US EPA launches new review of ozone air quality
Due to the strong US EPA emission standards, which also include ozone, ozone has decreased by 7 per cent between 2010 and 2022. The areas not meeting the 2015 standards need further mitigation action. The EPA has initiated new federal emission standards for cars and trucks and strengthened the rules to reduce volatile organic compounds (a precursor to ozone) from the oil and gas industry, as well as other mitigations. The overall reductions in ozone precursors amount to hundreds of thousands of tons, with estimated health benefits adding up to billions of dollars. The US EPA established current standards at a level of 70 parts per billion in 2015 and retained them at this level in 2020 after concluding that there was little new information to suggest the need for revision. The corresponding Advisory Committee CASAC has now identified studies published more recently and recommended that the EPA conduct additional risk analyses that might support more stringent standards.
Environmental Protection Agency, August 21, 2023