Researchers examined the Medicare claims of 60 million of American 65 and over for 7 years. It concluded pollution standards need to be increased and acceptable levels reduced.
Per the Los Angeles Times
"Critics may claim that stronger standards would offer diminishing returns, but the study results provide new evidence that they would actually increase health benefits, with fewer people getting sick and dying from dirty air, said Francesca Dominici, a data scientist at the Harvard T.H. Chan School of Public Health and the study’s principal investigator.
“We are seeing that the air that we are breathing right now is harmful, it's toxic,” Dominici said.
An editorial that accompanies the study said the findings “stress the need for tighter regulation of air-pollutant levels” and stricter limits on fine particulate matter.
“Despite compelling data, the Trump administration is moving headlong in the opposite direction,” the editorial said, citing the president’s recent steps to dismantle emissions-cutting rules, withdraw from the Paris climate accord and slash the EPA’s budget. “The increased air pollution that would result from loosening current restrictions would have devastating effects on public health.”