Toxicological and physiological impact and bioremediation strategies for polycyclic aromatic hydrocarbons (PAHs)

Polycyclic aromatic hydrocarbons (PAHs) are persistent organic pollutants composed of fused benzene rings, released into the environment through fossil fuel combustion, industrial processes, forest fires, and natural events. Due to their hydrophobicity and low solubility, PAHs are resistant to degradation and accumulate in ecosystems. Recognized as mutagenic and carcinogenic, PAHs pose serious risks to human and environmental health. In aquatic systems, they can harm microbial, plant, and animal life by disrupting growth, metabolism, genetic stability, and membrane integrity. This review explores the extent of PAH contamination in aquatic environments, focusing on their toxic effects on both invertebrate and vertebrate aquatic species, particularly ichthyofauna. It also discusses microbial and plant-based degradation processes and evaluates bioremediation strategies aimed at reducing PAH concentrations and associated toxicity. Certain microorganisms and plants have adapted mechanisms to break down PAHs, and studies show that their combined action can accelerate pollutant degradation. By highlighting these natural remediation pathways, this review emphasizes the importance of sustainable strategies to mitigate PAH impacts on aquatic ecosystems and protect overall ecosystem health.