Health Groups Sue EPA Over Power Plant Mercury Emissions Rule

A coalition of public health and environmental groups filed a petition for review Monday, arguing the EPA’s recent move to weaken power plant emission rules endangers people’s health and lives.

The Environmental Protection Agency’s February rollback of its Mercury and Air Toxics Standards (MATS) rule “will expose more communities to mercury and other toxic pollutants, leading to brain development impacts, asthma attacks, cancers, and premature deaths,” Harold Wimmer, president of the American Lung Association—one of the litigants in the case—said in a statement.

“Our mission is to save lives, and we are taking this action because EPA has retreated from their mission and is putting Americans at risk,” Wimmer said.

The case was filed in the US Court of Appeals for the District of Columbia Circuit.

The MATS rule as finalized in 2024 under the Biden administration tightened the limits for mercury emissions from power plants. The rule also required power plants to install monitoring equipment.

The Trump EPA’s clawback returns the agency to the 2012 standards, which were more lenient on coal-fired power plants. The repeal is scheduled to kick in April 27.

The clawback is part of a broader campaign by the Trump administration to prop up the coal sector, as laid out in an April executive order that framed coal as a key vector for economic prosperity and national security.

EPA Administrator Lee Zeldin has said the move will save Americans $670 million. The agency has also said it’s still enforcing the 2012 MATS rule requirements, which it claims do a good job of balancing public health and environmental protections with economic growth.

But Andrew Racine, president of the American Academy of Pediatrics—another litigant in the matter—said in a statement that the rollback will increase harms to children’s brain development, and that the risks of respiratory conditions like asthma will worsen.

The updated standards have already cut toxic mercury emissions by 90% from the power sector, said Georges Benjamin, CEO of the American Public Health Association, which also joined the petition.

Physicians for Social Responsibility also joined the coalition, which is represented by the Southern Environmental Law Center. Earthjustice represents Air Alliance Houston.

The coalition includes the Sierra Club. The Sierra Club has received funding from Bloomberg Philanthropies, the charitable organization founded by Michael Bloomberg. Bloomberg Law is operated by entities controlled by Michael Bloomberg.

The case is Air All. Houston v. EPA, D.C. Cir., not yet docketed, 3/30/26.