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What are Sealcoat, PAHs, and Coal How does Sealcoat get from Driveways Tar? and Parking Lots into Streams and Lakes, Homes, and the Air? Pavement sealcoat(also called sealant) is a black liquid that is sprayed or painted on some Friction from vehicle tires abrades pavement asphalt pavement. It is marketed as protecting sealcoat into small particles. These particles are and beautifying the underlying pavement, and is used commercially and by homeowners across washed off pavement by rain and carried down storm the Nation. It is applied to parking lots associated drains and into streams. Other sealcoat particles with commercial businesses, apartment and adhere to vehicle tires and are transported to other condominium complexes, churches, schools, and surfaces,blown offsite by wind, or tracked indoors business parks,to residential driveways, and even on the soles of shoes. Some of the PAHs in sealcoat to some playgrounds. Most sealcoat products have volatilize (evaporate), which is why sealed parking a coal-tar-pitch or asphalt(oil)base. Coal-tar-based lots and driveways frequently give off a"mothball" sealcoat is commonly used in the central, southern, smell. Sealcoat wear is visible in high traffic areas and eastern United States, and asphalt-based sealcoat is commonly used in the western United within a few months after application, and sealcoat States. manufacturers recommend reapplication every 2 to PAHs are a group of chemical compounds that 4 years. form whenever anything with a carbon base is burned,from wood and gasoline to cigarettes and meat.PAHs also are in objects and materials, such as automobile tires and coal tar, the production -- of which involves the heating of carbon-based materials. PAHs are of environmental concern because several are toxic,carcinogenic, mutagenc, and/or teratogenic (causing birth defects)to aquatic life, and seven are probable human carcinogens ? (U.S. Environmental Protection Agency, 2009). Coal tar is a byproduct of the coking of coal for the steel industry and coal-tar pitch is the residue remaining after the distillation of coal tar. Coal-tar y pitch is 50 percent or more PAHs by weight and `} is known to cause cancer in humans (International Agency for Research on Cancer, 1980). Coal- tar-based sealcoat products typically are 20 to 35 percent coal-tar pitch. Product analyses indicate Runoff from sealcoated pavement(black surface)enters storm that coal-tar-based sealcoat products contain about drains that lead to local streams.Drain grate(inset)is marked 1,000 times more PAHs than sealcoat products with "DUMP NO WASTE"and"DRAINS TO WATERWAYS." an asphalt base (City of Austin, 2005). tog Gray asphalt pavement shows through where sealcoat has worn off the driveway of an apartment complex.