Coal Tar-Based Pavement Sealers

Definitions

The prohibitions on coal tar-based pavement sealers can be found in Environmental Conservation Law (ECL) Section 37-0119(2) (“the Law”).

Under the Law, "coal tar" means a viscous substance obtained by the destructive distillation of coal and containing levels of PAHs in excess of 10,000 mg/kg (or 1%).

"Pavement product" means a material that is for use on an asphalt or concrete surface, including but not limited to sealcoat.

What are PAHs? 

PAHs, or polycyclic aromatic hydrocarbons, are a large group of organic chemicals that each contain two or more fused aromatic rings comprised of carbon and hydrogen. Anthropogenic sources (sources originating from human activity) of these chemicals include the burning of fossil fuels, coal production, tobacco smoke, and other activities. Natural sources, which are often less significant, include volcanoes and forest fires. Some PAHs are used in the production of dyes, plastics, and pesticides while others are used in asphalt and road construction. 

There are hundreds of chemicals that belong to the group “PAHs” and when these chemicals are produced, they generally occur as complex mixtures of several PAHs rather than as individual compounds. Examples of some of the more common PAHs include: 

• Acenaphthene (CAS 83-32-9) 

• Acenaphthylene (CAS 208-96-8) 

• Anthracene (CAS 120-12-7) 

• Benz[a]anthracene (CAS 56-55-3) 

• Benzo[a]pyrene (CAS 50-32-8) 

• Benzo[e]pyrene (CAS 192-97-2) 

• Benzo[b]fluoranthene (CAS 205-99-2) 

• Benzo[g,h,i]perylene (CAS 191-24-2) 

• Benzo[j]fluoranthene (CAS 205-82-3) 

• Benzo[k]fluoranthene (CAS 207-08-9) 

• Chrysene (CAS 218-01-9) 

• Dibenz[a,h]anthracene (CAS 53-70-3) 

• Fluoranthene (CAS 206-44-0) 

• Fluorene (CAS 86-73-7) 

• Indeno[1,2,3-c,d]pyrene (CAS 193-39-5) 

• Naphthalene (CAS 91-20-3) 

• Phenanthrene (CAS 85-01-8) 

• Pyrene (CAS 129-00-0) 

Why are PAHs Considered Harmful? 

Coal tar-based pavement sealers contain benzo[a]pyrene and other PAHs that have been identified as carcinogens by the US Department of Health and Human Services National Toxicology Program and other government entities. Some of these chemicals are also classified by the European Chemicals Agency as Substances of Very High Concern (SVHC) due to their potential reproductive toxicity, aquatic toxicity, and mutagenicity; however, the health effects of these chemicals all depend on duration and route of exposure, the concentration of PAHs one is exposed to, and the relative toxicity of the PAHs one is exposed to. 

It’s important to note that not all PAHs are the same, meaning the toxicities and associated effects of these chemicals can differ slightly from one PAH to another. Further, both the concentration and exact mixture of PAHs contained in the product can differ across different types of pavement products:

A study conducted by the United States Geological Survey (USGS) in Austin, Texas demonstrated the difference in the concentration of PAHs washed off parking surfaces with different pavement sealants. Parking surfaces sealed with coal-tar based sealcoats (Figure 1, House C) had PAH concentrations approximately 65 times higher than unsealed parking surfaces (Figure 1, House A). Further, parking surfaces sealed with asphalt-based sealcoats (Figure 1, House B) had PAH concentrations approximately 10 times higher than unsealed parking surfaces (Figure 1, House A).

If large concentrations of PAHs are leaching from parking surfaces, they may enter our waterbodies through runoff and/or leach into soils where they have the potential to harm the environment. Research shows that coal tar-based pavement sealers are major contributors to increased concentrations of PAHs in the environment. Once in the environment, they can persist and potentially pose a threat to both humans and wildlife. For example, studies have found that aquatic organisms exposed to high levels of PAHs suffer from stunted growth, liver problems, and other negative impacts. Additionally, PAHs have also demonstrated the ability to accumulate in marine organisms which can ultimately cause further health risks to humans. 

When coal tar-based pavement sealers are used on driveways, PAHs can be tracked into people's homes, posing a threat to our indoor environments as well (Figure 2).  As a result, PAHs associated with coal tar-based sealants have been identified in house dust at elevated levels. As shown in Figure 2, greater concentrations of PAHs on a parking surface can lead to a greater concentrations of PAHs in the home. Someone entering House C after walking on that parking surface (Figure 2, House C) will carry in higher levels of PAHs than someone entering House A after walking on that parking surface (Figure 2, House A). This can become especially problematic when young children, who exhibit increased hand-in-mouth activity, are present in the home. 

The enactment of this law takes important steps to ensure that New Yorkers have access to clean water and safer indoor and outdoor environments. 

Alternative Products

Pavement sealers containing coal tar have been used for decades top seal driveways and parking areas, however, given the concerns with coal tar described above, they are now restricted in New York. An alternative to coal tar-based pavement sealant is asphalt-based pavement sealants, that contain PAHs in substantially lower concentrations (typically 50 ppm total PAH) are on the market and readily available. Alternative or "green" sealants contain 1,000 times less PAH than coal-tar sealants.

Additionally, if you are considering installing or replacing a driveway or parking area, there are safer and more environmentally friendly pavement options such as pervious concrete, permeable asphalt and paver systems which do not require sealants.

Tips for Buying Products or Hiring a Contractor

When hiring a professional to seal your driveway:

• The contractor should know whether their product is coal-tar or asphalt based. Be sure to ask.
• If your contractor does not know, or you would like to verify their answer, request the safety data sheet for their product. If it references chemical abstract service (CAS) numbers 65996-93-2, 65996-89-6 or 8007-45-2, the sealant contains coal tar and its use is prohibited under New York State law.
• If "coal tar," "refined coal tar," "coal tar pitch volatiles," "RT-12," "tar" or similar terms appear in the data, the sealant contains coal tar and its use is prohibited under New York State law.
   

When sealing the driveway yourself:

• Carefully read the label on the sealant. If it references any of the CAS numbers above, the sealant contains coal tar and its sale is prohibited under New York State law.
• If the label references any of the terms above, the sealant contains coal tar and its sale is prohibited under New York State law.

If you have reason to believe that a sealant that is being sold or offered for sale, or applied to a driveway or parking area in this state contains coal tar, please see the option below regarding reporting coal tra products or applicators: 

Reporting Coal Tar Products or Applicators

If you observed a pavement product containing coal tar being sold or offered for sale in New York State or witnessed a pavement product applicator applying pavement products containing coal tar, you can file a complaint in one of three ways.

• Filling out the electronic form
• Fill out a PDF version of the complaint form and submit it to: [email protected]
• Call 518-402-8706 with details of the complaint

Managing Wastes

If you have previously purchased a coal tar-based pavement product to seal your driveway and have not used it, please contact your county, town, or local government which may offer services for receipt of this waste at HHW collection facilities or events. More details on HHW are available on DEC's website.

If you are a small business owner that has purchased a coal-tar based pavement product and have not used it, please see the following guide for information on managing hazardous wastes: Guide: Managing Your Hazardous Waste in New York State (ny.gov) (PDF)