US regulators to review tire chemical killing salmon

The US Environmental Protection Agency (EPA) will review a chemical used in car tires that is killing salmon. Indigenous tribes on the West Coast of the US requested the EPA's assistance after finding that the chemical, known as 6PPD, is leaching into waterways and causing harm to salmon populations. The chemical reacts with ozone and oxygen in the environment and creates a substance known as 6PPD-quinone, which is toxic to salmon. The tribes have expressed concerns over the impact on culturally significant salmon populations and are urging for action to be taken to prevent further harm.