Coal Tar Restrictions: Is Coal Tar Banned in Your City?

Destructive distillation of coal produces two by-products. First is coke, a dark, porous, and brittle substance that resembles coal. 

The second by-product is a liquid called coal tar. It is thick and sticky and has a consistency similar to paint. It also has a glossy brown-black color.

When coal tar undergoes distillation, the result is a product called coal tar pitch. This substance has long been used as an asphalt sealer as it dries into a hard film. It doesn't chip or fade easily, and dries into a nice dark color many property owners love.

The problem is coal tar has been found to contain different carcinogens, including polycyclic aromatic hydrocarbons (PAHs), naphthalene, and benzene. 

One-off exposure to coal tar pitch doesn't result in cancer. But people frequently exposed to coal tar and coal-tar pitch (such as sealcoaters and roofers) have a much higher risk of developing cancer compared to people who are not frequently exposed to this product.

Carcinogens from coal tar and coal tar pitch can also contaminate bodies of water and have been proven toxic to aquatic life. PAHs and dust from coal tar sealer can also cause poor air quality.

That is why several states, counties, and municipalities decided to prohibit the use of coal tar emulsion as asphalt sealer. 

If you live in or operate a sealcoating business in any of these areas, you will need to use Asphalt Emulsion Sealer rather than Coal Tar Sealer, due to local restrictions.