America’s air is about to get dirtier and more dangerous
The Clean Air Act has saved millions of lives, but the EPA will stop calculating those benefits for at least some proposed regulations.
By Andrea Thompson edited by Claire Cameron

Smog in Denver in January 1974.
Bill Wunsch/The Denver Post via Getty Images
For more than five decades, the Clean Air Act has prevented millions of premature deaths, hospitalizations, and lost work and school days. According to an official 2011 estimate, the Act’s limits on harmful pollution benefited the U.S. economy to the tune of $2 trillion by 2020, compared to $65 billion in costs to implement the regulations.
But today, the U.S. Environmental Protection Agency is abruptly changing how it enforces at least parts of the Clean Air Act by not calculating the economic benefits of some regulations. The seemingly inevitable result is that Americans will soon breathe noticeably dirtier air and experience worse health outcomes, experts say.
“I don’t think anyone wants to go back to…not being able to see anything,” says Camille Pannu, an environmental law expert at Columbia University.
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The EPA will no longer consider the monetary value of lives saved or other adverse effects avoided by imposing limits on fine particulate matter with the PM designation.2.5 or ozone emissions in at least some cases, the New York Times reported Monday. Instead, the agency will only calculate the cost to the enforcement industry of the law.
To understand why this is important, it is important to understand what ozone and PM2.5 do to our body. PM2.5 describes particles with a diameter less than 2.5 microns. They are small enough to enter the bloodstream, lodge deep in the lungs, and cross the blood-brain barrier. PM2.5 has been linked to diabetes, obesity, dementia, cancer, low birth weight and asthma. Ozone, a key ingredient in smog, is particularly dangerous for people with asthma and other lung diseases, especially children.
The Clean Air Act was enacted precisely because the health effects of dirty air extend to the entire population and are difficult to assess. In other words, without estimating costs, even imperfectly, “everything is expensive and nothing is worth regulating,” Pannu says.
In a document reviewed by the New York Times, an EPA official cited language that said the way the monetary value of regulatory benefits was calculated “provided the public with false precision and false confidence.” Yet experts point out that that’s part of the problem: The authors of the law “wanted the EPA to regulate even though the science was uncertain,” says Lisa Heinzerling, an environmental law expert at Georgetown University.
Different presidential administrations have taken different approaches to totaling the value of these benefits, but the science behind these estimates is well established.
For decades, researchers have compared places with higher and lower levels of pollutants and examined differences in premature deaths and other health problems while controlling for other factors that might affect those numbers. These analyzes are then combined with economic studies that estimate the “statistical value of a life” by examining, for example, the amount of lost wages incurred when a parent stays home with a child suffering an asthma attack. Because this work has been going on for so long, that means researchers can be confident in the value they arrive at, says Rachel Rothschild, an environmental law expert at the University of Michigan.

Amanda Montañez; Source: Benefits and costs of US air pollution regulations. Prepared by Jason Price et al. for the Natural Resources Defense Council. Industrial economy, May 2020 (data)
Independent analyzes were also conducted which showed that PM2.5“the damage was so great” and “the benefits [of the Clean Air Act] were so enormous” that they far exceeded the costs of implementing the law, Rothschild says. The Clean Air Act regulations “pay for themselves; they pay for the full EPA,” Heinzerling acknowledges.
A 2016 analysis by the University of Chicago found that Americans had gained 336 million years of lifea measure of how long people are expected to live in good health, since amendments to the Clean Air Act were passed in 1970. And in 2011, the EPA estimated that updates to the law made in 1990 would allow prevent more than 230,000 premature deaths75,000 cases of bronchitis, 120,000 emergency room visits and 17 million work days lost by 2020. About 85 percent of these benefits come from deaths avoided through reductions in specific cases alone.
Cost estimates are also inherently uncertain. And according to Rothschild, past EPA analyzes have almost always found that the agency overestimated these costs. She and others expect the decision to be challenged in court.
It is also unclear to what extent this new policy can be applied. Documents cited by the The New York Times reports suggest it will apply to proposals from the agency’s Office of Air and Radiation, with consequences including repealing limits on greenhouse gas emissions. THE Times also cited language similar to that mentioned in EPA emails in a regulatory impact analysis published Monday regarding limits on nitrogen dioxide and sulfur dioxide from combustion turbines in gas-fired power plants. Such facilities are in high demand in data centers to meet their considerable power requirements.
The EPA is legally required to provide its rationales and any data it relies on to make such decisions, Heinzerling says.
In a statement in response to detailed questions from Scientific American, An EPA spokesperson said the agency continues to review the impacts of particulate matter.2.5 and ozone on human health, adding that “the agency will not monetize the impacts at this time.”
“EPA is fully committed to its core mission of protecting human health and the environment,” the statement continued.
The EPA spokesperson also noted that the previous Biden administration did not calculate the value of the health benefits of certain Clean Air Act rules, including for PM.2.5. Rothschild says some past administrations may not have quantified the benefits of each proposed regulation, especially those that were very difficult to calculate. But, she says, “the health benefits resulting from particulate matter and ozone reduction are among the easiest to quantify and monetize of all types of environmental pollution.”
“It is disappointing that the EPA is not interested in making the best decision for the public,” Rothschild says.



























