When I worked for the Environmental Protection Agency in the 2010s as an Obama administration appointee, I helped write and review dozens of regulations under the Clean Air Act. They included some groundbreaking rules, such as setting national air quality standards for ozone and fine particulate matter.

For each rule, we considered the costs to industry if the rule went into effect – and also the benefits to people’s health.

Study after study had demonstrated that being exposed to increased air pollution leads to more asthma attacks, more cardiovascular disease and people dying sooner than they would have otherwise. The flip side is obvious: Lower air pollution means fewer asthma attacks, fewer heart problems and longer lives.

To use this information in making decisions, we needed to have a way to compare the costs of additional pollution controls to industry, and ultimately, to consumers, against the benefits to public health. A balanced approach meant putting a dollar value on health benefits and weighing them against the seemingly more easily, though not always accurately, predicted costs of complying with the regulations.

We were able to make these decisions because environmental economists since the 1980s have developed and continually improved robust methodologies to quantify the costs to society of air pollution’s effect on human health, such as workdays lost and hospital visits.

Now, however, the Trump administration is dropping one whole side of that cost-benefit equation. The EPA wrote in January 2026 that it will stop quantifying the health benefits when assessing the monetary impact of new pollution regulations and regulation changes involving pollutants that contribute to ozone, or smog, and fine particulate matter, known as PM2.5.

The result leaves government decision-makers without a way........

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