Assessment of Polycyclic Aromatic Hydrocarbons in the Biophysical Environment of Anya-Ogologo River, Rivers State, Nigeria

Abstract

Polycyclic aromatic hydrocarbons (PAHs) pose significant environmental and health risks in the Niger Delta, where oil pollution has degraded aquatic ecosystems. This study assessed Polycyclic aromatic hydrocarbons (PAHs) contamination in the Anya-Ogologo River, Rivers State, Nigeria, focusing on water, sediments, and periwinkles (Tympanotonus fuscatus) to evaluate pollution levels, sources, and human health risks. The study findings revealed severe Polycyclic aromatic hydrocarbons (PAHs) contamination, with total concentrations in water ranging from 0.72 to 8.65 mg/L (exceeding moderate pollution thresholds) and sediments from 1.76 to 8.47 mg/kg. Periwinkles showed bioaccumulation of low-molecularweight Polycyclic aromatic hydrocarbons (PAHs) (0.34 mg/kg). Diagnostic ratios indicated pyrogenic dominance (Phen/Anth >1, Flth/Py >1), with negligible petrogenic input (BaA/Chry = 0). Probabilistic risk assessment estimated elevated cancer risks, particularly for children (ILCR >10^-6^), via dermal and inhalation pathways. Conclusively, the study highlights severe Polycyclic aromatic hydrocarbons (PAHs) pollution in the Anya-Ogologo River, primarily from combustion sources, posing significant ecological and health risks. Urgent remediation and policy interventions are needed to mitigate exposure.