Abstract:
Polycyclic aromatic hydrocarbons (PAHs) are a class of ubiquitous persistent organic pollutants in aquatic environments that are characterized by high environmental persistence, strong bioaccumulation potential, and diverse toxicological effects. Consequently, they have become a major concern in water pollution control and ecological risk assessment. Although substantial progress has been made in understanding the occurrence, ecological impacts, and remediation of PAHs, critical knowledge gaps remain regarding their cross-media transport and transformation, the environmental risks associated with PAH derivatives, and the efficient removal of high-molecular-weight PAHs. This review summarizes recent advances in the distribution characteristics, environmental fate, adverse effects, and remediation strategies of PAHs in aquatic environments. Available evidence indicates that PAHs exhibit pronounced heterogeneity among environmental compartments, with sediments and benthic deposits acting as major reservoirs and potential secondary sources. The ecological risks of PAHs extend beyond their well-established carcinogenic, mutagenic, and teratogenic effects to include oxidative stress, ecological dysfunction, food-web transfer, and enhanced toxicity arising from derivative compounds. Current remediation approaches have evolved into diversified frameworks involving microbial degradation, advanced oxidation processes, and constructed wetlands. Nevertheless, the effective treatment of high-molecular-weight PAHs and complex co-contaminated systems remains a significant challenge. Future research should focus on elucidating the environmental behavior of PAHs and their derivatives, improving risk assessment under complex pollution scenarios, and developing integrated remediation technologies to support more effective prevention and management of PAH contamination in aquatic environments.