OAKLAND, Calif.— A federal judge approved a legal agreement today requiring the U.S. Environmental Protection Agency to act on smog pollution in the Phoenix-Mesa metro area by Feb. 3, 2026.

But the agency has proposed excusing Phoenix from taking any action to clean up the dangerous pollution under a rarely used provision of the Clean Air Act that allows exemptions based on emissions from abroad.

The EPA must now give the public an opportunity to comment on the proposal.

“It’s outrageous that the Trump EPA wants to use international emissions as an excuse to do nothing instead of reducing the dangerous smog Phoenix residents are forced to breathe every day,” said Benjamin Rankin, an associate attorney at the Center for Biological Diversity. “People in the Phoenix metro area can push back and demand that the Trump administration act aggressively and urgently to reduce unhealthy pollution rather than pander to the polluters causing it.”

The Clean Air Act requires the EPA to set “national ambient air quality standards” for pollutants such as ozone, commonly known as smog. The EPA set air standards for ozone in 2015, but a decade later it is failing to ensure that Phoenix is reducing ozone pollution to healthy levels.

People exposed to excess ozone are at risk of reduced lung function and increased respiratory problems like asthma, suffering more emergency room visits and premature deaths. Around 4 million people in the Phoenix area are being chronically exposed to ozone pollution caused by industrial and vehicle emissions and extreme heat.

Ozone also causes widespread environmental harms by stunting tree growth, damaging leaves and increasing plants’ susceptibility to disease, insect damage and harsh weather.

“It’s high time that the Trump administration took action to protect people from disease-causing ozone pollution, especially children and the elderly, who are most vulnerable,” said Shakoora Azimi-Gaylon, senior director of toxic exposures and pollution prevention at the Center for Environmental Health. “It’d be a shame if the EPA only stops sitting on its hands just to let Phoenix off the hook for its ozone problem. We must continue to fight for clean air for the millions of people living in Phoenix.”

An EPA study found that Clean Air Act programs to reduce fine particle and ozone pollution prevented more than 230,000 deaths, 200,000 heart attacks, and 2.4 million asthma attacks in 2020 alone. For each dollar spent, Americans have received more than $30 of health benefits in return.

While protecting the health of Americans, the Clean Air Act has also helped to keep the U.S. economy healthy by creating jobs, with an estimated 1.6 million Americans employed in the environmental technology industry helping to keep our air clean.

Today’s agreement between the EPA, the Center for Biological Diversity and the Center for Environmental Health was approved in the U.S. District Court for the Northern District of California. The agreement and the 2025 lawsuit it resolves are part of an ongoing effort to compel the EPA to protect people and the environment from air pollution, including ozone pollution, in compliance with the Clean Air Act.

More information about the fight against air pollution is available at Protecting Air Quality Under the Clean Air Act.