A handful of new studies supports what some in the stormwater industry have maintained for years: coal tar-based pavement sealers pose risks to the environment, and to human health as well.
The city of Austin, TX, pioneered research in this area. This article in the May/June 2006 issue of Stormwater chronicles the detective work the city did to determine why PAH levels in some city creeks were so high. Working with the US Geological Survey, the city eventually tested runoff from a number of parking lots—sealed, unsealed, and concrete—and from test plots coated with different types of sealants. (Asphalt-based sealants don’t pose the same problems.) Austin banned the use of coal tar-based sealants in January 2006.
Several other cities have since banned their use as well, and last year, Washington became the first state to do so.
The concerns early on were mainly about the sealants’ effects on aquatic habitats. However, coal tar is also a human carcinogen. Research now shows that dust from parking lots and driveways coated with these types of sealants contains toxins that show up in nearby homes, and that people are ingesting it as they eat; the amount ingested by very young children—who tend to put all sorts of objects in their mouths—can be more than nine times as much as that ingested by older kids and adults.
The recent studies on the environmental and human health effects of coal tar-based sealants appear in Atmospheric Environment, Chemosphere, Environmental Pollution, and Environmental Science & Technology.
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Upcoming Forester University Webinars
February 23rd, 2012
Stormwater Pond BMP Management: Design, Operation & Maintenance
Stormwater ponds are one of the most common urban rainwater runoff BMPs thanks to their reliability and predictability, but performance is design and maintenance dependent. Join Shahram (Shane) Missaghi of the University of Minnesota to explore stormwater pond design, operation and maintenance presented in an integrated stormwater pond management plan that effectively manages your stormwater and protects the water quality of your natural resources. Read more…
March 8th, 2012
Reducing Water, Energy, and Tax Bills for Facilities
Are you overpaying on your facility’s three largest variable costs: water, energy, and taxes? Join Fraser Allport, CEO, to explore how to reduce your facility’s utility and tax bills and future-proof for sustained performance by combing green technologies (green hardware and smart software) with government tax incentives in a cost-reduction action plan designed to obtain, quantifiable and sustainable resource and cost-savings results. Read more…
March 22nd, 2012
5 Proven Social Media Tactics to Engage Your Audience
Extend your outreach and campaign effectiveness with social media. Join Erica Hooper, Strategic Director at S. Groner Associates, to explore social media's (e.g., Facebook, Twitter, etc.) opportunities, myths, and real-world tested and proven social media tactics designed to engage your audience. Read more…