"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."--US Geological Survey
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"PAHs are an environmental health issue because several are probable human carcinogens and they are toxic to fish and other aquatic life."
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"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."
Here are my questions: