Department of Ecology
Committees, Boards, and Workgroups

This page is run by the Washington State Department of Ecology and serves as a resource hub for those closely following 6PPD. In addition to this page, we include links to other pages that are relevant to 6PPD below. For more general information about 6PPD, please visit our website.

What is 6PPD?

In 2020, researchers at the University of Washington-Tacoma, Washington State University, and additional collaborators identified the connection between car tires, 6PPD-quinone, and pre-spawn mortality in coho salmon. In response to this discovery, Ecology is taking action to protect humans and aquatic organisms from these chemicals, including closely monitoring ongoing research and conducting research of our own. 

Past Events

6PPD Webinar: June 21, 2023 from 1 to 3 p.m. PDT

State agencies, including the Department of Ecology, Department of Fish and Wildlife, Department of Health, Department of Transportation, and Puget Sound Partnership prepared materials to share our ongoing work addressing 6PPD and 6PPD-quinone. We invited participants to review these materials (below) in advance of the event, then submit questions using our online comment form.

During the event, we responded to live questions and questions we received through our comment form. You can read written responses to many of these questions and access resources we shared in our 6PPD interagency webinar follow-up document. 

Informational materials for webinar

• Department of Ecology
  • Recorded presentations:
    • Part 1 - 6PPD and 6PPD-quinone: Identification of a Problem and the Cause (temporarily unavailable; coming soon)
    • Part 2 - 6PPD and 6PPD-quinone: Source Reduction
      • This video contains information about our 6PPD Alternatives Assessment Hazard Criteria, which were available for public comment from June 14, 2023 to July 14, 2023. 
      • You can view the 6PPD Alternatives Assessment Hazard Criteria here. 
      • You can submit input on these criteria using this comment form. *Note: the comment period is now closed.
    • Part 3 - Assessing 6PPD-quinone in the Environment
    • Part 4 - Stormwater Best Management Practices
  • Focus sheets: 
    • Focus on: Best Management Practices for 6PPD-q 
    • Focus on: Reducing Sources of 6PPD 
    • Focus on: Monitoring 6PPDs-q in the environment  
• Department of Health
  • 6PPD and People's Health
• Department of Transportation
  • WSDOT Stormwater Retrofit
  • WSDOT Stormwater Retrofit: 2023/2024 Prioritization Update Survey123
  • WSDOT Move Ahead Washington Funding & Prioritization Opportunities
• Puget Sound Partnership
  • 6PPD Efforts in Puget Sound

Webinar Follow-Up Materials

• 6PPD interagency webinar follow-up document
• Written responses to pre-submitted questions

Understanding the Problem

We are developing methods to test and monitor 6PPD and 6PPD-quinone in the environment so we can identify areas most affected by these chemicals.  

Please visit our Evaluating 6PPD in the Environment page to review technical materials related to this work.

Reducing Sources of 6PPD

Our ultimate goal is to reduce sources of 6PPD-q, which requires finding a safer alternative to 6PPD to use in tires. We will conduct an alternatives assessment to identify possible safer alternatives to replace 6PPD. 

Please visit our Research and Proposed Alternatives to 6PPD page to review technical materials related to this work.

Reducing Stormwater Pollution

Stormwater best management practices can help reduce the amount of 6PPD-q that makes its way into creeks and streams.

Please visit our Stormwater Work Group page to review meeting agendas, notes, and presentations from the 6PPD Subgroup. 

ADA Accessibility

The Department of Ecology is committed to providing people with disabilities access to information and services by meeting or exceeding the requirements of the Americans with Disabilities Act (ADA), Section 504 and 508 of the Rehabilitation Act, and Washington State Policy #188.

To request an ADA accommodation, contact Ecology by phone at 360-407-6700 or hwtrpubs@ecy.wa.gov. For Washington Relay Service or TTY call 711 or 877-833-6341. Visit Ecology’s website for more information.