Polycyclic aromatic hydrocarbons (PAHs) are a class of organic compounds that contain multiple fused aromatic rings. They are formed during the incomplete combustion of organic matter, such as fossil fuels, wood, and tobacco, and are also found in some industrial processes and pollution sources. PAHs are of interest in environmental and health research due to their potential toxicity and carcinogenicity. They are known to be harmful to human health and the environment, and have been linked to various health problems, including cancer, respiratory issues, and reproductive issues. Researchers study PAHs in various contexts, including their sources and distribution in the environment, their pathways of exposure and bioaccumulation, their toxicological effects, and strategies for mitigation and remediation. PAH research is important for understanding and managing the risks associated with these compounds and protecting human and environmental health.