Car tire chemicals are killing salmon and steelhead
Last year, a group of Washington researchers pinpointed the cause of these mass fish kills [in Pacific Northwest streams]: 6PPD, a chemical added to tires to prevent them from breaking down. When 6PPD, which has been used in tires since the 1970s according to the U.S. Tire Manufacturers Association, reacts with ozone in the atmosphere, it creates 6PPD-quinone (6PPD-q), a compound that leaches into urban stormwater and watersheds. This derivative chemical has proven difficult to identify and study and is even harder to regulate given that the chemicals in tires are proprietary and not disclosed by tire manufacturers. However, new research led by NOAA scientists found 6PPD-q harms other species in the salmonid family besides coho, including steelhead trout.