EPA 2023 Proposed Soot Exposure Regulation

In January 2023, EPA proposed a reduction of the allowable annual exposure to industrial soot pollution, and will solicit public comment before making a final decision in 2023. EPA’s proposal would lower the annual PM2.5 limit from an average of 12 µg/m3 (set in 2012) to somewhere between 9 and 10 µg/m3, though the agency states it will consider limits between 8 and 11 µg/m3 as well.

In a study cited by EPA, 10 µg/m3 is associated with 1,700 lives saved over the current limit; 9 µg/m3 with 4,200 lives; and 8 µg/m3 with 9,200 lives. The World Health Organization has published guidelines calling for 5 µg/m3 of annual exposure.

Soot comes from many sources, like coal-burning power plants, diesel engines, and tobacco smoke, and is linked to a wide array of health harms including pulmonary and cardiovascular diseases.

The standards themselves don’t directly set limits on any particular pollution source. Instead, they serve as a national guideline that can trigger EPA actions to ensure the air quality requirement is being met across the country.