Can Your Driveway Make You Sick?


I’m Putting WHAT on My Driveway?

The black shiny top coat you put on your driveway to protect it from weathering and to maintain a dark, glossy appearance could be coal tar-based or contain other components with high levels of polycyclic aromatic hydrocarbons (PAH).

A Known Carcinogen

Coal tar sealants and certain other sealants are a potent source of PAHs, a fact well-documented by the U.S. Geological Survey (USGS) and other researchers. Coal tar and some PAHs are recognized carcinogens by the U.S. Department of Health and Human Services and international agencies.

PAHs are Dangerous

In humans, prolonged exposure to PAHs has been linked to cancers, and PAHs can cross the placental barrier in pregnant women. Sealant particles containing PAHs in rivers and streams can inhibit reproduction and cause DNA damage, mutations, cancer and death in aquatic life forms.

Why Does It Matter?

Sealants do not stay on your driveway.  Sealant particles degrade in sunlight, and flake off with vehicle and foot traffic as well as snow removal.  Particles can blow onto soil and wash into ponds and streams with stormwater.  The particles are tracked into homes by people and pets, where potentially carcinogenic dust and PAHs can be inhaled, ingested and absorbed through the skin.

Studies have shown that dust in homes by parking lots with coal tar-based sealants have PAH concentrations 25 times higher than homes next to parking lots without coal tar sealants. Models suggest that over a lifetime the risk for cancer can be 38 times higher for people living adjacent to coal tar sealed pavements. Exposure for children under six years of age carries the greatest risk.

Better Alternatives

Safer asphalt-emulsion sealants have about 1/1,000th the PAHs of coal tar sealants. Asphalt-emulsion or latex-based sealants are similar in cost and durability to coal tar sealants and are widely available in stores and from contractors. Alternately, residents may choose to leave pavement unsealed or replace asphalt with concrete, pavers or surfaces other than asphalt.

Talk to Your Contractor

When negotiating with a contractor to sealcoat a driveway, tennis court or common subdivision road, specify that you want a latex-based or asphalt-emulsion sealant. Request a safety data sheet for the contractor’s product to confirm. Avoid a sealant with any of the following Chemical Abstract Service (CAS) numbers on its ingredient list:

CAS#’s 65996-92-1       65996-93-2        65996-89-6        800745-2         64742-90-1       69013-21-4

If You Buy and Apply

When shopping for a sealant, look for latex-based or asphalt-emulsion sealants. Most home improvement stores sell these safer sealants. Avoid products with the words:  coal tar, coal tar pitch, refined tar, coal tar volatiles, pyrolysis fuel oil, steam-cracked petroleum residues, RT-12, steam-cracked asphalt, heavy fuel or pyrolysis oil, ethylene tar, ethylene bottoms or related terms and avoid products with the CAS numbers above.

Lastly, talk to your neighbors. Be sure they know the dangers.  Ask for latex-based asphalt-emulsion sealants so our neighborhoods are safer for everyone.

For more information go to

Sealants are applied on driveways, playgrounds, and other asphalt pavements to give old surfaces a black, glossy restored appearance. But if toxic coal tar and other high PAH sealants are used, they come with a potential danger. Coal tar sealants are linked to an increased risk of cancer, especially in children. Look inside for ways to protect yourself and your family.

Ask for latex-based or asphalt-emulsion sealants

The Barrington Area Council of Governments is a voluntary organization of elected officials representing the Villages of Barrington, Barrington Hills, Lake Barrington, North Barrington, South Barrington and Tower Lakes, and Barrington and Cuba Townships.