Today the nation enjoys far cleaner air than it did 50 years ago when the Clean Air Act was signed into law. But it isn’t clean everywhere. In fact, the quality of the air you breathe depends on where you live, and there are huge discrepancies in air quality across states, within cities, and between neighborhoods. Why is this? How can such differences exist when the law is the same across the country? The reasons are many, but one thing is clear: the laws are not enough, and the Trump administration’s new draft rule on ozone provides a telling example of how the Clean Air Act can fail to protect those who need it most.
A science-based law and the challenge of protecting at-risk populations
To be clear, we’ve made remarkable gains in clearing the air since 1970, due in no small part to the architects of the original law and its 1990 amendments, who enshrined the law with teeth—scientific teeth, that is. Several parts of the law, most notably the National Ambient Air Quality Standards (NAAQS), require that decisions on air quality be based on science and science alone. And they built in mechanisms by which the agency solicits external science advice and synthesizes new science on a regular basis. This process has allowed the agency to set health-protective and science-based standards for decades—even under tremendous pressure from political leaders and industries to set weaker ones.
The Clean Air Act also provides mechanisms for addressing disproportionate impacts and protecting vulnerable populations, but those parts of the Clean Air Act have decidedly fewer scientific teeth (if any). On hazardous air pollutants, for example, the EPA assesses and works to address any excessive (“residual”) risk that communities face after major pollution sources employ the best control technology available, but the agency is limited by capacity, by air quality monitoring and modeling capabilities, and by resources available. The result is that some communities still face greater hazardous air pollution exposure than others, and these are disproportionately communities of color.
Or let’s take the NAAQS. The Clean Air Act requires the EPA to set ambient air pollution standards “requisite to protect public health with an adequate margin of safety” every five years. That margin of safety is designed to ensure that more vulnerable populations are protected. Air pollutants, including ozone and particulate matter, tend to affect sensitive groups more. Thus, adequate margin of safety is designed to ensure that at-risk groups such as the elderly, children, and those with lung diseases are protected in addition to healthy adults. But while setting the ambient pollution standards must be based on science, the decision about what provides an adequate margin of safety is considered a policy decision left to the administrator. This arrangement means that sensitive populations haven’t always been protected by NAAQS standards—and the Trump Administration’s current ozone proposal proves it.
The Trump administration’s ozone draft rule
Ground-level ozone is a persistent and problematic pollutant. It forms in the atmosphere from natural and manmade sources in the presence of sunlight, making it harder to control than pollutants that come directly from a tailpipe or smokestack. Yet, we must control it because ozone exposure aggravates the respiratory system and causes thousands of asthma attacks, missed school days, and missed workdays every year in the US.
The Trump administration has issued a draft rule on ozone, based on a flawed and expediated process that EPA political leadership jammed through with only minimal scientific input. They failed to form an Ozone Review Panel—a group of some two dozen experts that historically have helped ensure a robust review of the science. The result is that the agency and the public missed out on the robust scientific discussion that we deserved to have on such a complex and harmful pollutant. We now have a draft ozone rule that retains the status quo. This, of course, is better than a weaker standard that the administration could have attempted (especially given former Administrator Pruitt’s attempt to delay implementation of the 2015 ozone standards based on “insufficient scientific evidence”). But here’s why retaining the standard is problematic for public health, especially for at-risk groups.
For the previous two cycles, the Clean Air Scientific Advisory Committee (CASAC)—the EPA’s primary source of science advice on NAAQS review—recommended a primary 8-hour maximum ozone standard of 60-70 ppb. In 2015, the science advisors noted in their final letter to the EPA administrator that a standard of 70 ppb might not be protective for sensitive groups, noting that a 70-ppb standard would still mean “substantial scientific evidence of adverse effects … including decrease in lung function, increase in respiratory symptoms, and increase in airway inflammation.” The standard was finalized at 70-ppb anyway.
When the next ozone standard review started in 2018, this should have been a primary point of discussion. Is 70 ppb protective of at-risk group? Is there new evidence to inform that question? Unfortunately, the Trump administration didn’t give us a chance to have that conversation, with no Ozone Review Panel (which undoubtedly would have included several ozone and health effects researchers), and lower scientific expertise on CASAC, we were deprived of what is normally a robust public peer review of the strength of the scientific literature. The lone CASAC member with direct expertise in this area acknowledged questions about whether a standard of 70 ppb would protect asthmatic children, for example. But here we are. We have a proposed rule that fails to consider this risk in any meaningful way and an administrator with a record of disregard for science, process, and protection of vulnerable groups.
Our air pollution policies must be better
The bottom line is that our laws are insufficient to protect vulnerable populations and address disparities in exposure to air pollution. The resulting health consequences are dire, with thousands sickened or killed each year. We must do better. We must protect those who need it most. We can’t depend on laws alone, and we certainly can’t depend on Administrator Wheeler.
The Trump administration’s draft ozone review is now out for public comment. Join me in telling the administration, in written or oral comments, that this rule was produced using an illegitimate process with inadequate scientific review. Communities everywhere deserve better.
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