Carolinas Concrete Parking Lots

Concrete Produces No Toxic Runoff...Study Shows Asphalt Sealcoat Poses Environmental Threat!

According to a recent study in Texas by the U.S. Geological Survey National Water Quality Assesment (NAWQA) program and the City of Austin, the black emulsion sealcoat applied to asphalt pavement has extremely elevated concentrations of polycrylic aromatic hydrocarbons (PAHs) and can significantly affect the quality of downstream water resources.  PAHs are known to have averse health effects on animals, plants and people.  Small particles of sealcoat flake off as they are abraded by vehicle tires and can wash into urban streams with rain and runoff. 

The study found that particles in runoff from coal-tar based sealcoated parking lots have PAH concentrations that are about 65-times higher than in particles washed off parking lots that have not been sealcoated.  Particles in runoff from parking lots sealed with asphalt-based sealcoat, the other major product on the market, have PAH concentrations about 10-times higher than those from unsealed lots.

September 2006 Update:  Two Senators Urge EPA to Study Asphalt Sealant Runoff

Senators Jim Jeffords (I-Vt.) and John Warner (R-Va.) have asked EPA Administrator Stephen Johnson t conduct studies on how sealants commonly used on asphalt pavements increase concentrations of toxic substances (PAHs) in watersheds, and how such contaminants affect human health and the environment.

Studies from the U.S. Geological Survey (USGS) over the past two years have shown that the chemicals can cause cancer in humans and kill aquatic life in high concentrations.  The substance has long been associated with lung cancer among roofers and asphalt workers, according to the National Institute of Environmental Health and Science.  (Based on a report by E&E Daily).