Exposure to mercury is dangerous. In adults, high levels of mercury can cause heart disease as well as severe damage to the brain and central nervous system. For fetuses and babies, it can cause significant developmental delays and possibly lower I.Q. scores and impaired motor skills.
When coal is burned, it releases mercury into the atmosphere. Rain and snow can carry the mercury to the ground, where it can settle in waterways and can accumulate in fish and other aquatic organisms. The most common cause of mercury poisoning is ingesting it from contaminated fish and seafood.
The E.P.A began regulating mercury from coal plants in 2012. Within five years of taking effect, the restrictions caused mercury emission from the power sector to drop 86%. Coal plants are still the single largest source of mercury pollution in the United States, accounting for more than 42% of total emissions. More stringent limits on mercury and other toxic pollutants from coal plants were set by the Biden administration in 2024.
These newer limits have now been repealed by the Trump administration in order to help the coal industry. The change relaxes limits on mercury, cadmium, chromium, and nickel released by burning coal. The argument is that these limits make it more expensive for many coal plants to operate. According to the administration, this is an important step toward ensuring coal-based generation can continue supporting the nation’s economy and electric grid. This is despite overwhelming scientific evidence that burning coal is harming public health and driving dangerous levels of global warming. Coal is the dirtiest of the fossil fuels.
