What To Expect at the Independent Particulate Matter Review Panel Meeting

October 9, 2019 | 9:13 am
Gretchen Goldman
Former Contributor

This Thursday, the 20-member Independent Particulate Matter Review Panel will reconvene—on the anniversary of being disbanded by the EPA—to ensure that independent, robust science advice will inform the EPA’s review of the National Ambient Air Quality Standards for Particulate Matter.

The unprecedented event, hosted by the Union of Concerned Scientists, will be held this Thursday, October 10, and Friday, October 11 in Arlington, Virginia and will be livestreamed (links for day 1 and day 2). Here is what you can expect from the two-day meeting of these top particulate pollution experts, who the EPA thought would just go away.

Why does particulate matter matter?

When you think of air pollution, tiny particles might not be the first thing you think of, but they perhaps should be. Particulate matter—liquid or solid particles much smaller than the width of a human hair—is responsible for more death and sickness in this country than any other air pollutant. Because the Clean Air Act requires the EPA to protect public health, the agency has set standards that have resulted in substantial reductions in particulate pollution in the US over the past few decades.

These standards have been increasingly effective because the agency is required to revisit the standards and the science supporting them every five years. And that science continues to evolve, in part because of the increased monitoring and research stimulated by the standards. Improved measurements and methods to characterize exposure enable improved studies to detect adverse health and welfare effects. The EPA is now reviewing the particulate matter standards that were set in 2012 and determining whether they need to be revised to protect public health.

The role of independent science advice

Science advice on the particulate matter standards plays a crucial role in ensuring we end up with health-protective particulate matter standards; yet last October the EPA leaders gutted the process.

By law, the EPA administrator must receive science advice from the seven-member Clean Air Scientific Advisory Committee (CASAC). However, from the creation of the first CASAC in 1978, the EPA recognized that seven people are not enough to cover the breadth, depth, and diversity of scientific expertise needed for complex air pollution science assessments. Thus the reviews have always been augmented with pollutant review panels to bolster expertise on the pollutant of interest. Based on that four decades of precedent, EPA empaneled a group of about 20 independent scientific experts in 2015 to augment CASAC in the current review.

In 2018, the administrator shook up the seven-member CASAC with new, inexperienced appointees and disbanded the particulate matter review panel. By eliminating the panel, the EPA cut off their best source of independent science advice on particulate matter.

That’s why this reconvening of the panel is so important. By law, the EPA must follow science advice in setting the standard, but the agency has hamstrung its ability to get that advice without the panel. Collectively, the Independent Particulate Matter Review Panel has far more expertise on this topic than the current CASAC. By donating their time and expertise to inform the EPA—despite being disbanded by the very agency they are advising—the panel is ensuring robust, independent science can continue to inform air pollution standards.

What to expect at the meeting

At the meeting of the Independent Particulate Matter Review Panel this week, the group will discuss the science-policy considerations that should inform a decision of whether to retain or revise the particulate matter standards—just as they would have done if they hadn’t been disbanded. This time, the meeting isn’t being run by the EPA, and they won’t be joined by CASAC. The meeting, however, will be run the same way as a CASAC meeting.

The experts have undergone ethics review by the former director of the EPA Science Advisory Board staff office. The panelists will deliberate in public according to the same administrative procedures. And the panel’s advice will be shared with CASAC at their meeting on October 22 and October 24-25 and sent in a letter to the EPA administrator.

After receiving oral and written public comments, the panel will spend the bulk of their two-day meeting going over “Charge Questions” that pertain to their review of EPA’s draft Policy Assessment document. The Policy Assessment “bridges the gap” between the science contained in the earlier EPA Integrated Science Assessment and the evaluation of whether the current particle standards protect public health and welfare, and, if not, what is the range and nature of policy alternatives that should be considered. Charge questions written by EPA staff guide the general areas of science advice that the agency staff believe would be most valuable in setting the standards.

The Independent Particulate Matter Review Panel will address those broad questions, but also will examine “Supplemental Charge Questions” (SCQ). These questions have been added to ensure the panel is responding to more specific scientific and technical issues that inform key science-policy decisions. Finally, the panel has also included some “General Charge” (GC) questions which are derived from former EPA Administrator Scott Pruitt’s “Back to Basics” memo on reforming the National Ambient Air Quality Standards.

The agenda

First, the panel will discuss the degree to which the EPA has adequately characterized the available evidence in the earlier EPA Integrated Science Assessment. In December 2018 and again in March 2019, the panel deliberated and delivered its advice to CASAC and the EPA on the EPA’s draft Integrated Science Assessment.

One area to watch is when the panel discusses the draft Policy Assessment’s provisional conclusions on whether the current primary standard for fine particulate matter, or PM2.5, adequately protects public health. This is an important conversation in any PM standard review but it is especially important now given the current state of the science. The draft Policy Assessment provisionally concludes that the current PM2.5 primary standards may not adequately protect public health. It reads, “The available scientific evidence … can reasonably be viewed as calling into question the adequacy of the public health protection…” The draft assessment also presents a range of alternatives that would strengthen the standards. It will be important to see what the panel concludes on these provisional conclusions and recommendations.

The panel will also discuss the primary PM10 standard—the standard that protects public health from particulate matter less than 10 micrometers. PM10 includes larger particulates than PM2.5 and there are different considerations for how to protect people from this pollutant. Next, the panel will discuss the secondary standards, which include other reasons we need to control air pollution—in this case, impacts on visibility, materials, and climate. The panel will also look at areas where additional research is necessary. This is an important step because it helps ensure that new scientific work can be focused on answering policy relevant questions.

What’s next?

By the end of the second day, the panel plans to have discussed the key points that will comprise a letter they will send to CASAC and the EPA administrator outlining their recommendations for the particulate matter standards. They will hold a public follow-up teleconference on October 18, 10 am – 2 pm EST, to discuss a draft of the letter. If finalized in time, the letter will also be shared at CASAC’s public meeting on October 22. When ready, the letter will also be sent to the EPA administrator and to the official regulatory docket for this review.

The letter will ensure that the EPA administrator receives the same robust, independent science advice from the nation’s top experts that it always has on ambient air pollutant standards. The decision about where air pollution standards are set ultimately lies with the EPA administrator. If he follows the advice of the independent panel, the nation will enjoy standards that are likely to protect public health and welfare. If the administrator sets the standards elsewhere, he can expect outcry from the scientific community (and expect to hear from the legal community). But he certainly won’t be able to claim he didn’t have adequate science advice.