In July of 2016, the City, with support from numerous community groups, banned the use of coal tar sealants or high PAH sealants. This ordinance prohibits the use and sale of pavement sealant products containing >0.1% Polycyclic Aromatic Hydrocarbons (PAHs) by weight, including coal tar-based sealer, in the City of Ann Arbor. The ordinance was passed to help protect, restore, and preserve water quality and the health of residents.
All applicants who apply pavement sealant within Ann Arbor must be registered with the city.
What is coal tar sealant?
Coal tar-based sealant is applied widely on driveways, parking lots, and even play-grounds as a maintenance practice. Coal tar sealcoats are hazardous. They are high in polycyclic aromatic hydrocarbons, or PAHs, many of which have been identified as toxic, mutagenic, teratogenic (cause birth defects) and/or carcinogenic (cause cancer). While there are many sources of PAHs, coal tar sealcoat contains significantly higher concentrations (~70,000 mg/kg) than other common sources such as gas emissions (370 mg/kg) and road dust (24 mg/kg).
Does coal tar sealant present a health hazard?
For someone who spends their lifetime living adjacent to coal tar seal-coated pavement, the average excess cancer risk is estimated to be 38 times higher than for those who don't. Much of the increased risk occurs during early childhood. Children play on and near these surfaces and are, therefore, more likely to inhale or ingest PAHs associated with coal tar sealcoat. Particles also make it into homes on shoes and pets.
Does coal tar sealant impact our water?
In rivers and lakes, PAHs are found primarily in the sediments. Several recent studies have found that runoff from coal-tar-treated surfaces causes death, developmental issues, and other adverse effects in fish and other aquatic organisms long after application.
How can I avoid using coal tar sealants?
Look at product labels or request the Material Safety Data Sheet and avoid products labeled with any of these terms:
CAS#65996-92-1, CAS#65996-93-2 , CAS#65996-89-6, CAS#8007-45-2, Coal Tar, Coal Tar Pitch, Coal Tar Distillates, RT-12
CAS#64742-90-1, CAS#69013-21-4, Steam-cracked Petroleum Residues, Steam-cracked Asphalt, Pyrolysis oil, Heavy fuel oil (HFO)
Available alternatives
There are several alternatives that have significantly lower, or no, PAH content. Asphalt-based sealcoat has 1/1000th the PAH content of coal tar, and is readily available at similar cost. There are also safer acrylic and latex based options.
For more details, please read the ordinance or other links below.
To report a coal tar issue or to get more information, please send an email to coaltar@a2gov.org.