polycyclic aromatic hydrocarbon
(pah-lee-SY-klik AYR-oh-MA-tik HY-droh-KAR-bun)
A type of chemical formed when coal, oil, gas, garbage, tobacco, meat, and other substances are burned. These chemicals are also made for use in many products, including coal tar, creosote, roofing tar, pesticides, mothballs, dandruff shampoos, and some medicines. Being exposed to one of these chemicals over a long time may cause cancer. Also called PAH.