EPA regulates emissions of mercury, arsenic and many other toxins

Finally, some sanity regarding smokestack emissions. After decades of political squabbling, on Wednesday the U.S. Environmental Protection Agency issued its Mercury and Air Toxics Standards, or MATS, which will dramatically cut the amount of highly toxic mercury and about 70 other pollutants released in the United States. The rules target the emissions from coal-fired power plants.

Mercury is the key element addressed by these rules, but it’s only one of many chemicals -- plus fine particulate matter, which plays a role in asthma and other respiratory illnesses nationwide -- that are regulated by MATS. Stack emissions from power plants were not regulated for most of these toxins until this ruling. The coal and power generation industries have lobbied fiercely -- and successfully -- against regulations since they were required by amendments to the Clean Air Act in 1990. Even in the last few months, a utility trade group tried again to delay implementation by another year, but failed.

Mercury, in particular, is a powerful poison that affects pregnant women and their babies, resulting in lowered IQ, reduced attention span, memory impairment and other effects in exposed infants.

“Mercury is emitted into the atmosphere and then gets deposited into ecosystems, where it gets converted into methylmercury in aquatic environments, that’s the toxic form, and is accumulated in fish that are then consumed by humans. So we’re mostly concerned about the effects on humans, and particularly pregnant women and children who eat fish high in methylmercury,” says Noelle Selin, assistant professor of engineering systems and atmospheric chemistry at MIT, who studies distribution and health effects of mercury.

Studies cited by Selin state that 300,000 to 600,000 children are born in the U.S. each year with blood levels of methylmercury above the EPA’s safety threshold. EPA studies have also shown that anglers, Asian Americans and Native Americans are at higher risk, as these populations eat more fish out of streams and lakes, particularly in the Midwest and Northeast, which are downwind of more coal-fired plants.

The MATS rules are not pussyfooting: They aim to reduce mercury released into the atmosphere by 91%. The standards also require dramatic reductions in other heavy metals, including arsenic, cadmium, hexavalant chromium, nickel and lead -- all dangerous toxins. Also regulated are acid gases, including hydrochloric acid and hydrofluoric acid, which contribute to acid rain and are known carcinogens. Previously existing sulfur dioxide and nitrous oxide standards are also updated and tightened.

Pollution control technology required to remove mercury from power plant emissions would also control most of these other toxins. A dozen states have heightened their emissions standards well ahead of these new rules and have proved that the regulatory goals are within reach.

“There’ve been proposals for a long time to regulate these emissions from coal-fired power plants. The earlier incarnation of this was the Clean Air Mercury Rule, which was a cap-and-trade proposal for mercury, and that was challenged in the courts and then thrown out. And now this is another try at regulating, but it’s been a long time in coming,” said Selin.

The EPA estimates that the improvements to health by controlling these toxins and fine particulate matter, as measured by reduced heart attacks, bronchitis, asthma, cancer and other illnesses, will save a total $59 billion to $140 billion in healthcare costs in 2016, the year all existing power plants will have to comply. That is $5 to $13 in health benefits for every dollar spent to reduce pollution.

Still, consumers have hard choices to make in order to reduce their mercury exposure. A study by Selin and other researchers found that most of the fish consumed in the U.S. is commercially caught, such as tuna and swordfish, which are ocean species not likely to be greatly affected by mercury reductions only in the U.S. Global regulation is needed to make all fish safer to eat.