Letter to the Editor

Oct. 1, 2010

Regarding “A Review of PAHs“ in the September 2010 issue, we appreciate the space Stormwater magazine has dedicated to the issue of urban polycyclic aromatic hydrocarbons (PAHs) over the years. For us, and many cities in the US, PAHs are a serious problem with very few viable solutions.

The city of Austin, TX, banned the use of coal-tar-based sealants in 2006, based on data and studies that were published in the peer-reviewed literature. Since then, even more work has been published on the significance of this PAH source, most notably by the US Geological Survey, the New York Academy of Science, and the City of Austin. We recommend that local governments and water-quality practitioners who are considering policy decisions aimed at PAH reduction rely on peer-reviewed published literature and those analyses conducted following the 2005 documentation of coal-tar sealants as an urban PAH source (Mahler et al. 2005). Reliance on older literature and analyses funded by advocacy groups may be misleading, resulting in sole reliance on end-of-pipe solutions as opposed to prevention. 

We believe a ban of coal-tar sealants is a cost-effective solution for a significant source of PAHs in many urban environments. In Austin, we have been extremely pleased with the cooperation of the local pavement sealant industry and compliance with our ban. By the end of 2010, approximately a million pounds of PAHs will have been prevented from entering Austin’s environment since January 2006, when our ban went into effect. 

We look forward to the results of additional work on PAH reduction in the future, based on rigorous study design and analysis. Thank you for your efforts to keep the issue in the forefront.


Nancy L. McClintock

Assistant Director
Watershed Protection Department
City of Austin, TX

Mahler, B. J., P. C. VanMetre, T. B. Bashara, and J. T. Wilson. 2005. “Parking Lot Sealcoat: An Unrecognized Source of Urban Polycyclic Aromatic Hydrocarbons.” Environmental Science and Technology 39:5560–5566.

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