What are polycyclic aromatic hyrdocarbons?
Polycyclic aromatic hydrocarbons (PAHs) are a group of chemicals formed by incomplete combustion of organic materials, such as fossil fuels, municipal and industrial waste, wood, tobacco, and meat. Large quantities of PAHs are released during such natural events as volcanic eruptions and forest fires. However, many human activities, such as burning coal, oil, and wood for heat and gas-powered motor travel, also release PAHs into the environment. Grilling food and smoking also create PAHs, albeit in smaller quantities. PAHs are found in asphalt, creosote, coal tar pitch, roofing tar, coal, and crude oil. A few PAHs are used in medicines, plastics, dyes, and pesticides. PAHs generally occur as complex mixtures of chemicals.
