Washington State is poised to become the first state to ban coal-tar sealant used on pavements and parking lots.
A state measure—overwhelmingly approved last month by the House and now under consideration in the Senate—would ban the toxic asphalt sealant derived from coal tar, a waste product of steelmaking.
Studies have shown that the sealant emits high concentrations of Polycyclic Aromatic Hydrocarbons (PAHs), which have been linked to cancer and the death of exposed fish and aquatic wildlife. Concentrations in coal tar are about 1,000 times higher than levels found in alternative, asphalt-based sealants, according to studies by the U.S. Geological Survey.
US Geological Survey
Coal-tar-based sealcoat products contain
about 1,000 times more Polycyclic Aromatic
Hydrocarbons (PAHs) than sealcoat products
with an asphalt base.
Austin, TX; Washington DC; Madison, WI; and other cities have banned the substance, but Washington would be the first state to do. U.S. Rep. Lloyd Doggett, a Democrat who represents the Austin area, has called for years for a national ban on the sealant.
Sales, Usage Bans
The measure would:
• Ban all sales of coal tar pavement products as of Jan. 1, 2012; and
• Ban the use of coal tar pavement products on driveways and parking areas as of July 1, 2012.
Coal-tar sealants, used primarily by private contractors, are the main cause of rising PAH levels in the sediments of 40 lakes monitored nationwide by the USGS, agency scientist Peter Van Metre told Washington’s Senate Environment, Water and Energy Committee at hearing March 22 on the measure. Van Metre has been studying the issue since the 1990s.
Mo McBroom, policy director of the Washington Environmental Council, told senators that stormwater runoff was likely carrying coal-tar sealant into Puget Sound. “This is a tangible step we can take to reduce stormwater pollution entering our water bodies,” McBroom said.
The state Ecology Department also backs the bill. Toxics coordinator Carol Kraege told legislators that the sealant chemicals accumulate in the food chain: “Our position is these chemicals . . . are the worst of the worst, and the sooner we phase them out, the better.”
The Pavement Coatings Technology Council, a manufacturer’s group based in Alexandria, VA, opposes the measure, saying it would burden small businesses. The council notes that PAHs are also present in vehicle exhaust and power generation, construction materials and consumer products. The council has said it found no change in PAH concentrations two years after Austin banned the sealant.
Council scientist Anne LeHuray asked Washington’s senators to hold off on the bill until the Department of Ecology completes a study of PAH contamination sources.
“It would be premature to pass this bill before the study is complete,” she said, according to The Olympian.
Opponent Rep. Shelly Short, R-Addy, said the bill was unnecessary because many retailers in the region had already stopped selling the product. (Coal-tar-based sealcoat is commonly used in the Central, Southern and Eastern U.S.; asphalt-based sealcoat is more common in the West.)
Short tried unsuccessfully to attach an amendment to the measure that would have required the Department of Ecology to conduct follow-up studies and report to the legislature by Dec. 1, 2015, whether the measure had reduced PAH in stormwater runoff.
In addition to the December 2010 survey that revealed contamination of 40 urban lakes, Van Metre noted a 2009 study in which USGS researchers tracked the chemicals into house dust at apartments adjacent to coal-tar-sealed parking lots at a rate 25 times higher than apartment houses using asphalt-based sealants.
“We’re not talking about old industrial waste sites here,” Van Metre told Washington legislators last week. “We’re talking about suburban neighborhoods.”