Emerging Issue E-Alert:
Media Reports Cancer Risk From Coal Tar
Written By Attorneys: Kim Hollaender and Adam J. Pantano
This article is an interpretation of current law and is offered for informational purposes only. This material is not legal advice and should not be construed or used as a substitute for the advice of an attorney.
Multiple media sources and a January 12, 2010 study by the U.S. Geological Survey ("USGS"), entitled Contaminated House Dust Linked to Parking Lots with Coal Tar Sealant, have recently sounded an alarm, questioning whether chemicals in coal tar sealants cause cancer in humans. However, the USGS's report may be flawed by faulty controls as well as questionable findings and conclusions.
At issue are the levels of polycyclic aromatic hydrocarbons ("PAHs") found in coal tar sealants applied in parking lots in Austin, Texas, as well as the dust that purportedly resulted when the sealant broke down over time. The USGS study suggests that coal tar sealants may have high levels of PAHs relative to other PAH sources like soot, vehicle emissions and used motor oil. Coal tar sealants are very widely used and accepted, although the City of Austin, Dane County, Wisconsin and Washington, D.C. banned its use as early as 2006. Industry sources dispute the USGS study's findings and conclusions as ill-founded.
Coal tar is widely used as a sealant to protect pavements and asphalt surfaces against cracks and water damage. Asphalt-based sealant is more commonly used in western states while coal tar is more common in central and eastern states. The USGS study sampled 23 ground floor apartments in Austin, Texas. Eleven were adjacent to a coal tar sealed parking lot. The remainder abutted parking lots coated with some other substance or not sealed at all. USGS found that the 11 apartments next to coal tar sealed parking lots had concentrations of in-house PAH dust levels that were 25 times higher than units next to parking lots coated with other substances or uncoated. Dust found on coal tar coated parking lots had PAH concentrations that were 530 times higher than dust found on parking lots without coal tar sealcoat.
Many assumptions and conclusions of the USGS study have been heavily criticized by industry sources, suggesting that sloppy science may play a role. In its study, USGS relied on scrapings of the sealant to determine PAHs levels. However, USGS failed to adhere to any established standard set forth by ASTM, EPA, or equivalent body, as a protocol for gathering and handling its study samples. Some experts theorize that the PAH contamination more likely comes other sources, ones that USGS ignored. Waste generated by manufactured gas plants in the Austin area, dumped into quarries, caves or other depressions in the area, may account for the higher PAH levels. One such gas plant is in the Barton Creek area. The USGS study failed to consider the S Mo-Pac Highway as a point source, which is approximately 2000 feet away from Barton Creek. This omission may be critical and a source of faulty findings.
PAH pollution can be caused by more than coal tar sealant. Car exhaust, asphalt wear, tire wear, and engine oil leaks and spills are other usual suspects. Higher PAH levels may simply reflect highway run-off of tire wear, drifting car exhaust or unavoidable oil leaks. Moreover, the USGS study ignored urban sprawl as a more likely explanation for the increased PAH levels in the watershed. The USGS study has not been submitted for peer review by the scientific community, avoiding the scrutiny of the study's evidence, assumptions, findings and conclusions that it appears it deserved.
Where does this leave insurers of manufacturers, distributors, property owners and end-users of coal tar based sealants? The alarm sounded by USGS, regardless of its merits, signals that increasing attention, by the plaintiffs' bar among others, will be paid to allegations that coal tar sealant causes illness. In February 2006, U.S. Rep. Lloyd Doggett, (D.-Texas) asked the EPA to study the dangers of coal tar sealants, and is seeking a nationwide ban of coal tar based pavement sealants. Future federal and state legislative and agency action may be likely. Industry participants and liability insurers are advised to pay close attention to the issue, with particular focus on the growing scientific debate. Sloppy science and unfounded conclusions should not be allowed to frame public perception, and industry participants and liability insurers may wish to provide the public with a more accurate presentation of the facts. NLdH is closely monitoring this issue and will provide updates on noteworthy developments as they occur.
