Roadway runoff in the Columbia river basin

Have you taken any medications today? Washed your car or changed its fluids fluids recently? Or even just ridden in a vehicle? Everything that we put down the drain, both in our homes and in the streets, eventually flows into a body of water.

With more people living in and visiting Astoria, Warrenton, and other places around the Lower Columbia River there are more chemicals coming out of our pipes and sewers than ever before. In 2022 the NCWA received funding to test runoff at 15 sites around our service area, looking for many different contaminants including personal care products (like medications), industrial chemicals, and the newly-discovered 6ppd-Quinone.

what is 6ppd-quinone?

6ppd-Quinone, or 6ppd-Q, is a transformation product of chemical called 6ppd, which is a rubber preservative. This preservative has been added to most all rubber products, from car tires to the soles of shoes, since it was discovered in the 1970s. It prevents that deep cracking you see in old rubber hoses or tires by keeping oxygen or ozone molecules from reaching the rubber. This makes your car tires last a whole lot longer—many thousands of miles more, which is great! What isn’t great is what happens next.

Like all things, tires break down over time, small or even microscopic pieces fall off as you drive around. Those pieces have 6ppd on them, and that 6ppd does its job, it plays with oxygen to distract it from the rubber and in that process it creates a new chemical: 6ppd-Quinone.

This new chemical, the byproduct of 6ppd interacting with oxygen, was discovered in 2019 when scientists around the Puget Sound were searching for answers as to why salmon returning to their urban streams were dying before they could spawn. The answer is that 6ppd-Q is the deadliest toxin to fish, specifically to Coho salmon, that has been discovered to date.

is local water contaminated?

The NCWA tested water coming off roads (outfall) and stream water below these roads during rain events throughout 2023 and 2024. Here is a map that shows where we detected 6ppd-Q in stream water. All samples taken of outfall tested positive for 6ppd-Q.

we are currently working with our partners to conduct more analysis on this data. stay tuned!

for more information about our roadway runoff monitoring

Contact Kelli at kelli@northcoastwatersheds.org

You can also listen to a Watershed Moments podcast episode about 6ppd-quinone here. (November 25th, 2024 episode)