The Environmental Protection Agency has rolled back restrictions on mercury, lead, and arsenic emissions from coal-fired power plants, reversing health protections that agency scientists estimate prevent thousands of premature deaths annually.
The decision, announced Thursday, dismantles the Mercury and Air Toxics Standards implemented in 2012 under the Obama administration. Environmental health experts warn the rollback will expose vulnerable populations—particularly pregnant women, children, and communities near coal plants—to neurotoxic pollutants with well-documented health impacts.
"Mercury exposure damages developing brains," said Dr. Jennifer Sass, senior scientist at the Natural Resources Defense Council. "We're talking about permanent cognitive impairment in children, increased cardiovascular mortality in adults. The science on this is unambiguous."
The EPA's own 2011 analysis found the mercury standards would prevent 11,000 premature deaths, 4,700 heart attacks, and 130,000 asthma attacks annually. The agency now argues those benefits are outweighed by compliance costs to the coal industry, despite the fact that 99 percent of coal plants already meet the existing standards.
Coal combustion releases mercury into the atmosphere, where it settles in waterways and accumulates in fish. Methylmercury—the organic form that bioaccumulates through the food chain—crosses the placental barrier and damages fetal nervous systems. The World Health Organization identifies mercury as one of the top ten chemicals of major public health concern.
"This decision ignores decades of toxicology research," said Dr. Philip Landrigan, director of Boston College's Global Public Health Program. "Low-level mercury exposure in utero reduces IQ, impairs fine motor skills, and increases ADHD risk. These are permanent effects."
The rollback arrives as coal-fired generation continues its structural decline across the United States. Coal provided just 16.2 percent of U.S. electricity in 2025, down from 50 percent two decades ago, according to the Energy Information Administration. Renewable energy and natural gas have captured the market share coal has lost, driven by economics rather than regulation.
Environmental justice advocates emphasize that coal plant pollution disproportionately impacts low-income communities and communities of color. A 2021 study in Nature Sustainability found that Black Americans experience 56 percent more exposure to particulate pollution from power plants than they cause through consumption patterns.
"These communities already bear the highest pollution burden," said Mustafa Santiago Ali, vice president of environmental justice at the National Wildlife Federation. "Weakening mercury standards compounds existing health inequities."
The decision contradicts findings from the EPA's own Science Advisory Board, which concluded in 2024 that mercury standards provide substantial public health benefits that justify their costs. Legal challenges from environmental groups and state attorneys general are expected.
California, New York, and twelve other states have indicated they will maintain or strengthen their own mercury standards regardless of federal action. These states account for roughly one-third of U.S. coal-fired capacity.
In climate policy, as across environmental challenges, urgency must meet solutions—science demands action, but despair achieves nothing. The mercury rollback demonstrates how political decisions can override scientific consensus, even when the health evidence is unambiguous and the economic justification is weak.
Public health experts note that mercury pollution crosses state and national boundaries through atmospheric transport. A coal plant in Ohio contributes to mercury contamination in New England fisheries. This transboundary nature of air pollution makes federal standards particularly important.
The coal industry has argued that compliance costs threatened plant viability, yet data show the opposite. Plants that installed mercury controls—primarily activated carbon injection systems—have operated reliably while meeting emission standards. Technology deployment proved less expensive than industry projected in 2011.
"The regulatory cost estimates were inflated," said Dallas Burtraw, senior fellow at Resources for the Future. "Actual compliance costs came in at a fraction of what industry claimed. And the health benefits are enormous."
The timing of the rollback is particularly striking given growing global attention to mercury reduction. The Minamata Convention on Mercury, a United Nations treaty, commits 147 countries to reducing mercury emissions from coal combustion and other sources.
As one of the world's largest historical mercury emitters, the United States had been viewed as a leader in mercury control technology. The EPA rollback signals a retreat from that leadership role at precisely the moment when developing countries are seeking technical guidance on emission control.
The decision will likely survive legal challenge under current Supreme Court precedent, which grants agencies broad authority to reconsider regulatory costs and benefits. However, the next administration could reverse the rollback—as has occurred with mercury standards twice before, creating regulatory uncertainty for utilities.
Environmental health researchers emphasize that mercury's neurological impacts are irreversible. Children exposed in utero to elevated mercury levels will carry cognitive deficits throughout their lives, regardless of future regulatory changes.
"We're not talking about hypothetical risks," said Dr. Sass. "We're talking about measurable IQ loss, documented in dozens of studies. Every year of increased mercury exposure represents another cohort of children with preventable brain damage."
