A Summer Maintenance Project That Could Threaten Your Health

Posted on July 9, 2014 by

With the snow gone and summer in full swing, homeowners, schools, businesses and others may be considering sealing their aging driveways, sidewalks, or parking lots. However, scientific studies confirm that coal tar sealcoats, the most common type of sealcoat used on driveways and parking lots in our region, can present a health risk to the public.

Coal tar sealcoats contain polycyclic aromatic hydrocarbons (PAHs), many of which are suspected or known carcinogens.  The routine wear and tear of coal tar sealcoated pavements produces dust and particles contaminated with PAHs that can be breathed and accidentally ingested by people living by the pavements.  One recent study by the U.S. Geological Survey and Baylor University found:

  • For someone who spends their entire lifetime living adjacent to coal tar sealcoated pavement, the average excess lifetime cancer risk is estimated to be 38 times higher than the urban background exposure.
  • More than one-half of the risk occurs during the first 18 years of life.  (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.)

“The U.S. Geological Survey also found that people, especially young children, who live by, play on or around the treated pavements, can breathe in or accidentally ingest the dust and small particles contaminated with these PAHs,” notes Cheryl Kallio, Associate Director with Freshwater Future. “Fortunately, there are alternatives such as asphalt sealcoat emulsions, and as local and state governments are becoming more aware of the threat they are taking steps to protect citizens.”

Recently, the state of Minnesota has banned the use of coal tar sealcoats. There are a variety of additional bans growing throughout the Great Lakes region from Dane County, Wisconsin to the University of Michigan, and statewide legislation proposed in Illinois and New York. Additionally, Home Depot and Lowes have made commitments to not sell coal tar sealcoats throughout the U.S.

To learn more about coal tar sealcoats click here.


© 2021 Freshwater Future. All Rights Reserved.

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