USGS Release: Contaminated House Dust Linked to Parking Lots with Coal Tar Sealant (1/12/2010 1:38:37 PM)

Hmm! Some of the black tar gunk that's used for sealing cracks in pavement turns out to be made from coal dust byproduct too. It also potentially contains carcinogenic particles:

"Coal-tar-based sealcoat—the black, shiny substance sprayed or painted on many parking lots, driveways, and playgrounds—has been linked to elevated concentrations of the contaminants polycyclic aromatic hydrocarbons (PAHs) in house dust."
...
"PAHs are an environmental health issue because several are probable human carcinogens and they are toxic to fish and other aquatic life."
...
"Two kinds of sealcoat products are widely used: coal-tar-emulsion based products and asphalt-emulsion based products. National use numbers are not available; however, previous research suggests that asphalt-based sealcoat is more commonly used on the West Coast, and coal-tar based sealcoat is more commonly used in the Midwest, the South, and on the East Coast."

--US Geological Survey
Here are my questions:


1) Which sealcoat does UM-Dearborn use?

If it is one of sufficient concern, then
2) What quantifies a PAH concentration significant enough for fish and other aquatic life?
3) How much carcinogenic PAH does one find in every day places like the air, water, and soil on campus in comparison to the parking lots?

Given UM-Dearborn's high traffic and close proximity to the Rouge River (which runs through campus), I wonder what alternatives are available to use in its stead.

Link to today's full USGS media release:
USGS Release: Contaminated House Dust Linked to Parking Lots with Coal Tar Sealant (1/12/2010 1:38:37 PM)