West Coast fishing groups filed a federal lawsuit earlier this month against 13 of the largest tire manufacturers in the U.S., alleging the companies are illegally killing or harming endangered salmon and oceangoing trout by the use of toxic chemicals in their products.

The lawsuit filed in U.S. District Court in San Francisco alleges that the tire-makers violated the U.S. Endangered Species Act through the discharge of 6PPD-quinone, a chemical derived from a preservative that helps tires last longer. The chemical has been linked to mortality in coho salmon returning to Puget Sound streams and, the groups allege, is harming Chinook and steelhead.

The Pacific Coast Federation of Fishermen's Associations and the Institute for Fisheries Resources' complaint outlines two dozen endangered populations of salmonids along the West Coast that have been impacted by the chemical.

In 2020, researchers revealed that the toxic chemical was the culprit behind the deaths of coho in about 40% of the Puget Sound area. The study found it kills 40% to 90% of coho returning to some urban streams before they spawn.

Toxic concentrations of the chemical have been confirmed in watersheds in San Francisco, Seattle and Los Angeles. The National Marine Fisheries Service has identified stormwater runoff as a significant factor contributing to the decline of each of the 24 populations the complaint identifies. The stormwater runoff contains 6PPD-quinone.

Symptoms of acute poisoning among coho salmon have been described in urban streams since the late 1980s. Today, California's Department of Toxic Substances Control has linked a 70% decline in coho in the San Francisco Bay Area between the 1960s and 1990s to the use of the chemical in tires.

These declines related to the chemical, coupled with climate change, and habitat loss related to the damming, diking and channeling of rivers and streams for farming, electricity, drinking water and other human uses, have led to conservation closures of tribal, commercial and recreational fisheries along the West Coast.

The complaint comes on the heels of the Environmental Protection Agency's decision to review the use of the chemical in tires. The Port Gamble S'Klallam and Puyallup tribes and Yurok Tribe, of northern California, asked the agency this year to prohibit the toxic chemical's use.

"We could not sit idle while 6PPD kills the fish that sustain us," Joseph L. James, chair of the Yurok Tribe, told The Associated Press. "This lethal toxin has no business in any salmon-bearing watershed."

The states of Washington, Oregon, Vermont, Rhode Island and Connecticut also wrote the EPA, citing the chemical's threat to their waters and fisheries. Washington state has already begun researching safer alternatives to the chemical and developing methods to test and monitor for the chemicals in the environment.

...continued

©2023 The Seattle Times. Visit seattletimes.com. Distributed by Tribune Content Agency, LLC.