Human Health, Coal Tar Sealants, & PAHs: the State of the Science

While our understanding continues to develop on coal tar sealants, polycyclic aromatic hydrocarbons (PAHs) and human health, occasionally it is good to pull all of what we know together into a succinct summary.  That is my hope here.

There are a few studies that have been done directly on coal tar sealants and human health, but many others that either increase our understanding of the concentrations, use, mobility, and environmental effects of coal tar pavement sealants or those that demonstrate the human health effects of PAH.  The references are presented below in the following categories:

1. Direct Studies of Human Health and Coal Tar Sealcoat
2. Human Health Studies of the Effects of PAHs
3. Biological and Environmental Impacts of Coal Tar Sealers
4. Coal Tar Sealant Concentrations, Use and Mobility

These references serve to inform us of the reasonableness of actions to curtail the use and exposure to coal tar pavement sealers.

Paint It Black by the USGS Band

Well if you're hoping for a Rolling Stones song here you may be disappointed.  However the United States Geological Survey (USGS) assembled their own "band" of experts to look at air quality and runoff quality of a freshly sealed coal tar parking area.

Industry Quietly Drops Coal Tar Sealant Standard

In a move that may signal a further weakening of the coal tar sealant industry, one of their standards for residential applications recently lapsed. Interesting since one of the sealant industry's lofty claims is that their product has an ASTM standard.  If you're not familiar with the organization, ASTM (American Society for Testing and Materials) develops standards for all kinds of products and materials.

First Known Federal Agency Goes Coal Tar Free

Credit: U.S. Geological Survey; Department of the Interior/USGS; U.S. Geological Survey/photo by P.K. Cascio

According the Bill Fulk, Chief, Design & Construction Section at U.S. Geological Survey (USGS), the USGS has sent out a memorandum to all of its facility managers that coal tar sealants should no longer be used on any of their paved surfaces.  As far as we know, this is the first federal US agency to take this step.

New Report Calls for "Decisive Action" to Address Sealant Residue in the Mighty Mississippi

Decisive action is needed to address PAHs (polycyclic aromatic hydrocarbons) from coal tar pavement sealants and other contaminants of concern in the Mississippi River according to a recently published report. These are part of the problems found in the section of the River running through the Minneapolis metropolitan area by a joint effort by the National Parks Service and the Friends of the Mississippi River.