Decision in EPA Case: As Flawed As the Analysis It’s Based On
On Tuesday, September 23, 2024, Judge Edward M. Chen of the US District Court for the Northern District of California ruled that the Environmental Protection Agency (EPA) must issue new rules related to fluoride levels in tap water.
The court wrote that “this finding does not conclude with certainty that fluoridated water is injurious to public health,” but it found that the plaintiffs had adequately demonstrated an “unreasonable risk” of harm.
This assertion is deeply concerning, for many reasons.
Reliance on a Troubled Report
The lawsuit, brought in April of 2017, took over seven years to conclude, a period that included waiting four years for the recently released NTP Monograph on the State of the Science Concerning Fluoride Exposure and Neurodevelopment and Cognition: A Systematic Review. This is the report that twice failed peer review by the National Academies of Science, Engineering and Medicine (NASEM), required additional scientific review by an NTP Board of Scientific Counselors (BSC), and which underwent a significant number of revisions and edits before it was finally released on August 21, 2024.
In concluding its two peer reviews, NASEM cautioned that the NTP “should make it clear that the monograph cannot be used to draw any conclusions regarding low fluoride exposure concentrations, including those typically associated with drinking-water fluoridation.” Why? The monograph’s conclusions applied to water that contained >1.5 mg/L of fluoride — more than twice the amount used to fluoridate water in the U.S.
Legal versus Scientific Expertise
To reach his opinion, the court drew heavily on the widely criticized monograph. In fact, the court did so despite explicit declarations by the NTP that its document was not designed to evaluate a potential risk of harm from drinking water containing fluoride at the optimal US level of 0.7 mg/L.
Experts from around the world have reviewed the same body of research and continue to find that the data support the safety of fluoride in water at recommended levels. While some studies suggest an association between high fluoride exposure and cognitive development, other analyses, some quite recent, show no such association. Organizations that follow the published research carefully, including the American Academy of Pediatrics, the American Academy of Pediatric Dentistry, the American Dental Association, the American Association for Dental, Oral, and Craniofacial Research, and many respected health authorities, continue to attest to and support community water fluoridation and fluoride use to prevent tooth decay.
Inconsistent Findings
Studies on fluoride exposure and neurodevelopment have yielded inconsistent findings, as reported in several recent research reviews. Analyses of data from Australia, Denmark, New Zealand, Spain, and Sweden have revealed no association between fluoride and cognitive deficits.
- In 2021, a study from Spain found that mothers’ prenatal fluoride exposure was associated with higher cognitive scores in boys at age 4, not lower. There was no difference in girls’ IQ.
- A large 2022 study in Australia determined fluoride exposure of boys and girls from birth to age 5, then their emotional / behavioral development was assessed through age 18. Exposure to fluoridated water in the first 5 years was not associated with altered measures of child emotional / behavioral development or executive function.
Confounding Factors
Finally, there are many confounding factors that affect IQ and measuring it, especially in children. Socioeconomic, physical, familial, cultural, genetic, nutritional, and environmental factors are all possible confounders. There has been only one fluoride-IQ study that followed people over a significant period of the lifespan. Published in 2020, this study tested the IQ of people in New Zealand at multiple ages to determine if a link existed. That 30-year study found no link between fluoride and IQ scores.
“There is nothing about the current decision that changes my confidence in the safety of optimally fluoridated water in the U.S.,” said Dr Charlotte Lewis. “Water fluoridation is a public health policy based on a solid foundation of evidence. When new research is published, health experts scrutinize it to make sure it meets high standards for public safety. That’s how it works.”
Dental disease in children continues to be the most common chronic disease, and it has significant effects on a child’s overall health and success.
Based on an enormous body of research and decades of experience, the American Academy of Pediatrics continues to support the use of fluoride and fluoridated drinking water to prevent tooth decay.
