Monday, November 24, 2008

Pavement sealcoat linked to urban lake contamination

From the USGS: Dust collected from coal-tar sealcoated parking lots in Central and Eastern U.S. cities contains concentrations of polycyclic aromatic hydrocarbons (PAHs) that are about 1,000 times greater than levels found in Western cities where coal-tar sealcoat is less commonly used, according to a U.S. Geological Survey (USGS) study published this week in the journal Environmental Science and Technology.

The new study also shows that coal-tar sealcoat - the shiny black material applied to many parking lots and driveways - is contributing to PAH contamination in many of the nation's urban lakes. PAHs are an environmental concern because they are toxic to aquatic life and several are suspected carcinogens.