"Today, EPA is issuing the most health-protective national air quality standards in our nation's history," EPA Administrator Stephen Johnson said in a telephone briefing with reporters. "All Americans deserve to breathe clean air, and through these more protective standards that is exactly what we are delivering today."
Under the new rule, which became final with Johnson's signature, the national standard for daily exposure to fine particle pollution will drop from 65 micrograms per cubic meter to 35 micrograms per cubic meter. That's a significant change; under the tighter rules, an additional 32 counties in the U.S. will now have substandard air quality. At the same time, however, the agency decided to leave the annual standards for exposure to fine particles at their current level 15 micrograms per cubic meter.
Basically, the EPA seems to have decided that a compromise on fine particles is better than no movement at all. The science that short-term exposure to fine particle pollution increases the risk of death and illness from asthma, heart attack and stroke is is so overwhelming that the agency had to take action on that front. But there is enough wiggle room in the long-term data that the agency felt it could leave the annual standards where they are.
Public health and environmental groups were quick to call the new rules too lax. According to a report from the American Lung Association, the new rules "leave far too many people at risk of serious harm even premature death from breathing unhealthy, polluted air." The Lung Association, the American Medical Association, the American Academy of Pediatrics and the American Heart Association all favor a daily standard of 25 microgram per cubic meter of air for fine particles and an annual limit of 12 micrograms per cubic meter.