Bloomberg Law
June 11, 2021, 7:42 PM

Review of Particulate Matter Air Levels a ‘No Brainer’ for EPA

Jennifer Hijazi
Jennifer Hijazi

Established and new research will fuel the EPA’s fast-track review of current pollution standards for fine particulate matter, though legal action may loom on the horizon, experts and advocates say.

The Environmental Protection Agency announced Thursday it will reconsider a Trump-era decision to leave National Ambient Air Quality Standards, or NAAQS, unchanged for particulate matter, known as PM2.5. The agency will reconvene a specialized panel to help the Clean Air Scientific Advisory Committee review and round up new research within a 2019 Integrated Science Assessment.

From the agency standpoint, taking swift action on considering more stringent levels “is a no-brainer,” said environmental attorney and former Perkins Coie senior counsel Bill Pedersen.

Recent scientific reviews of fine particulate pollution health effects and calls from EPA scientists to beef up PM levels will give the agency the tools they need to do a proper review, said John Bachmann, former associate director for Science Policy and New Programs at EPA’s Office of Air Quality Planning and Standards under multiple administrations.

“It just makes it compelling that we have, not just a little change in the standard, but a significant change,” he said.

Particulate matter, a common and deadly criteria pollutant that includes soot, can come directly from sources such as industrial facilities and fires, or be formed in toxic airborne mixes, causing a slew of health issues and thousands of premature deaths annually in the U.S.

Challenges Ahead

But the agency could be facing legal challenges, “procedurally and on substantive grounds,” in its quick reconsideration of new research on fine particulate matter levels, said David M. Loring, an environmental attorney and partner at Schiff Hardin LLP.

The agency could open itself up to challenges particularly because it “intends to commission a new specialist panel to reconsider its prior 2019 Integrated Science Assessment rather than perform an entirely new assessment,” Loring said in an email.

Balancing the need for quick work with the potential for litigation creates a tough task, according to Gretchen Goldman, research director for the Union of Concerned Scientists’ Center for Science and Democracy.

“The process takes a while, but at the same time, it also needs to be legally defensible,” Goldman said. “They have to cross the T’s and dot the I’s, so that they can make sure that it survives any court challenges.”

Bachmann acknowledged the EPA’s timeline is “aggressive,” adding that “it’s never optimal to have to do things too fast.”

Current Groundwork

Still, advocates and experts say the EPA’s previous analysis of research on the negative health effects of PM2.5 lays a solid foundation for the review.

“It will be very easy for them to say,’ well, we looked at the same data plus the new stuff, and we come out in a different place,’” Pedersen said. “That is the kind of decision that agencies typically get deference on.”

Former EPA Administrator Andrew Wheeler dissolved the agency’s panel of particulate matter experts in 2018, claiming they were no longer needed to assist the Clean Air Scientific Advisory Committee. Two years later, Wheeler’s EPA chose to leave the PM2.5 standards unchanged.

Regardless, members of the disbanded panel, including Goldman and Bachmann, met in 2019 as the “Independent Particulate Matter Review Panel” to move forward with a technical review.

The groundwork from the independent panel and the current integrated science assessment means the EPA won’t have to start from scratch its its review of PM2.5 standards, Goldman said.

“They should be able to hit the ground running,” she said.

To contact the reporter on this story: Jennifer Hijazi in Washington at

To contact the editor responsible for this story: Rebecca Baker at