Research conducted at the UNH Stormwater Center has found that coal-tar-based pavement sealcoat, a type of pavement sealcoat common on driveways and parking lots throughout the nation, has significant health and ecosystem implications.  The research is reported in a feature article in the latest issue of the journal Environmental Science & Technology co-authored by Alison Watts, research assistant professor of civil engineering at UNH. 

Dr. Watts points out that, unlike many complex environmental issues, however, this one has a relatively painless fix: avoid coal-tar-based sealcoats in favor of asphalt-based ones, or no sealcoat at all.

“Consumers generally can’t tell the difference,” Watts says. And voluntary shifts in the market are making that choice easier, she says, noting that retailers Home Depot and Lowes no longer sell coal-tar-based sealcoat, and several commercial sealcoaters use only asphalt-based sealcoat.

“The crux of this issue is that it’s a fairly simply choice we can make that will be beneficial to the environment and to human health without significant impact to the users,” Watts says.

Full article

Journal article: Coal-Tar-Based Pavement Sealcoat and PAHs: Implications for the Environment, Human Health, and Stormwater Management
Barbara J. Mahler, Peter C. Van Metre, Judy L. Crane, Alison W. Watts, Mateo Scoggins, and E. Spencer Williams
Environ. Sci. Technol., 2012, 46 (6), pp 3039–3045.  DOI:10.1021/es203699x