The EPA’s flawed zero tolerance policy

Kathleen Hartnett White Senior Fellow, Texas Public Policy Foundation
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For the last three years, the Environmental Protection Agency has justified new air quality regulations — unprecedented in stringency and cost — on the assumption that even trace levels of particulate matter can cause early death.

A recent EPA report states that by 2020, the EPA’s rules “will prevent 230,000 early deaths.” EPA Administrator Lisa Jackson has gone so far as to testify before Congress that the new regulations would provide health benefits as valuable as a cure for cancer. If true, this is compelling. Unfortunately, such rhetoric is built on implausible assumptions, biased models, statistical manipulations and two cherry-picked studies.

Unwinding this tangled web is tedious but necessary to prevent the EPA from becoming a national economic planning agency that transforms our economy and undermines our form of democratic government, in which elected representatives — not federal technocrats — have the authority to make the country’s major policy decisions.

On Wednesday, a U.S. House subcommittee will conduct a hearing to examine the real costs and benefits of the EPA’s environmental regulations, with invited testimony from one of my former colleagues at the Texas Commission on Environmental Quality.

As I noted in my latest report for the Texas Public Policy Foundation, “EPA’s Pretense of Science,” the EPA now justifies almost every major new air quality rule on the basis of models indicating implausibly exaggerated health risks from fine particulate matter, rarely considered a killer by physicians or toxicologists.

Extrapolating from assumptions, the EPA in 2009 decided that no risk is too low, improbable or uncertain that it is not worth responding to with regulation. With a straight face, the EPA’s leadership now maintains that there is no safe level of ambient fine particulate matter — however near to zero — at which risk of “early” death ceases. Statisticians call this analytic approach a “no threshold linear regression to zero.”

The Clean Air Act requires that national air quality standards be set at levels adequate to protect human health with a margin of safety and regardless of cost. That’s a very cautious rubric. But through the no-safe-threshold assumption, the current EPA goes further: to zero risk. This methodological change leads the EPA to the implausible finding that mortal risks increase to the extent that ambient levels of fine particulates exceed natural background levels of 1 microgram per cubic meter. The current federal standard is 15 micrograms per cubic meter.

Gina McCarthy, the EPA’s assistant administrator for air, defended the no-safe-threshold approach in a recent letter to Congress: “These studies have not observed a level below which premature mortality effects do not occur. … There is no threshold level of fine particle pollution below which health risk reductions are not achieved by reduced exposure.”

While the EPA’s defense begs the question, it revealingly states the obvious: The point at which risk falls to zero cannot be proven. This is certainly true when it comes to human mortality.

Indoor levels of fine particulates are far higher than outside levels. Cleaning a closet, cooking, cruising through a mall — any takers that these activities carry risk of premature death? In fact, the EPA’s obsession with fine particulates is at odds with health-effects studies across multiple disciplines. Moreover, the agency largely ignores toxicological studies that actually evaluate the impact of outdoor concentrations of fine particulates on cardiopulmonary function. Most toxicological data shows that current levels of airborne fine particulates are too low to cause disease or death.

If the EPA is so convinced that trace levels of particulate matter present dire health risks, the agency should make a case for strengthening the national standard, as the Clean Air Act requires. The fact that the EPA apparently is not considering lowering the current fine particulate standard to one or two micrograms suggests that the agency doesn’t lend that much credence to the no-threshold approach used to justify other regulations.

Despite what you may have heard, the human mortality rate is still holding steady at 100 percent, although life expectancy has increased by 70 percent over the last century.

Environmental standards should reflect a societal judgment about unacceptable risk. The current EPA’s dalliance with the no-safe-threshold assumption to conjure over 200,000 statistical lives now at risk of death is a misuse of science and a disservice to the public.

Kathleen Hartnett White is senior fellow and director of the Armstrong Center for Energy and Environment at the Texas Public Policy Foundation. She was commissioner and chairman of the Texas Commission on Environmental Quality from 2001 to 2007.