"A black sealant sprayed on parking lots, driveways and playgrounds turns out to be the largest contributor to the rise of a toxic pollutant in urban lakes and reservoirs across America, according to a new U.S. Geological Survey study.
Scientists saw concentrations of polycyclic aromatic hydrocarbons (PAHs) going up rapidly in the 1990s in areas of urban sprawl. PAHs have been known as a probable human carcinogen since the 19th century, when cancer struck chimney sweeps, said Peter Van Metre, a USGS scientist and a principal author of the report. PAHs also are toxic to fish and other aquatic plant and animal life.
The research was based on sampling of sediments from the bottom of 40 lakes and reservoirs in commercial and residential areas in cities and suburbs typical of where most Americans live — not near old industrial sites. Among the cities tested were Anchorage, Alaska; Fort Worth, Texas; Portland, Ore.; Seattle; Orlando, Fla.; Raleigh, N.C., Chicago, Newark, N.J., Detroit; Milwaukee and Boston."
The late SEJ founding board member Kevin Carmody was one of the first to explore the sealcoat issue in a series of stories about urban water pollution in the Austin American-Statesman in 2003-4.