Coal-tar pavement sealants might substantially increase children's PAH exposures

E. Spencer Williams; Barbara Mahler; Peter C. Van Metre

doi:10.1016/j.envpol.2012.01.010

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Coal-tar pavement sealants might substantially increase children's PAH exposures

E. Spencer Williams·Barbara Mahler·Peter C. Van Metre

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Abstract

Dietary ingestion has been identified repeatedly as the primary route of human exposure to polycyclic aromatic hydrocarbons (PAHs), seven of which are classified as probable human carcinogens (B2 PAHs) by the U.S. EPA. Humans are exposed to PAHs through ingestion of cooked and uncooked foods, incidental ingestion of soil and dust, inhalation of ambient air, and absorption through skin. Although PAH sources are ubiquitous in the environment, one recently identified PAH source stands out: Coal-tar-based pavement sealant—a product applied to many parking lots, driveways, and even playgrounds primarily in the central, southern, and eastern U.S.—has PAH concentrations 100–1000 times greater than most other PAH sources. It was reported recently that PAH concentrations in house dust in residences adjacent to parking lots with coal-tar-based sealant were 25 times higher than in residences adjacent to unsealed asphalt parking lots.

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E. Spencer Williams, Barbara Mahler, Peter C. Van Metre. 2012. Coal-tar pavement sealants might substantially increase children's PAH exposures. https://doi.org/10.1016/j.envpol.2012.01.010

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