EPA to investigate chemical that tribes blame for salmon deaths

The Environmental Protection Agency (EPA) will review a chemical used in tire production in response to a petition from three Native American tribes who cited its history of killing salmon.

California’s Yurok Tribe and Washington state’s  Port Gamble S’Klallam and Puyallup Tribe petitioned the agency this summer to consider prohibiting the use of 6PPD, a rubber preservative used in most tire production, due to its damage to local salmon populations en route to spawning grounds. 

In the August petition, the tribes, represented by EarthJustice, noted that a byproduct of the chemical, 6PPD-quinone (6PPD-q), is the second most toxic chemical to aquatic species ever recorded by the EPA, second only to the now-banned pesticide parathion.

Exposure to 6PPD-q has been associated with coho salmon deaths within hours, as well as so-called urban runoff mortality syndrome, which kills adult coho before they can return to freshwater waterways to spawn.

“Today, EPA is responding to our Tribal partners by taking action to protect the coho salmon, which are a key part of the Tribes’ cultural identity and economic security,” Assistant Administrator for the Office of Chemical Safety and Pollution Prevention Michal Freedhoff said in a statement.

“These salmon and other fish have suffered dramatic decreases in population over the years. Addressing 6PPD-quinone in the environment, and the use of its parent, 6PPD, is one way we can work to reverse this trend.”  

In its statement, the EPA noted that while some data indicate the chemical is toxic to fish, its effects on human health remain more ambiguous. The agency expects a final rule by the end of 2024.

“The petition is a huge win for ney-puy (salmon) and the planet. The Yurok Tribe got involved because we are a fishing people, who understand the cultural and ecological importance of salmon,” Joseph L. James, Chairman of the Yurok Tribe, said in a statement to The Hill.

“We could not sit idle while 6PPD kills the fish that sustain us. This lethal toxin has no business in any salmon-bearing watershed.”