By Robert McClure 2/17/2012
When you think of pollution, you might picture an industrial center like Camden, N.J., or Jersey City. But new research shows that when it comes to a potent class of cancer-causing toxic chemicals, many American parking lots are a lot worse.
New studies paint an increasingly alarming picture – particularly for young children – about how these chemicals are being spread across big swaths of American cities and suburbs by what may seem an unlikely source – a type of asphalt sealer. These sealants are derived from an industrial waste, coal tar.
Four new studies (links are at the end of this article) announced this week further implicate coal tar-based asphalt sealants as likely health risks. The creosote-like material typically is sprayed onto parking lots and driveways in an effort to preserve the asphalt. It also gives the pavement a dark black coloring that many people find attractive.
Coal tar sealants are used most heavily in the eastern United States, but were applied in all 50 states until Washington state banned the products last year. More than a dozen local governments, including Washington, D.C., and Austin, Texas, also have banned the coal tar sealants in favor of the other major type of sealant, which is asphalt-based.
Asphalt-based sealants contain about 1/1000th the concentration of the cancer-causing chemicals that coal tar-based products do. Home Depot and Lowe’s stores have dropped the coal tar sealants from their product lines, but still some 85 million gallons of the coal tar-based sealants are applied annually in the United States.