National Academies ’strongly recommends’ third revision to fluoride monograph

Washington - The National Academies of Sciences, Engineering, and Medicine is strongly recommending that the National Toxicology Program revise its draft monograph to make clear that "much of the evidence presented comes from studies that involve relatively high fluoride concentrations" and that the monograph "cannot be used to draw conclusions about low fluoride exposure concentrations, including those typically associated with drinking-water fluoridation."

In a report released Feb. 9, the National Academies of Sciences, Engineering, and Medicine, or NASEM, said its committee tasked with reviewing the monograph, formally titled Systematic Review of Fluoride Exposure and Neurodevelopmental and Cognitive Health Effects, had several concerns. These included having difficulty following the National Toxicology Program's reported methods, identifying "worrisome" inconsistencies and not being able to find some key data used in the meta-analysis as well as having concerns regarding the wording of some conclusions.

"It is critical for the monograph to be able to withstand scientific scrutiny by those who have vastly different opinions on the risks and benefits associated with fluoride exposure given that the issue has become highly contentious," said NASEM in a news release summarizing the new report. "Therefore, the committee strongly recommends that NTP improve the revised monograph by implementing its suggestions to improve clarity and transparency."

Jayanth Kumar, D.D.S., a member of the National Fluoridation Advisory Committee, said the findings are good news for dentistry.

"The NASEM Committee advised the National Toxicology Program to make it clear that the NTP draft monograph cannot be used to draw any conclusions regarding low fluoride exposure concentrations, including those typically associated with drinking-water fluoridation," Dr. Kumar said. "The United States Public Health Service and almost all major health organizations have affirmed the safety of water fluoridation."

NASEM's concerns mirror those of the Association. In October 2020, the ADA filed comments ahead of the committee's review of the revised monograph, urging it to support the Association's request for the National Toxicology Program to change its classification of fluoride from presumed neurotoxin to no neurotoxic health effect at low levels. In the comments, the ADA also said that currently, there is not a wide body of scientific literature examining fluoride as a potential neurotoxin and said what is available is "either lacking, unreliable, inconclusive, conflicting or subject to widespread interpretation."

The Association also pointed to NTP's own acknowledgement that its claim of "presumed" neurotoxin is based on a "low-to-moderate level of evidence" and said that if NTP moves forward with this claim, it is critical to "clearly and consistently qualify" that "the claim applies only to abnormally high levels of fluoride exposure of more than 1.5 mg/L." Fluoridated drinking water in the U.S. is set at 0.7 mg/L.

This is not the first time that NASEM has asked NTP to revise its monograph.

In 2019, the National Toxicology Program released the first draft monograph, Systematic Review of Fluoride Exposure and Neurodevelopmental and Cognitive Health Effects, and requested NASEM to review. In response to that request, NASEM released, Review of the Draft NTP Monograph Systematic Review of Fluoride Exposure and Neurodevelopmental and Cognitive Health, that "identified deficiencies in the analysis of various aspects of some of the studies and in the analysis, summary, and presentation of the data in the draft monograph, provided many suggestions for improvement, and concluded that NTP had not adequately supported its conclusions," according to the report's summary .

The National Academies are private, nonprofit institutions that provide independent, objective analysis and advice to the nation to solve complex problems and inform public policy decisions related to science, technology and medicine.

"Fluoridation Facts" is among a number of free ADA resources on community water fluoridation, which the ADA has supported since 1950, according to the publication. Other resources are located online at ADA.org/fluoride.