EPA tightens standard for fine particles

For the first time in over a decade, the US Environmental Protection Agency has updated the standard for fine particulate matter, known as PM 2.5 . The new rule lowers the acceptable limit of PM 2.5 from an annual average of 12 μg/m 3 to 9 μg/m 3 . PM 2.5 is "one of the most dangerous forms of pollution," EPA administrator Michael S. Regan said during a call with reporters. Small enough to penetrate deep into the lungs, these particles are linked to a slew of adverse health effects, including asthma, lung disease, and heart attacks. According to the EPA, the updated standard will prevent 800,000 cases of asthma, 4,500 premature deaths, and 290,000 lost workdays by 2032. The action "is a critical step forward that will better protect workers, families, and communities from the dangerous and costly impacts of fine particle pollution," Regan said. Environmental groups and health