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Coal-Tar-Based Pavement Sealcoat, Polycyclic Aromatic Hydrocarbons (PAHs), and Environmental Health

By B.J. Mahler and P.C. Van Metre

Studies by the U.S. Geological Survey (USGS) have identified coal-tar-based sealcoat—the black, viscous liquid sprayed or painted on asphalt pavement such as parking lots—as a major source of polycyclic aromatic hydrocarbon (PAH) contamination in urban areas for large parts of the Nation. Several PAHs are suspected human carcinogens and are toxic to aquatic life.

First posted February 9, 2011 Report PDF (3.24 MB) For additional information contact: Director, Texas Water Science Center U.S. Geological Survey 1505 Ferguson Lane Austin, TX 78754-4501 World Wide Web: http://tx.usgs.gov/ Part or all of this report is presented in Portable Document Format (PDF); the latest version of Adobe Reader or similar software is required to view it. Download the latest version of Adobe Reader, free of charge.

Suggested citation:

Mahler, B.J., and Van Metre, P.C., 2011, Coal-tar-based pavement sealcoat, polycyclic aromatic hydrocarbons (PAHs), and environmental health: U.S. Geological Survey Fact Sheet 2011–3010, 6 p.

Contents

Key Findings

What are Sealcoat, PAHs, and Coal Tar?

How does Sealcoat get from Driveways and Parking Lots into Streams and Lakes, Homes, and the Air?

The East-West Divide—Regional Product Use Translates to Large Differences in PAH Concentrations

“Fingerprinting” Shows that Coal-Tar Sealant is the Largest Source of PAHs to Urban Lakes

From Outside to Inside—Coal-Tar Pavement Sealant Linked to PAHs in House Dust

Our Environment and Us—What are the Concerns?

FAQ

References