Trump EPA Crosses Important Threshold on Science Policy Reform; Greens Get Political


News coverage would make most people think that Trump administration officials are doing everything possible to undermine environmental protection and human health. One article even goes so far as to suggest that “Trump EPA appointees want more air pollution,” which is just a ridiculous political attack.

It seems that the greens and the left-of-center press have never seen a regulation they didn’t like, because it grants the government more power, plain and simple. And anyone who disagrees with their approach is dubbed a “polluter.”

In reality, ongoing Environmental Protection Agency reforms offer the potential to improve public policy and help curb regulatory excesses, which is a good thing for consumers and businesses. After all, shouldn’t regulations actually produce benefits rather than simply impose needless costs to society?

For example, EPA Administrator Andrew Wheeler has solicited input from the agency’s Science Advisory Board (SAB) on ways to improve the agency’s cancer risk assessment guidelines—an effort that is long overdue. The SAB will hold a public hearing on the topic June 5 to launch this reform effort.

Activists fear that such reforms will overturn agency default assumptions about chemical risks that enable EPA to impose unwarranted, onerous regulations. The current guidelines are biased in favor of the assumption that chemicals pose health risks at any level of exposure, an approach known as the “linear-no-threshold model.” This assumption enables the agency to impose extremely stringent regulations on chemical use, even when exposures are so low they pose no measurable risk.

The March 2019 edition of Chemico-Biological Interactions provides a superb critique of the linear-no-threshold model, dedicating the entire issue to the topic. These articles point to a strong body of science that a “threshold-model” is much more likely in most cases.

The threshold model holds that a chemical may be safe below a certain exposure level—referred to as the threshold—yet pose risks of cancer or other health effects when exposure exceeds that threshold level. The concept is basically summed up as: “It’s the dose that makes the poison.” The threshold model helps explain why an element such as magnesium can be an essential dietary nutrient when consumed in small amounts and a deadly toxin at high exposures.

In some cases, low-level exposures of some chemicals are even beneficial, while high exposures are dangerous, which is the basis for a scientific concept known as hormesis. For example, Bobby R. Scotta and Sujeenthar Tharmal detail in Chemico-Biological Interactions how low exposures to radiation can reduce cancer risks, even though higher exposures can cause cancer. The human body responds to such low-level exposures by building defense mechanisms against cancer, enabling the body to better defend itself and thereby reduce cancer risks. The human body’s ability to develop such protective mechanisms is part of our evolutionary development.

In another article, researchers David Costantini and Benny Borremans demonstrate that the linear no-threshold model is “biologically unrealistic compared to threshold and hormetic models.” If it were correct, they argue “the evolution of life on Earth would not have been possible.”

Still, critics maintain that attempts by the Trump EPA to allow anything other than the linear-no-threshold model are dangerous and outside mainstream scientific thinking. One critic notes in The Conversation, for example, that the threshold model represents “an outlying view in science that is not consistent with views of independent experts,” and it basically amounts to “[a]ttacking regulation by attacking science.”

But such claims are utterly absurd. Advancements in science indicate that EPA’s reliance on the linear-no-threshold model is not only misguided, it has been contrary to the best science since the day it was imposed.

Toxicologists Edward Calabrese and Robert Golden provide an excellent historical overview in the Chemico-Biological Interactions issue as well. They explain how the linear-no-threshold model became embedded at EPA during the 1970s and why that was wrong from the get-go. In fact, Calabrese documents “a disturbing effort by some leaders of the radiation genetics community of the 1940s-1960s to force the acceptance of the LNT model, at almost any cost.” And he discusses “the well-documented evidence of deceptions, obfuscations, and deliberate scientific misconduct, all of which significantly affected the broader scientific and medical communities, and regulatory agencies of the U.S., such as EPA, and worldwide.”

Richard Williams’ article in Chemico-Biological Interactions details how EPA’s reliance on the linear model has produced regulations that cost billions of dollars without returning any measurable benefits. He notes:

EPA’s present LNT-driven program to mitigate indoor air radon to prevent lung cancer from homes and buildings costs billions of dollars each year while the benefits of the program are, at best, negligible. EPA’s program to reduce exposure from formaldehyde in composite wood products costs about $60 million each year, again, with negligible (or zero) benefits. Both programs demonstrate that the economic threshold for decreasing exposure has, for the most part, already been attained and would have been correctly identified if a threshold model had been employed. Thus, use of a threshold model, instead of an LNT model, would have resulted in a different policy.

If environmental activists and left-of-center media are really interested in protecting public health and the environment, they would support application of the best science, and that means eliminating reliance on faulty default assumptions about risk.

Let’s hope EPA’s Science Advisory Board plays the role it’s supposed to play—placing hard science above political science—by working with Wheeler and other EPA officials to facilitate a risk assessment process that applies the most relevant and best quality science.