By TONY COX at the Wall Street Journal
This fall the Environmental Protection Agency plans to take its next grand regulatory step, following the announcement of the EPA’s Clean Power Plan over the summer. The agency is likely to introduce stringent new standards for ground-level ozone, arguing that a lower allowable level of ozone—an important component of smog—will reduce asthma in the U.S., among other claimed health benefits. Yet the EPA ignores decades of data and studies, some under the agency’s auspices, that reveal no detectable causal relation between past reductions in ozone and better public health, including reductions in asthma cases.
The new regulation may be the most expensive ever for the U.S. economy—even worse than the Clean Power Plan’s effect on coal-fired power plants. Some studies, such as one published in August by National Economic Research Associates, estimate implementation costs of hundreds of billions of dollars a year in the short run, and trillions of dollars over the next two decades, as well as millions of lost jobs. Why would it be so costly? Because attacking ozone involves almost every facet of the economy—as the EPA notes, “automobiles, trucks, buses, factories, power plants” and “consumer products” all contribute to ground-level ozone.
So it is important to be clear about what health benefits, if any, such costly reductions in ambient, or surrounding, ozone levels are known to cause.
No one disputes that while average levels of ozone have fallen significantly across the nation since 2000, the number of asthma sufferers has increased. Yet advocacy and lobbying groups such as the Natural Resources Defense Council and the American Lung Association claim that cutting ozone in the future will reduce asthma. The Obama White House blames increasing numbers of asthma patients on climate change.
The National Institutes of Health lists neither climate change nor ozone as a cause of asthma. It notes that the exact causes are unknown, with excessive hygiene in childhood (and resulting underdeveloped immune systems) being investigated as a hypothesis. Assertions that ambient ozone causes asthma have been criticized by many state air-quality regulators, including those inTexas, Ohio, Indiana and South Dakota.
Undaunted, the EPA forges on. Its website notes “an association between ozone levels in the outdoor air and increased hospital admissions for respiratory causes, such as asthma.” The website ignores how much of this statistical association is explained by noncausal factors, such as seasonal variations in weather and pollen that affect both asthma and ambient-ozone levels.
Nonetheless, as urged by environmental lobbyists, the Obama administration is now considering cutting the National Ambient Air Quality Standard for ozone even further than it had originally planned, from a concentration of 75 parts per billion to as low as 60 parts per billion. In many locations, that is close to the naturally occurring background levels of ozone—which is formed when sunlight falls on nitrogen oxides (naturally formed by bacteria, volcanos and lightning), together with volatile organic compounds emitted by trees and other natural sources.
The EPA’s prediction that reducing the man-made ozone level will reduce human suffering from asthma and other respiratory diseases is largely based on new and unproven statistical modeling that, in the EPA’s own words “is convenient for fitting the model, but is not accurate.” The conclusions from this inaccurate modeling are supported by the subjective opinions of experts from institutions that have received tens of millions of dollars of EPA funding (although their researchers routinely declare no conflict of interest or competing financial interests). These experts maintain, along with ranking Democrat on the House Energy and Commerce Committee Rep. Frank Pallone, that reducing ozone will “save lives” and cause improvements in public health in the future—even if it hasn’t done so in the past.
Fortunately, there is abundant historical data on ozone levels and asthma levels in U.S. cities and counties over the past 20 years, many of which have made great strides in reducing ambient levels of ozone by complying with existing regulations. It is easy to check whether adverse outcomes, from mortality rates to asthma rates, have decreased more where ozone levels have been reduced more. They have not. Even relatively large reductions in ozone, by 20% or more, have not been found to cause detectable reductions in deaths and illnesses from cardiovascular and respiratory illnesses, contrary to the EPA’s model-based predictions.
How the EPA and society proceed when confronted with a divergence between optimistic model-based predictions and practical reality will say much about what role, if any, we collectively want science and objective analysis to play in shaping crucial environmental and public-health regulations.
The cynical use of asthma patients to promote a pro-regulation political agenda that won’t actually help them undermines the credibility of regulatory science and damages the public interest.
Mr. Cox is the editor in chief of the peer-reviewed journal Risk Analysis and on the faculty of the University of Colorado School of Public Health. His Denver-based company, Cox Associates, develops and applies causal analyses for improving health outcomes.