Final Determination from EPA: Enormous Health Benefits from Cost-Effective Mercury and Air Toxics Standards

Agency Finalizes its Determination that Reducing Hazardous Air Pollution is Appropriate in Light of Costs

April 15, 2016
Sharyn Stein, 202-572-3396,

(Washington, D.C. – April 15, 2016) The U.S. Environmental Protection Agency (EPA) today finalized its determination that the Mercury and Air Toxics Standards are appropriate in light of costs, and in the process reaffirmed the enormous public health benefits of reducing mercury, arsenic, acid gases and other toxic air pollution.

EPA’s limits on these hazardous contaminants are one of the most important public health safeguards adopted in the history of our nation’s clean air laws. Today’s action is in response to a June 2015 Supreme Court  opinion written by Justice Antonin Scalia, when a sharply divided Court ruled 5-4 that EPA must consider the costs of regulation in making its threshold determination whether it is “appropriate and necessary” to regulate hazardous air pollution from power plants. EPA had considered costs in establishing the resulting emissions standards.  

“EPA’s landmark safeguards address the scourge of mercury and other toxic smokestack pollution in our air, our water and our food. Today’s final finding confirms that the Mercury and Air Toxics Standards are a vital and highly cost-effective investment in cleaner air and a safer environment for our communities,” said Graham McCahan, Senior Attorney for Environmental Defense Fund, which was a party to the case. “The enormous health benefits of the Mercury and Air Toxics Standards are based on the strongest possible science. EPA’s analyses also show these protections are clearly cost effective.”

The Mercury and Air Toxics Standards set the first-ever national limits on hazardous air pollutants — including mercury, arsenic, chromium, and hydrochloric acid gas — from power plants, the largest source of those pollutants. 

The pollutants covered by the Mercury and Air Toxics Standards are dangerous to human health even in small doses—mercury causes brain damage in infants and children, metal toxics like chromium and nickel cause cancer, and acid gases cause respiratory problems. When fully implemented, the Mercury Standards will prevent up to 11,000 deaths and tens of thousands of other serious health problems each year.

When EPA wrote the Mercury and Air Toxics Standards in 2011, it found that the public health benefits of the Mercury and Air Toxics Standards were up to $90 billion annually, and far exceeded compliance costs. However, the Supreme Court found that EPA should have also considered the costs in its initial, or threshold, decision to regulate these hazardous pollutants. 

The Court did not overturn the Mercury and Air Toxics Standards, but it remanded them to the D.C. Circuit Court of Appeals. Both the D.C. Circuit and the Supreme Court refused to vacate the standards while EPA performed its consideration of costs, so the standards have already started protecting Americans from dangerous pollutants. And since 2011, major power companies have dramatically reduced their estimates of the costs to comply with the Mercury and Air Toxics Standards, while the body of scientific evidence supporting them has grown. 

In today’s final finding, EPA has fulfilled the directives of the Supreme Court. Based on a thorough and careful analysis, today’s finding confirms that the cost of compliance for the Mercury and Air Toxics Standards is eminently reasonable when considered in light of the serious public health and environmental hazards of toxic emissions from power plants:

“[EPA’s approach] places value on the statutory goals of achieving prompt, permanent, and ongoing reductions in significant volumes of [hazardous air pollution] and on the important, and, in many cases, unquantifiable advantages of reducing the significant hazards to public health posed by such emissions, including addressing the risk to the most exposed and most sensitive members of society.” (Finding, Page 6)

You can find more about the Mercury and Air Toxics Standards, including all legal briefs, on EDF’s website.

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