Driveway Sealant - Environmental Threat

Driveway Sealant May Pose Environmental Threat

01/15/2011 - If a company dumped the black goop behind a factory, it would violate all sorts of environmental laws and face an expensive hazardous-waste cleanup.

But playgrounds, parking lots and driveways in many communities are coated every spring and summer with coal tar, a toxic byproduct of steelmaking that contains high levels of chemicals linked to cancer and other health problems.

Nearly two decades after industry pressured the U.S. Environmental Protection Agency to exempt coal tar-based pavement sealants from anti-pollution laws, a growing number of government and academic studies are questioning the safety of the widely used products. Research shows that the tar steadily wears off and crumbles into contaminated dust that is tracked into houses and washed into lakes.

In Lake in the Hills, a fast-growing McHenry County suburb about 50 miles northwest of Chicago, researchers from the U.S. Geological Survey found that driveway dust was contaminated with extremely high levels of benzo(a)pyrene, one of the most toxic chemicals in coal tar. The amount was 5,300 times higher than the level that triggers an EPA Superfund cleanup at polluted industrial sites.

High levels also were detected in dust collected from parking lots and driveways in Austin, Texas; Detroit; Minneapolis; New Haven, Conn., and suburban Washington, D.C. By contrast, dramatically lower levels were found in Portland, Ore.; Salt Lake City and Seattle, Western cities where pavement sealants tend to be made with asphalt instead of coal tar.

The findings raise new concerns about potential health threats to people and aquatic life that went undetected for years. {continued}