Reflections on the Nationwide Effort to Address Toxic 6PPD-q
By: Sean Dixon, Executive Director of Puget Soundkeeper
6PPD-quinone (or 6PPD-q) is on the radar of just about everyone in the environmental space right now, and for good reason. It’s extremely toxic to coho salmon (causing mortality even with very, very low amounts of pollution) and negatively affects coastal cutthroat trout, rainbow trout, and other salmonids. This is alarming to say the least, and the need for solutions isn’t something we can just keep pushing down the road.
6PPD is a chemical used in all tires to prevent them from wearing down too quickly. However, when this chemical sheds from our tires as tire dust on the roads, it transforms into 6PPD-q and is released into the environment. When it rains, this toxic chemical gets carried right into nearby waterways, including the streams that salmon return to each year to spawn.
The fact that 6PPD was first identified in Washington State and is now part of a national conversation says a lot about both the severity of the problem and the strong leadership pushing it forward.
Recently, I attended a roundtable on 6PPD organized by Congresswoman Marilyn Strickland, where tribal voices, researchers, industry representatives, and state agency staff came together to move faster toward solutions to this crisis. One solution, among other strategies, being the phase-out of 6PPD in tires so that it cannot turn into 6PPD-q.
The fact that 6PPD-q was first identified in Washington State and is now part of a national conversation says a lot about both the severity of the problem and the strong leadership pushing it forward.
Panelists included Ed Johnstone, Quinault, representing the Northwest Indian Fisheries Commission, David Troutt from the Nisqually Indian Tribe, scientists from Washington State University and the University of Washington who are leaders in the field of 6PPD-q and salmon mortality research, and representatives from the tire manufacturing and chemical industries. Also in attendance were leaders from Toxic Free Futures, Puget Sound Partnership, Trout Unlimited, Seattle Public Utilities, and other organizations committed to addressing this issue.
Overall, it was clear that the desire to move research forward and the will to find solutions was shared among all panelists and attendees.
After reflecting on the conversations and insights from the convening, I offer what I believe are the critical elements necessary to effectively address the impacts of toxic 6PPD-q:
- Centering Tribal leadership. Across all conversations, tribal consultation and leadership must be foundational, not supplemental. The most compelling and urgent insights came from tribal voices, and future efforts must ensure they guide decision-making and inform action.
- Setting a clear timeline for the end of 6PPD use in tire manufacturing. Health and environmental safety are widely agreed priorities AND progress cannot remain open-ended. Both statements can be true at the same time. Without a defined timeline, there is a risk of indefinite delay while industry works at its own pace. A clear deadline for the removal of 6PPD from tires would both provide accountability and ensure momentum matches the urgency of the need.
- Broadening the geographic and ecological scope. Much of the conversation has focused on Western Washington and coho salmon; this is critical, but not complete. Work by partners such as Spokane Riverkeeper demonstrate the impacts of 6PPD-q in Eastern Washington and statewide. Research studying the effects of 6PPD-q on species like rainbow trout highlight the importance of funding and sustaining the expanding body of research. Future discussions should reflect the full geographic and ecological reach of this contaminant, including urban and rural waterways alike. And, importantly, this broadening will pull more stakeholders into the movement and help build even more momentum for change.
- Folding 6PPD-q solutions into our larger stormwater challenge. Finally, 6PPD-q underscores a broader issue: polluted stormwater runoff remains one of the largest sources of water pollution. As such, environmental advocates must be included early in conversations that shape both immediate mitigation strategies and long-term solutions. For example, investments in green infrastructure offer multiple co-benefits (one of which being the retention of stormwater runoff containing toxic 6PPD-q) and can be deployed now in targeted areas while longer-term regulatory solutions, including a potential ban timeline, are developed.
Puget Soundkeeper is grateful to Congresswoman Marilyn Strickland and her team for including us in this conversation. Though perspectives and approaches vary among a very broad base of stakeholders, one thing is certain: Washington State is, and will continue to be, at the forefront of driving local, statewide, and national solutions to toxic 6PPD-q.