Fluoride: Assessment for Developmental Neurotoxicity

The National Toxicology Program (NTP) conducted a systematic review to assess scientific studies on fluoride exposure and potential neurodevelopmental and cognitive health effects in humans. The report underwent two peer reviews by the National Academies of Science, Engineering, and Medicine (NASEM). Both times, the NASEM committee stated that NTP had not adequately supported its conclusions that fluoride should be classified as a cognitive neurodevelopmental hazard for humans.

Based on the NASEM review, the NTP removed the hazard classification of fluoride and made additional changes, resulting in two draft documents, 1) an NTP Monograph on the State of the Science that considered research published through May 2020, and 2) a manuscript on the meta-analysis of the data that considered research published through November 2021.

In May 2022, NTP Director Rick Woychik, Ph.D., decided to delay publication of the monograph and tasked the NTP Board of Scientific Counselors (BSC) to conduct a scientific review of the monograph, along with the meta-analysis. A BSC working group is currently reviewing the input from the NASEM committee, federal agencies, and external experts about the scientific strength of the NTP fluoride report and analysis and will provide a report for the BSC’s consideration at a forthcoming public meeting.

On March 15, 2023, the NTP added to this webpage the documents provided to the NTP BSC and working group for review including:

• A September 2022 working draft of the fluoride monograph that includes the NTP’s responses to a significant number of substantive comments and criticisms of the May 2022 draft received from federal subject matter experts at the CDC, FDA, and NIH.
• A July 2022 working draft of the meta-analysis manuscript on fluoride that notes NTP’s response to each of many comments and criticisms received from federal subject matter experts at the CDC, FDA, and NIH.
• The May 2022 draft of the NTP fluoride monograph, which was slated for publication, but withheld for further scientific review based on the comments and criticisms raised.
• Other background materials.

The BSC Working Group is expected to report its evaluation to the BSC at a public meeting on May 4, 2023. In turn, the BSC will make a recommendation to Dr. Woychik, and he will make the decision about publication and dissemination of the NTP Fluoride Monograph and submission of the meta-analysis manuscript to a journal.

Supplemental materials for some events, meetings, and workshops prior to 2020 have been archived. These archived materials frequently include presentations, background materials, and public comments. Email us or use our contact form to request a list or copy of archived materials.