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Tighten particulate limit, advisers to US EPA say in draft report

by Cheryl Hogue
February 13, 2022 | A version of this story appeared in Volume 100, Issue 6


Skyline of Salt Lake City in winter with hazy air.
Credit: Shutterstock
Salt Lake City experiences high levels of particulate matter air pollution in winter.

To protect the health of US residents, the Environmental Protection Agency should ratchet down the limit for airborne particulate matter, a panel of scientific experts says in a draft report. Breathing in particulates that are 2.5 µm or less in diameter (PM2.5) is associated with heart attacks, decreased lung function, asthma attacks, and premature death in people with heart or lung problems. In its draft report, the EPA’s Clean Air Scientific Advisory Committee says it concurs with an agency assessment released last year that concludes, “Meaningful risk reductions will result from lowering the annual PM2.5 standard.” A majority of the panel recommended a limit of 8–10 µg/m3 of air; the current standard, set in 2012, is 12 µg/m3. Under former president Donald J. Trump, the EPA proposed in 2020 to maintain that standard rather than tighten it as agency staff members had recommended. The chemical industry group American Chemistry Council backed the Trump plan, saying further controls weren’t needed because US air quality is improving. In its draft report, the advisory committee says, “The [scientific] literature, as it is expanding, continues to show strong associations with health effects, even though concentrations of PM2.5 in the air have been dropping over time.” The panel will finalize the report in the spring.


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