A science brief for journalists co-authored by Science Policy Exchange co-founders Kathy Fallon Lambert and Charley Driscoll reports that the Environmental Protection Agency is threatening to unravel the Mercury and Air Toxics Standards, federal rules that are reducing mercury pollution. The brief was released by the Harvard Center for Climate, Health, and the Global Environment. 

Virtually all fish from U.S. waters now have detectable levels of methylmercury, due to pollution from burning coal. Methylmercury is a potent neurotoxin. Some fish, such as swordfish, large species of tuna, and freshwater game fish, can have levels that exceed consumption guidelines.

Coal-fired power plants are the largest source of mercury in the U.S., accounting for approximately 48% of mercury emissions in 2015. The Mercury and Air Toxics Standards were finalized in 2012 to regulate emissions of mercury, acid gases and other hazardous air pollutants from U.S. electric utilities.

On April 16, 2020, the Environmental Protection Agency  made a decision that legal scholars say undermines the foundation of the Mercury and Air Toxics Standards rule and invites challenges to the emissions standards themselves. The Environmental Protection Agency deemed that it is not “appropriate and necessary” to regulate mercury and other hazardous air pollutants from oil- and coal-fired power plants under section 112 of the Clean Air Act. 

The Mercury and Air Toxics Standards have been effective at reducing mercury pollution. Rolling back these rules could lead to an increase in mercury pollution, which is particularly harmful for children.