The USGS published their research paper about the contribution of coal tar sealants to 40 lakes across the country. Key findings were:
- Coal tar sealants are the dominant source of PAHs in urban lakes.
- On average coal tar sealants represent half of the source of PAHs in these locations.
These findings are also important because of the claim by some that the research done to date is too geographically isolated to apply to the nation as a whole. This study, plus the USGS parking lot dust study, the University of New Hampshire sealant research, and the New York Academy of Sciences work, gives ample evidence for the problem of coal tar containing pavement sealants in much of the United States.
I put together a nifty little Google map that allows you to zoom into the actual location if you are interested in seeing the aerial photos of the locations. The “pins” on the maps are color-coded that shows the relative concentration of the PAHs found. You can see the geographical range where this is a problem. Check it out and let me know what you think.
View 40 Lakes Sampled by USGS for Coal Tar Sealants & PAH in a larger map.
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