We previously apportioned sources of PAHs in surficial sediments collected from Lake Michigan in 2011 to traffic (53%), coal power plants (25%), coal-tar pavement sealants (15%), and coke ovens (7%).
Since that time, an understanding has emerged of relations between coal-tar-based pavement sealcoat and PAHs in the environment.
Concentrations in unfiltered stormwater runoff from coal-tar-sealcoated pavement are particularly elevated during the months following sealcoat application.
A recently identified outdoor source of PAHs to the environment (16, 17)—coal-tar-based pavement sealcoat has not been considered in any previous investigations of PAHs in SHD.
Tar and chip pavement was torn from a road in town and rolled into piles, ground scouring was noted in several areas, and a 1965 Chevrolet pickup truck was thrown from one residence and never found.
Concentrations of individual PAHs in house dust collected from apartments in Austin adjacent to pavement with coal-tar-sealcoated parking lots were about 140 times higher than those measured in a study of house dust in California.
Concentrations of PAHs in fine particles (dust) on pavement with coal-tar-based sealcoat are hundreds of times higher than those in dust on concrete pavement or on asphalt pavement that is unsealed or that has asphalt-based sealcoat (Table 1).
In response to recent reports that dust from pavement with coal-tar-based sealcoat contains extremely high concentrations of PAH, we measured PAH in SHD from 23 apartments and in dust from their associated parking lots, one-half of which had coal-tar-based sealcoat (CT).
Williams et al. [ 45] also conducted a sensitivity analysis on the Cs and IR (dust and soil) variables, and found that, for adults, the Cs parameter had the greatest influence on assessments that examined exposures to PAHs in soil or house dust adjacent to pavement where coal-tar containing products were not used.
PAHs from pavement sealed with coal-tar-based sealcoat can contaminate the indoor environment as well as the outdoor environment.
