EPA Takes Step to Protect Salmon from Tire Chemicals

Image: Environmental Protection Agency.

Environmental Protection Agency officials have announced an intention to publish an advanced notice of rulemaking under the Toxic Substances Control Act (TSCA) to gather information that could be used to ban use of a chemical used in tires and found to be lethal to coho salmon.

The decision, announced on Nov. 2 by the U.S. Environmental Protection Agency (EPA), was in conjunction with the EPA’s decision to grant a petition submitted in August by the Yurok Tribe in California and the Port Gamble S’Klallam Tribe, and the Puyallup Tribe of Indians, both of Washington state.

The petition asked the EPA to consider establishing regulations prohibiting the manufacturing, processing, use and distribution of the chemical N-(1,3-Dimethylbutyl)-N’-phenyl-p-phenylenediamine (6PPD) in tires.

The chemical has been used in motor vehicle tires for more than six decades to make them more durable. It can also be found in other rubber products such as footwear, synthetic turf infill and playgrounds.

The issue is that 6PPD reacts with ozone pollution in the air to form a byproduct called 6PPD-quinone, which may be present in stormwater runoff from parking lots and streets due to the presence of tire wear particles. Runoff may be washed into streams and other bodies of water during rain events, resulting in aquatic organisms being exposed to 6PPD-quinone.  As a result, aquatic organisms can be exposed to 6PPD-quinone.

The EPA said that concentrations of 6PPD-quinone in stormwater in the Pacific Northwest were found to be lethal to coho salmon after only a few hours of exposure.

“These salmon and other fish have suffered dramatic decreases in population over the years,” Michal Freedhoff, assistant administrator for the EPA’s Office of Chemical Safety and Pollution Prevention, said. “Addressing 6PPD-quinone in the environment, and the use of its parent, 6PPD, is one way we can work to reverse this trend.”

The EPA said it plans to publish an advanced notice of proposed rulemaking under Section 6 of the TSCA by the fall of 2024 in order to collect information that could be used to inform a subsequent regulatory action.

The agency also said that it plans to finalize a rule under Section 8(d) of TSCA to require manufacturers (including importers) of 6PPD to report lists and copies of unpublished health and safety studies to EPA by the end of 2024.

EPA-funded research first established a link between 6PPD-quinone and salmon deaths in the Puget Sound region in 2020. Since then, EPA has been engaged in ongoing efforts with other federal agencies, states, tribes, industry, and other stakeholders to address information gaps and address concerns regarding the use of 6PPD and the risks of 6PPD-quinone.

EPA continues to fund research activities to expand its understanding of the impacts of 6PPD-quinone, and to fill data gaps.