, Egypt Maie El-Gammal Environmental Sciences Department, Faculty of Science, Damietta University, Egypt Mohamed Bahnasawi Zoology Department, Faculty of Science, Damietta University, Egypt Abdulali Balal Department of Marine Resources, Faculty of Natural Resources, University of Tobruk, Tobruk, Libya Journal Article 2025 07 17 There is limited data on the levels of polycyclic aromatic hydrocarbons (PAHs) in the waters of the Gulf of Tobruk, Libya. This study aims to establish a monitoring system to assess PAH concentrations, sources, and ecological risks in the region. Water samples were collected from seven sites during summer and winter. The concentrations of 16 PAHs ranged from 62.33 to 454.70 ng/L (Mean: 235.23 ± 152.37 ng/L) in summer and from 79.26 to 473.36 ng/L (Mean: 253.85 ± 151.49 ng/L) in winter, indicating high levels of pollution. Seasonal variations suggest lower PAH concentrations in summer due to differences in industrial activities, urban runoff, and hydrodynamic conditions. PAH diagnostic ratios and principal component analysis (PCA) revealed mixed petrogenic and pyrogenic sources. Tobruk Bay is under high ecological stress from PAH contamination. The ecological risk assessment classified the Gulf of Tobruk as a medium to high-risk area, posing potential harm to aquatic organisms. These findings underscore the need for long-term monitoring and pollution control strategies. https://jpoll.ut.ac.ir/article_105152_e72a9668bb9abffa12dba8a2b124b1b7.pdf