Unlike other compounds, PAHs do not break down easily and thus persist in the environment for decades. Even a small amount of PAHs coming off sealcoated parking lots may overwhelm an aquatic ecological system already stressed by other contaminants.
Increased PAH concentrations in waterways could be a human health issue if people are exposed to it regularly. In addition, dust particles coming from a sealcoated driveway could potentially be troublesome for children who play on the sealed surface. Ballestero cautions that it should not be a major source of concern, but nevertheless he and Watts will be investigating PAH levels in dust from sealcoat later this year.
"You don't see people falling over from PAHs in sealcoat, it's not that big of a health issue," Ballestero says. "But it could be a cumulative exposure problem that gets uglier over time."
Ballestero says he has sensed an interest by the sealcoat industry to offer more environmentally friendly, less toxic alternatives in the future. There should be options that allow workers in the industry to continue to make a living, but without causing additional harm to the local ecosystems and human health, he notes.
"There are much bigger environmental problems out there than PAHs from sealcoats, but the bottom line is that it is easily preventable," Watts adds. "All you have to do is not apply it to pavement."
|Contact: Rebecca Zeiber|
University of New Hampshire