Assessment of polycyclic aromatic hydrocarbons (PAHs) in Shueib Dam sediments in Jordan: Distribution, sources, and potential health risks

This study evaluated 22 surface sediment samples for the presence, distribution, and health risks associated with 16 priority polycyclic aromatic hydrocarbons (PAHs). Measurements of the total PAHs concentration (Σ PAHs) showed notable spatial variability, ranging from 314.3 ± 3.0 µg·kg–1 (SH14) to 1,682.8 ± 7.2 µg·kg–1 (SH3). Across all sites, phenanthrene was the most prevalent compound, with a 100% occurrence. Low-molecular-weight PAHs were the predominant compounds in most of the samples, whereas high-molecular-weight and carcinogenic PAHs (cPAHs; for example, benzo[a]pyrene, dibenz [a, h] anthracene) were found in certain samples, including hotspots (SH7 and SH13), indicating mixed sources of localized pyrogenic and petrogenic inputs. For both adults and children, non-carcinogenic risk estimates (Hazard Index) were below 1, indicating minimal systemic toxicity. However, at many sites (SH13, SH10, and SH18) for both age groups, as well as at seven more sites for children, the carcinogenicity threshold (1 × 10–4) was exceeded. For both adults and children, ingestion was responsible for 82–87% of the estimated cancer risk. The equilibrium release of PAHs into water in dams, which are mostly used for irrigation, could pose health risks.