Guest Opinion

Fluorine is the most reactive element on the periodic table, and it has also generated strong reactions in public opinion.

Fluoride, an ionic form of fluorine, has been the subject of controversy and conspiracy theories because of the federal requirement to add it to public drinking water systems. Secretary of the Department of Health and Human Services Robert Kennedy has said, “Fluoride is an industrial waste associated with arthritis, bone fractures, bone cancer, IQ loss, neurodevelopmental disorders, and thyroid disease.” Several states have begun taking action on their own without waiting for the federal government to act. Both Florida and Utah have passed state laws restricting its use. Nebraska and Louisiana proposed legislation in 2024–25 that passed in one legislative chamber but failed in the other. Arkansas, Kentucky, and Tennessee all saw bills introduced that either died in committee or were not acted upon before the end of the legislative session.

Fluoride does not kill bacteria like chlorine, another chemical added to public water systems, but it contributes to bone and tooth growth and maintenance. Advertisements for toothpaste have long told us that fluoride prevents cavities. In a recent report from the National Institutes of Health’s Department of Toxicology, researchers comprehensively examined the toxicological effects of fluoride. They followed a cohort of more than 10,000 people to age 80 and determined that fluoride did not have negative effects on intelligence, despite the interpretation given to that report by those opposed to adding fluoride to water systems. It is true, however, that the founder of the field of toxicology is often quoted as saying, “The dose makes the poison.”

Recent Litigation

Interest groups seeking to limit fluoride in public drinking water systems petitioned the Environmental Protection Agency (EPA) to regulate fluoride under the Toxic Substances Control Act (TSCA). The EPA is petitioned regularly to regulate substances or take other actions as part of the administrative regulatory process. The agency may ignore those petitions or act on them if doing so falls within its statutory authority.

The EPA declined to regulate fluoride, and when that decision was reviewed by a U.S. District Court, the court concluded that the agency had not adequately considered newer research and ordered a new trial to examine it.

In May 2026, the U.S. Court of Appeals for the Ninth Circuit vacated the district court’s decision and remanded the case, finding an abuse of discretion. The appellate court determined that the district court had effectively commandeered the case after the first bench trial by going beyond the issues presented by the parties. When the district court ordered a new bench trial on facts neither party had requested, the appeals court found that it had violated the principle of party presentation.

This is also a story about why courts should not be responsible for analyzing scientific studies that may form the basis of future regulations. In this case, the court wanted the EPA to consider a 2025 meta-analysis. Such studies examine all available research on a subject—in this instance, the risks of fluoride—and draw conclusions based on the collective findings. This approach can be problematic because the methodology and quality of individual studies often vary significantly, which can lead to unreliable conclusions.

A good example of the limitations of meta-analysis comes from the EPA’s study of electromagnetic fields (EMF) from high-voltage power lines in 1987. I was serving in the Office of Science and Technology Policy as a Senior Environmental Analyst and was one of the reviewers. The report was a meta-analysis of approximately two dozen studies, most of which were inconclusive. However, because many suggested the possibility of a connection between cancer and proximity to power lines, the meta-analysis concluded that EMF exposure from power lines must cause cancer. A collection of uncertain conclusions cannot logically produce a certain conclusion, and that was one of the report’s central flaws.

All of this is to say that meta-analyses can be useful in identifying areas requiring additional study, but they can also be misleading if not carefully evaluated. The court had directed the EPA to consider such a study in determining whether fluoride poses an unreasonable risk in drinking water.

Adding Fluoride to Public Drinking Water

The U.S. Public Health Service first recommended adding fluoride to public water systems in 1962.

Some regions naturally contain high levels of fluoride in groundwater. Texas, Oklahoma, New Mexico, Arizona, and Colorado, particularly in the arid Southwest and southern Great Plains, experience elevated fluoride concentrations because fluoride leaches from volcanic and granitic rock and accumulates in slow-moving groundwater. This region consistently records the highest fluoride levels in the country and reflects a broader global pattern. Elevated naturally occurring fluoride concentrations in groundwater, exceeding 1.5 mg/L, are common throughout western North America and other high-fluoride regions around the world. More localized pockets of elevated fluoride occur in South Carolina, Virginia, and parts of the Upper Midwest.

Water systems that add fluoride serve approximately 67 percent of the U.S. population. Among nearly 8 billion person-months of data from fluoridated water systems between 2016 and 2021, only 0.01 percent exceeded the EPA’s 2.0 mg/L secondary standard. A standard set at 1.5 mg/L would primarily require treatment in areas with naturally high fluoride levels through defluoridation rather than ending community fluoridation programs. By contrast, reducing the allowable level well below 0.7 mg/L would be the threshold that would significantly curtail the practice of adding fluoride to public water systems.

Final Thoughts

General background levels of fluoride make standard-setting difficult because the Safe Drinking Water Act does not require the reduction of naturally occurring background contaminants. Instead, it requires disclosure of those contaminants to the public. If fluoride were regulated under TSCA as a toxic pollutant, however, defluoridation would be required in areas with naturally elevated fluoride concentrations.

The benefits of fluoridation would need to be weighed against its risks, and at present, scientific studies remain inconclusive regarding many of fluoride’s long-term effects. A recommended standard of 1.5 mg/L would primarily affect areas with naturally high fluoride levels, whereas a standard of 0.7 mg/L would be necessary to begin significantly reducing existing fluoridation practices in public water systems.

The cost of reducing contaminants increases exponentially with each additional increment of reduction, meaning that stricter standards can become very expensive very quickly. In the meantime, while additional research is conducted, a standard of 2.0 mg/L would be a reasonable starting point, particularly since only 0.01 percent of systems currently exceed that level. Such an approach would establish a measurable safety benchmark, allow for continued study of fluoride’s effects, and minimize financial impacts on public water systems while still providing a margin of public health protection.

To read more articles by Professor Sutton go to:  https://profvictoria.substack.com/ 

Professor Victoria Sutton (Lumbee) is a law professor on the faculty of Texas Tech University. In 2005, Sutton became a founding member of the National Congress of American Indians, Policy Advisory Board to the NCAI Policy Center, positioning the Native American community to act and lead on policy issues affecting Indigenous communities in the United States.