Polycyclic aromatic hydrocarbons (PAHs) are a group of organic compounds made up of multiple fused aromatic rings. They are primarily formed during the incomplete combustion of organic materials, such as fossil fuels, wood, and tobacco. PAHs can be found in various environments, including air, soil, and water, and are often associated with industrial processes and vehicle emissions. Due to their potential health risks, PAHs are considered environmental pollutants. Some PAHs are known to be carcinogenic, meaning they can contribute to the development of cancer in humans. Regulatory agencies monitor PAH levels to protect public health and the environment, emphasizing the importance of reducing exposure to these harmful substances.