Clean Wisconsin partners with local groups to tackle toxic coal-tar pavement sealants

, By Ezra Meyer

Clean Wisconsin has built another coalition of environmental organizations, this time in northeastern Wisconsin, to work on the local level to tackle the issue of high levels of toxic PAHs in our communities and in our lakes and rivers.

Driveway and parking lot sealants made with coal tar, a toxic byproduct of the steel-making process, contain extremely high levels of a group of chemical compounds called polycyclic aromatic hydrocarbons, or PAHs for short. PAHs can cause cancer and developmental problems in children and pollute our rivers, lakes, and Lake Michigan, harming fish and other aquatic wildlife.

Research done by the United State Geological Survey and by Clean Wisconsin shows that in Wisconsin urban areas, coal tar-based pavement sealants are the principal source of PAHs that end up in our waters, homes and other buildings.

The good news is that alternative pavement sealant products are readily available on the retail market and they are cost competitive with the coal tar-based products while containing hundreds or thousands of times less PAHs.

We have worked hard to build on our successful work in 2017 and 2018 with partners including Sweet Water, Milwaukee Riverkeeper, and the Milwaukee Metropolitan Sewerage District to educate local communities in Southeastern Wisconsin on this issue. That effort led 13 communities in the Milwaukee area to take local action to curb the use of high-PAH pavement sealants by property owners and contractors.

In 2019, we worked with our partners at the Lakeshore Natural Resource Partnership, the Fox-Wolf Watershed Alliance, and others along the Lake Michigan coast from Sheboygan up to Door County and back down through Green Bay and the Fox Valley to Appleton. We continued to educate members of the public and staff and elected officials at local municipalities about PAHs, the human health and environmental threats they pose, how coal tar-based pavement sealant products are the major culprit putting PAHs into the environment, and what can be done about it at the household, business, and local government levels to reduce those risks.

In February 2019, the City of Sheboygan passed an ordinance, making them the 14th municipality in the state, and the first in Northeastern Wisconsin, to ban coal-tar sealant products.

We will also be taking this work to the Lake Superior coastline this winter and spring, as well as working with more communities along Lake Michigan in Southeastern Wisconsin. This work around the coastal portion of the state is funded thanks to Wisconsin’s Coastal Management Program and the National Oceanic and Atmospheric Administration, as well as by a grant from Freshwater Future.

The good news on this worrisome issue is this: studies in areas that took a proactive approach to this issue and passed coal-tar sealant bans have shown a significant reduction in PAH pollution, so we know these local protections work.

That’s why we’re so excited to work with so many local Wisconsin communities who have taken action, or are are now considering taking action, to ban these harmful products. Many local elected officials have expressed to us a strong interest in taking these important, common-sense steps to protect ourselves and our environment from this easily controlled pollutant.

For more information on coal-tar sealants, please visit

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