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EPA's Critics Are Wrong: It's Not About Politics

Cass R. Sunstein is a Bloomberg View columnist. He is the author of “The World According to Star Wars” and a co-author of “Nudge: Improving Decisions About Health, Wealth and Happiness.”
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This week’s decision by the Environmental Protection Agency, imposing a new limit on ground-level ozone at 70 parts per billion, was eminently reasonable -- an impressive vindication of both law and science. The loud objections, coming from both the business community and environmental groups, are unconvincing. (Disclosure: As administrator of the White House's Office of Information and Regulatory Affairs, I was involved in the 2011 decision to postpone the ozone regulation.)

Law first: The Clean Air Act requires the EPA to set national ambient air quality standards at a level “requisite to protect the public health” with an “adequate margin of safety.” It also requires the EPA to revisit its standards every five years.

In 2001, a unanimous Supreme Court ruled that when issuing standards, the EPA lacks the authority to consider costs. And consistent with the schedule laid out in the Clean Air Act, a federal court last year required the agency to issue its ozone standard by Thursday.

It follows that EPA Administrator Gina McCarthy, and the Barack Obama administration as a whole, were sharply constrained. As Obama noted last month, “there are some fairly stringent statutory guidelines by which EPA is supposed to evaluate the standards.”

Under those guidelines, the EPA must obtain advice from a board of scientific experts, the seven-member Clean Air Scientific Advisory Committee. In recent years, and with reference to the scientific literature, CASAC has consistently recommended a revision of the current standard of 75 ppb, indicating that science supports a standard between 60 ppb and 70 ppb.

In 2014, CASAC unanimously found “clear scientific support for the need to revise the standard.” Indeed, CASAC added that “a level of 70 ppb provides little margin of safety for the protection of public health, particularly for sensitive subpopulations.”

Reasonably enough, members of the business community do not welcome significant regulatory costs, and have argued vociferously in favor of retaining the 75 ppb standard. Any new standard would indeed be very expensive. But in light of the law and the science, suggesting that a 70 ppb standard would prevent (among other things) hundreds of premature deaths each year, their objections are not strong.

Environmental groups are sorely disappointed; many wanted a standard of 60 ppb. But here as well, the EPA offered an eminently plausible (and impressively technical) explanation. Its central argument is that the evidence of adverse health effects is a lot weaker at the lower end of the CASAC range. Adverse respiratory effects can be found at levels of 80 ppb or higher; at concentrations as low as 72 ppb, healthy young adults, engaged in moderate exertion, have shown decreased lung function and respiratory symptoms.

At 60 ppb, however, no such symptoms have been observed. According to the EPA, scientists have reported no statistically significant increases in respiratory symptoms at either 60 or 63 ppb. At those levels, any adverse effects on lung function have been both short-term and reversible.

CASAC itself concluded that at 60 ppb, the effects “could” be adverse in people with lung disease -- a pretty equivocal conclusion. Hence the EPA found “greater uncertainty” about the nature of adverse effects in the vicinity of 60 ppb.

Importantly, the EPA emphasized that even with a standard of 70 ppb, the new rule will, in practice, end up protecting the vast majority of people (including children) from facing two or more exposures at or above 60 ppb. The agency added that CASAC’s discomfort with a standard of 70 ppb was styled as “policy advice” -- and that the choice of that standard reflected its confidence about the levels at which genuinely adverse effects had been demonstrated.

It is true that in light of the “adequate margin of safety” language, and the existing evidence, there is a good argument that EPA had the discretion to choose a standard of 65 ppb, or even 60 ppb. But would that have been better? Its choice of 70 ppb reflected the strongest evidence of harm to public health. And as the standard is actually implemented, that choice will have the further benefit of ensuring that people will be breathing air that is much cleaner than that.

There is a deeper point in the background. Both business organizations and environmental groups make the same blunder: They see the decisions of the EPA (and other agencies) in crassly political terms, as if public officials are usually responding to pressure and “caving” to one side or another -- or trying to decide whom not to offend.

Nothing could be further from the truth. It might be boring, but most of the time, the goal is to follow the law and the evidence, and to ensure that judgments of substantive policy will turn out, in the real world, to be helpful rather than harmful. (I can report that contrary to newspaper accounts, those judgments, and not politics or lobbying, accounted for the decision to delay the rule in 2011; I suspect that the same is true of this week’s decision.)

Reasonable people can certainly disagree about how the agency exercised its discretion. But from the standpoint of law and science, the EPA got it exactly right.

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.

To contact the author of this story:
Cass R Sunstein at csunstein1@bloomberg.net

To contact the editor responsible for this story:
Christopher Flavelle at cflavelle@bloomberg.net