OLYMPIA – Legislation to protect salmon populations from a toxic chemical passed the House Thursday.

Senate Bill 5931 would designate all 6PPD containing motor vehicle tires a priority consumer product under the Safer Products for Washington Act, empowering the state Department of Ecology to do a review of tires containing the chemical and develop regulatory action.

6PPD is found in most, if not all, car tires. It has been used for over six decades to make the tires more flexible and slow their degradation. In 2020, research funded by the Environmental Protection Agency showed  6PPD-quinone — created when 6PPD reacts with ozone in the air — is the most common killer chemical for coho salmon. Studies have shown it can kill the salmon after only a few hours of exposure. The chemical makes its way into waterways through roadway runoff and has been found in many Washington rivers, streams, and the Puget Sound.

“6PPD is killing salmon and other aquatic wildlife at a concerning rate,” said Sen. Jesse Salomon (D-Shoreline), who sponsored the bill. “We’re spending billions of dollars to remove culverts, restore habitats, and protect our salmon populations; we need to ensure we aren’t sabotaging our restoration efforts by ignoring this clear threat.”

6PPD is the second most deadly toxin to aquatic creatures ever studied. The Institute for Fisheries Resources and the Pacific Coast Federation of Fisherman’s Associations filed a lawsuit against tiremakers in 2023, alleging manufacturers violated the Endangered Species Act by using a known toxin.

The EPA also responded to a petition submitted by several Native American tribes calling for regulation, writing it is “necessary to initiate” risk management rulemaking under the Toxic Substances Control Act to “address the risk to the environment from 6PPD-

“Salmon have immense cultural, commercial, and economic importance to our tribal communities,” said Sen. Claudia Kauffman (D-Kent), a member of the Land Use & Tribal Affairs Committee and the Senate’s first Indigenous woman. “Tribes have already called on the EPA to address the deadly risk posed by 6PPD. We need to do our part in Washington to protect our salmon populations from this toxin.”

“In partnership with tribes and the USEPA, Washington state is doing groundbreaking research on 6PPD’s impact on salmon, installing stormwater retrofits to reduce its impact and developing safer alternatives to the chemical so we can ultimately end its use,” said Gov. Jay Inslee. “I’m thankful to Sens. Salomon and Kauffman for their leadership on this important issue.”

“The progress we’ve made on salmon restoration has taken a lot of effort and a lot of funding. Now, the ubiquity of 6PPD threatens to undermine that work,” Salomon said. “Tiremakers have agreed to work with us to find a non-toxic alternative. With passage of this bill, we will be able to act quickly when a safe alternative becomes available.”

Having been slightly amended in the House, the bill now returns to the Senate for concurrence.