EPA scientists have estimated exposure at current limits causes the early deaths of tens of thousands of Americans annually.
The Trump administration on Monday made final its decision to leave limits for a deadly kind of air pollutant unchanged, overriding scientific findings that tougher standards could save tens of thousands of lives yearly.
Environmental groups and many scientists have condemned the decision, slated to be among the final actions of an administration that targeted most proposed and many existing health and environmental protections as a burden to businesses. In the coal state of West Virginia, officials welcomed Monday's announcement by Environmental Protection Agency administrator Andrew Wheeler, who was a lobbyist for coal immediately before coming to the Trump EPA.
The tougher air standards called for by many scientists in and out of the federal government "could have been a huge blow to the coal industry," Douglas Buffington, West Virginia's senior deputy attorney general, told reporters.
Wheeler's decision leaves unchanged limits for what is broadly called "fine particulate matter" – the tiny bits of soot we breathe in unseen from tailpipes, wildfires, factory and power plant smokestacks, and other sources.
EPA scientists have estimated exposure at current limits causes the early deaths of tens of thousands of Americans annually from heart disease and lung cancer, as well as causing other health problems.
"Their callous disregard for the lives of people and imperiled wildlife, just to save the nation's biggest fossil fuel polluters a few bucks, is sickening," Robert Ukeiley, a senior attorney at the Center for Biological Diversity advocacy group, said of the EPA's move.
Wheeler on Monday said the country's levels for the invisible, deadly pollutant were better than the global average.
Environmental groups promised a legal challenge to Monday's action, which makes official a decision earlier announced by Wheeler. The decision was part of a five-year review of limits required under the Clean Air Act.