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Coal Tar Hazards

As coal tar coatings age and abrade from tires, excessive heat, snow plows, and normal oxidation, the toxic chemicals accumulate and make their way into our homes and in our water sources.

What is Coal Tar?

Coal tar sealants, are refined tar emulsions derived from crude coke oven tar produced in the manufacturing of steel. The resulting pitch exhibits a dark sheen and is used to beautify and help protect pavement and asphalt against cracking and water damage. The polycyclic aromatic hydrocarbons (PAHs) in coal tar have a significantly different chemical makeup than asphalt pavement allowing them to adhere to inorganic and organic surfaces alike. They don’t dissolve readily in water and have a high resistance to petroleum products. Coal tar based sealants contain the highest concentration of PAHs—between 20% and 35%—whereas asphalt-based sealants only contain about 5% PAHs. Coal tar has been used in all 50 states and reapplication is recommended every 2-4 years.

​Elevated PAHs found in Coal Tar:
   negatively impacts ecosystems,
   abrades off into water sources,
   concentrates into house dust,
   known to cause cancers.

In the last 10 yrs. coal tar pitch has been cited as a Hazardous Substance by OSHA, ACGIH, DOT, NIOSH, NTP, IARC, and NFPA. Increasing studies have shown coal tar coatings to be highly toxic to animal, plant, and human life. Many cities and counties have created expensive remediation laws and programs to safely remove the toxic substance from pavement surfaces and dispose of it in an environmentally sound manner.

In the News

(Luisa Wiewgorra, FOX 47, 01/31/2022)


“We get our water from the groundwater. So, the more that we can protect it, the better long term we are.”

–Tom Jancek, Grand Ledge City Council

Grand Ledge has banned the use of coal tar-based sealants, following mid-Michigan’s Meridian Township and East Lansing.

"We wanted to do something with the PAHs before it became a problem. And there are solutions now.
You just use a different sealer."

–Tom Jancek, Grand Ledge City Council

“If you've got coal tar on your parking lot, you will have high PAH is in your apartment..that's where our kids play…They're constantly putting stuff in their mouth. And that's what, that's the way they experience their world. Well, they're experiencing it in a pH rich environment. And it's significant enough to increase their lifetime cancer risk 38 times by up for a child in those kinds of circumstances."
--Thomas Ennis, Advocate and Founder of Coal Tar Free America


Katherine Hafner, The Virginian-Pilot, 01/31/2022)


"When I think about what we’ve done over the years for water quality, there’s been a lot of toxic products that we’ve phased out, and we’re better for it. We see it’s harmful and we get rid of them and we look back and don’t regret it.”
–Joe Wood, Senior Scientist, Chesapeake Bay Foundation

Friction from car tires wears the sealant into small particles that can be tracked indoors or washed down storm drains and into waterways.

People who lived next to coal-tar-sealcoated pavement had a 38 times higher risk of developing cancer, according to the U.S. government.

"Asphalt sealants are common alternatives to those made of coal tar. They work just as well and are no more expensive. So why not?”

–Joe Wood, Senior Scientist, Chesapeake Bay Foundation
Meanwhile, the EPA’s Chesapeake Bay Program — a large restoration coalition of nonprofits, governments and academic institutions — has prioritized the coal-tar class of chemicals as among the most critical contaminants to the bay watershed.


(Iris Perez, FOX 9, 1/02/2019)

A lawsuit filed by 7 Minnesota suburbs alleges 7 manufacturers knowingly contributed to the contamination of hundreds, if not thousands, of state stormwater ponds by way of coal tar. 


"Clearing Minnesota ponds of PAHs, will cost millions. This may be a beacon not just around this state, but elsewhere that this is a serious situation.”
-- Attorney Dan Shulman

Below are links to articles and studies pertaining to Coal Tar Hazards.

​Health Risks to Children

"Studies: Children living in homes adjacent to pavement with coal-tar-based sealcoat were likely exposed to about 14-fold higher doses of PAHs than those living adjacent to unsealed pavement. 
Columbia Center for Children’s Health: PAHs in homes can contribute to delays in cognitive development, asthma and other respiratory symptoms, obesity and metabolic disorders, or changes at the molecular level that could increase children’s cancer risk”.

UNH Research, March 14, 2012

"Studies: Health risk to Children from toxic pavement sealant greater than previously believed. Children living by coal tar-sealed parking lots and driveways are getting a bigger dose of PAHs from house dust than from their food.​"

NBC News, February 17, 2012

"Children at Risk for Ingestion of PAHs from Pavement Sealant, Study Finds"
Baylor Media Communications,

Baylor University Media, February 13, 2012

Coal Tar Impacts Our Health

NIOSH Pocket Guide to Chemical Hazards (Coal Tar) 2011

Coal Tars and Coal-Tar Pitches, CAS No. 8007-45-2 Report on Carcinogens, Twelfth Edition (2011), National Toxicology Program, Department of Health and Human Services

EPA Study Finds Coal-tar Sealants Creates Polycyclic Aromatic Hydrocarbons Runoff, January 2016

Coal Tar Concerns at Home

"Is Your Backyard Toxic? Hidden Chemicals make the great outdoors a little less great. Here are three surprising danger zones."

Natalie Gingerich Mackenzie

Readers Digest, July 2012 Issue

"Too Toxic for the Landfill, but OK for your Driveway. U.S. agency’s study finds dangerous levels of chemical are tracked into homes."
Chicago Tribune, January 16, 2011

"Coal-Tar-Based Pavement Sealcoat A Major Source of Polycyclic Aromatic Hydrocarbons (PAH's) in Urban and Suburban Environments"
USGS RESEARCH, February 2011

"Study sees parking lot dust as a cancer risk. Sealant doesn't stay put on pavements...alarming levels of coal tar dust showing up in homes."
MSNBC News, January, 12, 2010

Communities Remove/Ban Coal Tar

Minneapolis Getting Ready To Ban Coal Tar Coatings. Coal-tar sealers...can cause birth defects for aquatic life and cancer in humans according to a presentation by the city’s Regulatory Services staff.
MINNPOST, July 10, 2012

Washington DC District Orders Removal of Toxic Coal Tar Sealant From Private Parking Lot... “It is illegal to sell, use, or permit the use of coal-tar pavement products on your property, subject to a daily fine of $2,500. The District Government issued this ban to protect human health and our environment.”
Coal Tar Ban in The District of Columbia, July 1, 2009

(Washington) State bans coal tar sealants in big win for foes: Toxic ingredients turn up in water, house dust, researchers say..., May 5, 2011

First in The Nation Coal Tar Ban passes, State of WA ...(Coal tar found) responsible for significant stormwater pollution and toxic contamination in lakes and waterways across the country.
Washington Environmental Council, April 13, 2011

Coal Tar Coating Ban - Dane County (Madison) Wisconsin

Coal Tar Coating Ban - Austin Texas
Communities Object to Products Containing Coal Tar

"Neighbors, homeowners association at odds over road improvement project." 
While most homeowners would probably welcome road improvements in their neighborhoods, members of one community are fighting back to stop a road project they say would put their health at risk...Government studies find increased health and environmental risks when spraying "coal-tar-based seal products" on top of the roads.
Connor DelPrete, WECT News, North Carolina, October 30, 2017

Coal Tar Impacts Our Ecosystem

"Parking-Lot Sealcoat: A Major Source of PAHs in Urban and Suburban
Environments" (Study) ...particles in runoff from coal-tar based sealcoated parking lots have PAH concentrations that are about 65 times higher...(and) have been increasing over the past 30-35 years in many urban and suburban lakes across the United States.
National Water-Quality Assessment (NAWQA) Program and the City of Austin, TX
Updated January 9, 2013

"Parking Lot Sealants: On the Trail of Urban PAHs"
Stormwater Magazine,
May/June 2006, reposted February 20, 2012

"PAHs Underfoot: Contaminated Soils From Coal Tar Coatings Dust Widespread in the United States"
USGS Report March 28, 2009

Coal Tar Coatings Unsafe for the Ecosystem, Polycyclic Aromatic Hydrocarbons (PAHs) Fact Sheet
Illinois Department of Public Health, June 2005, revised, February 2009

Coal Tar Seal Coat Linked To Lake Contamination: USGS findings show that dust
eroded from coal-tar treated parking lots in the six Central and Eastern cities had
concentrations of PAHs that were about 80 times higher.
Science News, November 30, 2008

"Would You Kiss These Lips?" Toxic PAH's cause tumors in fish.
Chesapeake Bay Program, February 1, 2007

Austin's Coal tar Ban 10 Years Later, Environmental Commission Briefing, December 2015

Austin's Coal tar Ban 10 Years Later, Slideshow, December 2015

Asphalt Institute Study on "Differences Between Asphalt & Coal Tar"


Paint it Black – USGS Study
Documentary  :  November 2, 2012

Unofficial Guide to the USGS and Coal Tar Sealants
Presentation Video  :  April 10, 2011

Effects of Coal Tar On Stream  in North Carolina (BB&T)
Boone Town Council Presentation  :  September 22, 2010

Effects of Coal Tar On Stream  in North Carolina (BB&T)
Environmental Editorial  :  July 17, 2010


Coal Tar Free America

Most informative website keeping track of this contentious issue.

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