Maybe you’ve seen the headlines across the country discussing the problems with coal tar pavement sealer. This video demonstrates an easy way to see if skin-based exposure to these chemicals is really happening. Other well-known routes of exposure are inhalation and ingestion.

All over North America playgrounds still use coal tar sealers. It exposes children to high levels of chemicals called polycyclic aromatic hydrocarbons or PAHs. Coal tar sealcoats have the highest concentration of any common urban source.

These levels prompted one researcher to say:

“The increased cancer risk associated with coal-tar-sealed asphalt likely affects a large number of people in the U.S.,” says study author E. Spencer Williams, PhD, assistant research scientist at Baylor University’s Center for Reservoir and Aquatic Systems Research.

This video was made to demonstrate the immediate effects of exposure to these chemicals. I learned this trick from an old timer who had worked with these chemicals at a hazardous waste facility. At the end of each day the workers were tested for exposure.

This technique has been documented in several technical resources.

And more recently this method was used to detect exposure to these same chemicals from the BP Oil Spill in the Gulf of Mexico. In 2006 the City of Austin used black lights to detect coal tar sealers. I was surprised to see how easily it showed contaminated skin and lab surfaces.

This video shows how this same approach can detect exposure to coal tar pavement sealers.