Troubled Government Report Finally Sees the Light of Day

Posted August 27, 2024 & filed under Facts about Fluoride, Fluoride and Public Health, Fluoride in the News.

On August 21, 2024, the National Toxicology Program (NTP) posted the NTP Monograph on the State of the Science Concerning Fluoride Exposure and Neurodevelopment and Cognition: A Systematic Review on its website and concluded “with a moderate degree of confidence” that higher estimated exposure to fluoride is associated with lower IQ in children. The NTP defined this higher exposure as a level of more than 1.5 milligram per liter of fluoride in drinking water. This is double the level used for water fluoridation.

While this report does not evaluate or apply to community water fluoridation (CWF) in the United States, health providers and public health advocates are very concerned about information being taken out of context, undermining public trust and causing unwarranted alarm among pregnant women and parents.

Two Drafts, Two Reviews, Two Rejections

For more than four years, scientists, researchers and health professionals have been following the review and release of this troubled report. The National Academies of Science, Engineering and Medicine (NASEM) conducted peer reviews of the first two drafts (2019 and 2020) and twice rejected them, providing lengthy and detailed lists of “deficiencies” in the work. NASEM wrote that the NTP had not identified “clear and convincing” evidence to support its then-claim that “fluoride is presumed to be a cognitive neurodevelopmental hazard to humans” and suggested “further analysis or reanalysis”. The claim of a “presumed neurotoxin” was removed from the final report.

In delivering comments following its second review, NASEM directed the NTP to “make it clear that the monograph cannot be used to draw any conclusions” about low fluoride exposures, including the levels of exposure from community water fluoridation (CWF).

Publication Again Delayed

Publication of a revised version of the report was scheduled for May 22, 2022, but was abruptly canceled over ongoing concerns about research methods and conclusions. Two more years of review by an NTP Board of Scientific Advisors Working Group, which recommended an additional 93 edits and revisions, has resulted in a report from which the meta-analysis has been removed and submitted for publication elsewhere. NTP also removed its “hazard” designation of fluoride from the report.

Report’s Current Conclusions

The current version of the report concludes “with a moderate degree of confidence” that 1) exposure to fluoride at/above the level of ≥1.5 mg/L is “consistently associated with lower IQ in children” and 2) “more research is needed on the effects of fluoride exposure at levels below 1.5mg/L.”

The Report’s Conclusions in Context

The American Academy of Pediatrics (AAP) welcomes new research and will continue to issue recommendations on the use of fluoride based on expert review of the available evidence in conjunction with recommendations from public health authorities. Fluoride remains a very important component of ensuring optimal child oral and overall health.

• The NTP Monograph is a meta-analysis, not a research study. It examines associations and does not constitute research that demonstrates causation.
• The report’s conclusions are not applicable to U.S. fluoride levels. The optimal level of fluoride recommended for U.S. water supplies is 0.7mg/L, less than half the level considered by the report.
• 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. In addition, it is unclear whether data on children’s IQ extracted from a variety of different studies are accurate, comparable, or generalizable.
• Several recent reviews contradict NTP’s conclusions but were not included in its analyses. Research on fluoride exposure and neurodevelopment is widely heterogenous and to date has yielded inconsistent results.
• Tooth decay is the most common chronic disease for children and adults, and it creates a disproportionate burden on children with special health care needs, from families with low incomes, and people of color. Fluoride has been proven to prevent and reduce dental disease, and community water fluoridation is both efficient and effective at delivering primary prevention equitably to people of all ages who are served by fluoridated water systems.

Our experts agree. “While additional research to better understand the association and potential biologic mechanisms would be important, there’s nothing about the research that makes me concerned (about) … low levels of fluoride through use of toothpaste and drinking fluoridated water,” said Charlotte W. Lewis, M.D., M.P.H., FAAP, a member of the AAP Section on Oral Health.