Author: Md. AG Staff     Published: 3/31/2026    Maryland A.G. Press

FOR IMMEDIATE RELEASE: March 31, 2026

Media Contacts: press@oag.state.md.us 410-576-7009

Attorney General Brown Challenges Rollback of Limits on Dangerous Emissions of Mercury and Other Hazardous Air Pollutants from Power Plants 

BALTIMORE, MD – Attorney General Anthony G. Brown joined a coalition of 21 states and local governments in filing a lawsuit challenging the Trump administration’s repeal of the 2024 Mercury and Air Toxics Standards (MATS) Rule and reversion to outdated standards that harm the environment and public health.

“Mercury is a brain-destroying poison that can cause lasting harm to any Marylander who consumes it, especially pregnant people and young children,” said Attorney General Brown. “We are filing this lawsuit to reverse the EPA’s reckless rollback and restore the protections that keep our residents and their families safe.”

The MATS Rule implements nationwide standards that limit emissions of toxic air pollutants from coal- and oil-fired power plants, including mercury, arsenic, lead, and other toxic metals, in addition to acid gases, such as hydrogen chloride and formaldehyde. In 2024, following significant developments in the technologies used to control pollution, the Environmental Protection Agency (EPA) updated the standards for controlling emissions of these hazardous air pollutants from power plants. Last month, the Trump administration rolled back the updated standard, allowing for more of these dangerous pollutants to be released into the air. 

While mercury and other hazardous air pollutants disproportionately harm people who live near coal- and oil-fired power plants, the emissions can also travel great distances and be deposited into other states. Mercury is a potent neurotoxin that poses serious dangers to public health, especially for pregnant women and children. For example, a pregnant person’s consumption of mercury exposes their child to mercury and can cause lifelong developmental harms and neurological disorders such as seizures, vision and hearing loss, or delayed development. Exposure to mercury also increases the risk of cardiovascular disease, diabetes, and autoimmune dysfunction in adults.

Mercury emissions from power plants are also a major contributor to mercury contamination in U.S. waterways. Mercury pollution in lakes and rivers harms the local commercial and recreation fishing economies, as well as tribal nations and indigenous peoples that rely on fishing for subsistence.

Attorney General Brown and the coalition are asking the court to determine that the rule is unlawful and must be reversed.

Joining Attorney General Brown in filing the legal challenge are the attorneys general of Arizona, Connecticut, Delaware, the District of Columbia, Maine, Massachusetts, Michigan, New Jersey, New Mexico, New York, Oregon, Rhode Island, Vermont, Washington, and Wisconsin, along with the city of Chicago, the city of New York and Harris County, Texas.

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