Title: Environmental Sources, Formation, And Biotransformation Pathways And Health Effects Of Polycyclic Aromatic Hydrocarbons: A Review
Authors: Ampaire Wycliffe , Kerebba Nasifu, Twinomuhwezi Hannington, Wanasolo William
Volume: 9
Issue: 10
Pages: 52-67
Publication Date: 2025/10/28
Abstract:
This paper critically reviews the current knowledge on Polycyclic Aromatic Hydrocarbons (PAHs), hazardous organic pollutants mainly produced by the incomplete combustion of organic matter. While PAH distribution in air, soil, and water is relatively well-documented, their behavior in complex systems such as post-wildfire environments and urban runoff remains poorly understood. Key gaps include limited knowledge on PAH transport, transformation, and partitioning among particle sizes, as well as their long-range atmospheric transport and deposition in pristine ecosystems. The review highlights the need to investigate PAH interactions with emerging carbon-based materials such as graphdiyne, particularly their adsorption and desorption dynamics for potential remediation applications. Another critical research gap lies in understanding the bioavailability of both parent and alkylated PAHs in soils and sediments, especially using in vitro digestion models or bioaccumulation studies in aquatic organisms. Additionally, the transformation of PAHs into toxic metabolites for example, hydroxylated PAHs, and their health and ecological impacts remain underexplored. The role of microbial communities in degrading high-molecular-weight PAHs under diverse environmental conditions, both aerobic and anaerobic, also requires further study. Addressing these gaps would provide novel insights into PAH persistence, fate, and risk. The review concludes that effective environmental management and policy formulation depend on identifying PAH sources and adopting multifaceted approaches, including regulatory measures, continuous monitoring, cleaner technologies, public awareness, and community participation.