WHAT ARE POLYCYCLIC AROMATIC HYDROCARBONS?
Polycyclic aromatic hydrocarbons are a group of chemicals that occur naturally in coal, crude oil, and gasoline. PAHs are also present in products made from fossil fuels, such as coal-tar pitch, creosote, and asphalt. When coal is converted to natural gas, PAHs can be released. Therefore, some coal-gasification sites may have elevated levels of PAHs. PAHs also can be released into the air during the burning of fossil fuels, garbage, or other organic substances. The less efficient the burning process, the more PAHs are given off. Forest fires and volcanoes produce PAHs naturally. PAHs are found throughout the environment in the air, water, and soil, and can persist in the environment for months or years. Although hundreds of PAHs exist, some of the more common are listed below: Acenaphthene Dibenzo(a,h)anthracene Anthracene Fluoranthene Benzo(a)anthracene Fluorene Benzo(a)pyrene Indo(1,2,3-cd)pyrene Benzo(b)fluorantheneNaphthalene Benzo(k)fluoranthenePhenanthrene Chrysene Pyrene HOW CAN
