A New Threat to Great Lakes Restoration and Our Health

A New Threat to Great Lakes Restoration and Our Health

It’s been refreshing to hear positive news about restoring the Great Lakes these last several years. A much needed source of federal funds—

the Great Lakes Restoration Initiative, which began in 2010—provided a much needed boost to long-term regional cleanup and protection efforts in the U.S. The initiative helped to speed up “toxic hotspot” cleanups, restore critical habitat, tackle the problem of invasive species, and improve water quality. These large strides forward, however, still leave other concerns such as a new and serious problem threatening the health of the Great Lakes, and in particular, its smallest human inhabitants—young children.

Scientists have identified a common product in everyday use—coal tar sealcoats used to repair and protect pavements such as parking lots and driveways—and shown relationships to impaired water quality, a threat to aquatic life, and an alarming health risk to the public, especially young children.

Scientific studies by the U.S. Geological Survey and Baylor University have shown that the coal tar sealcoats are responsible for increasing levels of polycyclic aromatic hydrocarbons (PAHs) found in the sediments of lakes and streams near coal tar sealcoat-treated pavements, and in particles and dust from the pavements. PAHs are a group of chemicals that are formed during the incomplete burning of coal, oil and gas, garbage, or other organic substances like tobacco or grilled meats. PAHs remain in the environment for a long time and a number are suspected or known carcinogens.
Want to know if pavement near you is sealed safely? Tom Ennis of Coal Tar Free America developed a test to find out. By combining mineral spirits and a scraping of dust from the surface of the pavements in a mason jar (don’t forget proper protective wear!) and letting it sit for at least 10 minutes. If the color of the liquid is translucent and clear, it is likely sealed with a coal tar sealcoat. If it is dark and thick, it is most likely sealed with an asphalt product. 

High levels of PAHs run off of coal tar sealcoat treated pavements for months following the application of the product. Routine wear and tear also causes small particles of the pavement (contaminated with PAHs) to run off and end up in nearby waterways harming aquatic life and increasing sediment cleanup costs. People, especially young children, who live by the treated pavements, can breathe in or accidentally ingest the dust and small particles contaminated with PAHs.

The PAHs from the coal tar sealcoats pose a high risk to human health, according to recent scientific studies. People who live adjacent to coal tar sealed pavement for their entire life have a 38 times higher cancer risk than those who live in a typical urban setting without coal tar sealcoat protected pavements.The risk to children is even higher—children who live their first six years by this type of pavement have a 25 times higher risk of getting cancer.

The news is not all bad, however. There is a safer alternative—asphalt sealcoat—which contains about a thousand times fewer of PAHs than coal tar sealcoats.

Freshwater Future is launching a new project aimed at reducing the use of coal tar sealcoats in the Great Lakes. As part of the project, we will be reaching out to communities, universities, suppliers and contractors to obtain their commitment to reduce or eliminate the use of coal tar sealcoats. “It’s astounding that this one product causes many risks and has slipped through the crack of regulation,” notes our Cheryl Kallio.“There are quick and easy things groups can do to join in these efforts.” The benefits are most definitely worth it—a cleaner and safer Great Lakes and healthier people, especially young children. Plus, we will help continue a positive trajectory of restoring the Great Lakes.

To learn more about coal tar sealcoats, the problems they cause and how you can team up with Freshwater Future to help phase out and end the use of the product in our region, contact Cheryl Kallio at Cheryl@freshwaterfuture.org.

1. http://www.usgs.gov/blogs/features/usgs_top_story/youre-standing-on-it-health-risksof-coal-tar-pavement-sealcoat/(accessed June 5, 2014)

2. Williams, E.S., Mahler, B.J., and Van Metre, P.C. 2013. Cancer risk from incidental ingestion exposures to PAHs associated with coal-tar-sealed pavement. Environ. Sci. Technol. 2012, 47 (2):1101-1109.



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Images courtesy of Steven Huyser-Honig,
West Grand Boulevard Collaborative, & Yellow Dog Watershed Preserve.