A stormwater priority: Protecting coho salmon from tire chemicals

Coho salmon in urban areas were dying from stormwater runoff, but scientists didn’t know why until a few years ago.

A team of researchers from Washington State University and University of Washington identified a chemical found in tires as the culprit. 

Tires contain 6PPD, which keeps the rubber from cracking after exposure to ozone in the atmosphere. But 6PPD also reacts with ozone, forming the organic chemical 6PPD-quinone. 

During rainstorms, tire dust washes into rivers and streams, where 6PPD-quinone is lethal to juvenile and adult coho in small doses. It’s a complex issue—with no easy fix.

Caitlin Lawrence and Nathan Ivy are master’s students studying aquatic toxicology at WSU’s School of the Environment. Washington State Magazine science writer Becky Kramer talked with them about their separate research projects related to coho and 6PPD-quinone.

Links and resources mentioned in this episode

Puget Sound Starts Here

Washington Stormwater Center

The podcast music is by WSU emeritus professor of music and composer Greg Yasinitsky.

Support the show

______________________________________________________________________________
Want more great WSU stories? Follow Washington State Magazine:

• LinkedIn @Washington-State-Magazine
• Bluesky @wastatemagazine.bsky.social
• X (formerly Twitter) @wsmagazine
• Facebook @WashingtonStateMagazine
• Instagram @WashingtonStateMagazine
• YouTube @WashingtonStateMagazine
• Email newsletter

How do you like the magazine podcast? What WSU stories do you want to hear? Let us know.

Give to the magazine