Andreas Schuld
In 2015, upon a nomination from the Fluoride Action Network (FAN), the United States National Toxicology Program (NTP) set out to conduct a systematic review of the scientific research on fluoride exposure and neurodevelopmental and cognitive health effects in humans. The review was intended to evaluate human studies, experimental animal studies, and mechanistic data.[1]
In 2019, NTP’s findings were presented in the first draft monograph entitled “Systematic Review of Fluoride Exposure and Neurodevelopmental and Cognitive Health Effects.” The NTP concluded that “fluoride is presumed to be a cognitive neurodevelopmental hazard to humans.”[2]
The NTP then asked the National Academies of Science, Engineering, and Medicine (NASEM) to review the draft monograph.
NASEM published its review in 2020, pointing out many flaws and inconsistencies, concluding that the NTP had not adequately supported its conclusion.[3] NASEM emphasized that the review committee’s findings did not mean that NTP’s conclusions were incorrect. Instead, it stressed the necessity for additional analysis or a re-evaluation to support those conclusions.
In response to the committee’s recommendations, NTP proceeded to revise the initial monograph.[4] The revised monograph was then again presented to NASEM for further review.
In 2021, NASEM published its review, again concluding that the NTP had not adequately supported its conclusions that fluoride should be classified as a cognitive neurodevelopmental hazard for humans.[5]
Following this second NASEM review, NTP eliminated the hazard classification of fluoride and decided to downgrade the fluoride monograph from a systematic review to a “State of the Science” document instead. This led to the creation of two distinct draft documents:
1) a NTP Monograph on the State of the Science, encompassing research up to May 2020, and
2) a manuscript focusing on the meta-analysis of data, considering research up to November 2021.
This time, the NTP did not submit the revision to NASEM for further review, but instead asked five peer reviewers to evaluate the documents.
Following the peer review, the two NTP documents were finally slated to be published in May 2022. However, allegedly, efforts were made by the National Institutes of Health, the Centers for Disease Control and Prevention, and others, to thwart their release.
In May 2022, NTP Director Richard Woychik opted to postpone the release of the monograph.
In June 2022, Dr. Woychik assigned the NTP Board of Scientific Counselors (BSC) the responsibility of conducting a scientific assessment of NTP’s handling of 325 comments and critiques from external peer reviewers and federal agency experts regarding the monograph. Additionally, the BSC had previously been assigned the task of reviewing NTP’s responses to 141 comments related to the meta-analysis manuscript. To aid in the scientific review, a Working Group within the BSC was convened. The group started its work on October 2022.
In March 2023, as part of an agreement under the ongoing Toxic Substances & Control Act (TSCA) lawsuit against the Environmental Protection Agency (EPA) on fluoride’s neurotoxicity, the NTP released all documents that had been provided to the BSC.[6]
On May 4, 2023, the BSC Working Group presented its report to the BSC, recommending 93 revisions to the monograph and 81 revisions to the meta-analysis manuscript, primarily addressing scientific issues, data insufficiencies, and clarity.
The BSC accepted the report with the condition of verifying an IQ statistic. The Working Group made the correction, and on May 16, 2023, the BSC approved the report, submitting it to Dr. Woychik for his consideration and final decision on publishing the NTP Monograph and meta-analysis manuscript.[7]
To this date, the documents have not been published.
PFPC Involvement
Our group, the Parents of Fluoride-Poisoned Children (PFPC) has been active in fluoride education for over 25 years. Our group was formed when we became aware that the adverse health effects we observed in our children were largely identical to those reported by others as being due to thyroid dysfunction. Our research led us to the discovery of over 650 international studies on fluoride effects on iodine metabolism and thyroid dysfunction.[8] With the help of fluoride researchers, historians, and international libraries, we were able to obtain many studies documenting the use of fluoride compounds in the treatment of iodine-induced hyperthyroidism. We also learned that most of the research linking fluoride to thyroid dysfunction had been actively suppressed by public health agencies worldwide, including the World Health Organization (WHO), the European Scientific Committee on Health and Environmental Risks (SCHER), as well as the U.S. CDC, the Agency for Toxic Substances and Disease Registry (ATSDR), the NTP, and the EPA.
Shortly after we became aware of the 2015 NTP call for public comments on the fluoride nomination via an announcement made in the US Federal Register, we made a submission to the NTP, supporting the effort.[9] As thyroid hormones are essential for neurodevelopment, and “mechanistic data” was to be considered, our hopes were high that this review would include the studies linking fluoride to thyroid dysfunction. Over 200 papers on fluoride effects on thyroid hormone metabolism had been published in the last 20 years in China alone, a country greatly afflicted with both fluoride poisoning and iodine deficiency/excess disorders.[8]
Reading the background papers provided by the NTP, we realized that once again, past reviews were being cited and relied upon that had not only withheld most of the research on fluoride effects on thyroid hormone metabolism, but also falsified results of the few studies that did get mentioned. In our submission to the NTP, we highlighted some of these disturbing examples of scientific misconduct, providing specific examples. In addition, we offered our database of Chinese studies and essential information on how fluoride metabolism differed in humans and rodents, the latter being an issue that was consistently misunderstood.[9]
The NTP had promised transparency and announced that all submissions would be posted on their website. However, a few months later we realized that the hyperlink to our submission, while being listed on the website, had been removed, and thus our submission was no longer accessible to anyone.[10] At this point we grew suspicious and felt our hopes diminishing. We had been involved in numerous fluoride reviews since the late 1990s, including the 1999 York Cochrane Review and the 2006 review by the NRC, and had learned to heed the early warning signs.
In July 2016, the NTP published its first document, a peer-reviewed systematic review of the animal evidence on the effects of fluoride on learning and memory.[11] When we first read it, we could not believe both the incompetence and also the deliberate intent to mislead. Sometimes milligrams were confused with micromoles, observed differences in fluoride metabolism between humans and rodents were distorted and dismissed – “assuming approximate equivalence is not unreasonable” and—wait for it—thyroid studies had been excluded – because they “were considered beyond the scope of this review.”
Digging a little deeper, we learned that the actual work on this review was done by ICF International, a huge multi-national consulting firm that, for many decades, has made billions in profits from government contracts, especially around clean-ups and environmental assessments of heavily contaminated US Superfund sites.
In 2016, ICF was awarded a $60 million task order by the National Institute of Environmental Health Sciences (NIEHS) to provide “Scientific Information Management and Literature-Based Evaluation Support” to the NTP.[12] Sixteen ICF scientists worked on the animal literature review, while over 60 ICF scientists worked on the NTP fluoride monograph draft.
We first became aware of ICF in the 1990s, after learning that the 1993 “ATSDR Toxicological Profile on Fluoride, Hydrogen Fluoride, and Fluorine” had been authored by Clement International Corporation,[14] then a subsidiary of ICF Kaiser, as ICF was called then. At the time, we found it extremely disturbing that a company that was actively involved in the aluminum industry, consulting aluminum companies like ALCOA and constructing smelters, was allowed to write a profile on one the most prevalent pollutants from said industry (one tonne of aluminum produces 15 kg of fluoride).[15]
As one might expect, that ATSDR profile mentioned only ONE (!) rodent study that dealt with fluoride effects on thyroid hormone metabolism and further misrepresented its findings. Many studies had been available, some even included in the profile’s own literature list, but findings were not included nor discussed. A paper by Donald Hillman and colleagues from the Michigan State University, entitled “Hypothyroidism and anemia related to fluoride in dairy cattle”[16] was discussed several times in the profile, but only as it related to the findings on anemia—the effects on thyroid hormones were excluded entirely.
To understand the implications of this, the reader needs to know that US ATSDR Toxicological Profiles are mandated by Congress to provide information on hazardous substances commonly found at National Priorities List (Superfund) sites. They must “characterize succinctly the toxicological and adverse health effects information for the hazardous substance being described,” so that health care providers treating patients potentially exposed to such hazardous substances will know what to look for.[17]
If vital information is withheld from agencies mandated to disseminate this information to healthcare practitioners, how will the practitioners ever learn about fluoride poisoning?
Back to the NTP documents.
When NASEM announced a public meeting and provided a forum for public comments following the first revision, we made another submission, this time to NASEM. We showed how the NTP had misrepresented the scientific results of some of the fluoride/thyroid studies, addressed the unjustified exclusion of animal studies, the 20 ppm fluoride/water concentration as a cut-off for ALL animal studies, and alerted to various other important issues.[18]
None of the errors were corrected by the NTP, and NASEM did not address any of our concerns in their second review.
Where Are We Now?
Shortly after the BSC submitted its final report to the NTP Director, we wrote an extensive letter to Dr. Woychik, asking for postponement of publication, so that critical flaws could be corrected.[19] You will find this letter reproduced in this edition of the Townsend e-Letter.
Dr. Woychik replied, thanked us for the letter, and informed that he had shared the letter with staff, “so that they can consider your input on the importance of iodine status as a confounder/effect modifier of the effects of fluoride.” [20]
Meanwhile, anti-fluoridation groups have fully supported the NTP drafts as being the “best science”, and experts engaged by FAN in their TSCA lawsuit against the EPA have cited the NTP drafts in new studies as if they were final published reports – which they are not [21]. In the past, these experts have also published their own reviews on this matter, committing the same errors as the NTP. Completely ignoring the literature on the fluoride-iodine antagonism, attempts are made to set benchmark concentration levels, which is patently absurd if iodine/thyroid status is not considered.[21] If there is iodine deficiency present, even small fluoride amounts will greatly further decrease IQ loss,[22] while in iodine excess conditions, low fluoride intake may show an increase in IQ until a certain threshold is reached, after which the opposite effect is seen.[23, 24]
Pro-fluoridation groups, on the other hand, firmly opposed the NTP conclusions and continue to deny the effects of fluoride on thyroid hormone metabolism at current intake estimates, despite hundreds of studies documenting it.
In the US, it is estimated that 70% of the children and adolescents now have dental fluorosis (mottled teeth), the visible sign of fluoride over-exposure during development.[26]
It is high time that this issue is evaluated with a balanced and scientific approach. The impact of fluoride on thyroid health is a complex matter that deserves a thorough examination, taking into account all available scientific evidence.
Our health depends on it.
References
[1] Federal Register Notice, October 7, 2015 https://poisonfluoride.com/dir/wp-content/uploads/FED-REG-ntp-nomination-oct_.7.2015.pdf
[2] National Toxicology Program – Draft NTP Monograph on the Systematic Review of Fluoride Exposure and Neurodevelopmental and Cognitive Health Effects https://poisonfluoride.com/dir/wp-content/uploads/draft_fluoride_monograph_20190906_5081.pdf
[3] National Academies of Sciences, Engineering, and Medicine; Division on Earth and Life Studies; Board on Environmental Studies and Toxicology – “Exposure and Neurodevelopmental and Cognitive Health Effects; Committee to Review the NTP Monograph on the Systematic Review of Fluoride. Review of the Draft NTP Monograph: Systematic Review of Fluoride Exposure and Neurodevelopmental and Cognitive Health Effects” Washington (DC): National Academies Press (US) (2020) https://www.ncbi.nlm.nih.gov/books/NBK555056/
[4] National Toxicology Program – Revised Draft Monograph on the Systematic Review of Fluoride Exposure and Neurodevelopmental and Cognitive Health Effects (2020) https://poisonfluoride.com/dir/wp-content/uploads/NTP-Revised-monograph-9-16-2020.pdf
[5] NASEM – Review of the Revised NTP Monograph on the Systematic Review of Fluoride Exposure and Neurodevelopmental and Cognitive Health Effects: A Letter Report (2021) https://www.nationalacademies.org/our-work/review-of-the-revised-ntp-monograph-on-fluoride-exposure-and-neurodevelopmental-and-cognitive-health-effects
[6] NTP – Documents Provided to the NTP Board of Scientific Counselors (BSC) and BSC Working Group https://ntp.niehs.nih.gov/sites/default/files/202303/documents_provided_bsc_wg_031523.pdf
[7] NTP Board of Scientific Counselors Working Group Report on the Draft State of the Science Monograph and the Draft Meta-Analysis Manuscript on Fluoride Final Report: Approved by the NTP Board of Scientific Counselors on May 16, 2023 https://ntp.niehs.nih.gov/sites/default/files/2023-05/BSC_WG_Report_Final_Version_BSC_approved051623_508.pdf
[8] PFPC – Fluoride Effects on Thyroid Hormone Metabolism: Recent Research (2023) https://poisonfluoride.com/phpBB3/viewtopic.php?f=7&t=1345
[9] PFPC Submission to NTP (2016) https://poisonfluoride.com/NTP-Jan-8-2016-PFPC-4.pdf
[10] PFPC Submission – Link Removal https://poisonfluoride.com/dir/wp-content/uploads/NTP_Link_removal.png
[11] National Toxicology Program – “NTP Research Report on Systematic Literature Review on the Effects of Fluoride on Learning and Memory in Animal Studies: Research Report 1 [Internet]. Research Triangle Park (NC): National Toxicology Program (2016) https://www.ncbi.nlm.nih.gov/books/NBK552739/
[12] ICF Awarded $60 Million Task Order by National Institute of Environmental Health Sciences – ICF to Provide Scientific Information Management and Literature-Based Evaluation Support to National Toxicology Program (June 2016) https://www.icf.com/news/2016/06/icf-awarded-niehs-task-order
[13] Greenwire – EPA hired consultants to counter staff experts on fluoride https://www.eenews.net/articles/epa-hired-consultants-to-counter-staff-experts-on-fluoride/
[14] Agency for Toxic Substances and Disease Registry; US Public Health Service; Clement International Corporation – “Toxicological Profile on Fluoride, Hydrogen Fluoride, and Fluorine” (1993) https://poisonfluoride.com/dir/wp-content/uploads/ATSDR-1993-edit.pdf
[15] ICF Press Release – ICF Kaiser Named Provider of Environmental Services to Alcoa (1997) https://poisonfluoride.com/dir/wp-content/uploads/ICF-Kaiser-Alcoa-1997-PR.png
[16] Hillman D, Bolenbaugh DL, Convey EM – “Hypothyroidism and anemia related to fluoride in dairy cattle” J Dairy Sci 62(3):416-23 (1979) https://www.journalofdairyscience.org/article/S0022-0302(79)83261-0/pdf
[17] ATSDR – Toxicological Profiles https://www.atsdr.cdc.gov/toxprofiledocs/index.html
[18] PFPC – Submission to NASEM (2020) https://poisonfluoride.com/dir/wp-content/uploads/PFPC-Comments-NASEM-Review-of-NTP-Revised-Monograph-Revised-Nov-14-2020.pdf
[19] PFPC – Letter to Richard Woychik, Director, NTP & NIEHS https://pfpc.substack.com/p/pfpc-letter-to-richard-woychik-director
[20] Richard Woychik – Response to PFPC Letter (2023) https://poisonfluoride.com/dir/wp-content/uploads/Response-to-May-25-letter-to-Dr.-Woychik_v2.pdf
[21] Grandjean P, Meddis A, Nielsen F, Beck IH, Bilenberg N, Goodman CV, Hu H, Till C, Budtz-Jørgensen E – “Dose dependence of prenatal fluoride exposure associations with cognitive performance at school age in three prospective studies” Eur J Public Health ckad170 (2023)
https://academic.oup.com/eurpub/advance-article/doi/10.1093/eurpub/ckad170/7291347
[22] Lin Fa-Fu, Aihaiti, Zhao Hong-Xin, Lin Jin, Jiang Ji-Yong, Maimaiti, and Aiken – “High-fluoride and Low-iodine Environment and Subclinical Cretinism in Xinjiang” Endemic Diseases Bulletin 6(2):62-67 (1991) English Translation (ICCIDD) – https://poisonfluoride.com/pfpc/lin-1991.pdf
[23] Ibarluzea J, Gallastegi M, Santa-Marina L, Jiménez Zabala A, Arranz E, Molinuevo A, Lopez-Espinosa MJ, Ballester F, Villanueva CM, Riano I, Sunyer J, Tardon A, Lertxundi A – “Prenatal exposure to fluoride and neuropsychological development in early childhood: 1-to 4 years old children” Environ Res. 112181 (2021) https://www.sciencedirect.com/science/article/pii/S0013935121014821
[24] Du Y, An N, Hu Y, Duan L, Ma J, Huang H, ZhuJ, Sun L, Li Z, Ba Y – “IQ Alterations in Children at 7-13 Years Old: The Roles of Prenatal and Childhood Fluoride Exposure” Conference Proceedings, The 8th International Conference on Medical Geology, Guiyang, China (2019)
NOTE: Iodine-excessive area – average UIC –> 396 ug/L
https://poisonfluoride.com/dir/wp-content/uploads/DU-ET-AL.-2019.pdf
[25] PFPC – “The American Fluoridation Society & Kheradpisheh, Singh and Peckham” (2021) https://poisonfluoride.com/phpBB3/viewtopic.php?f=91&t=3749
[26] Dong H, Yang X, Zhang S, Wang X, Guo C, Zhang X, Ma J, Niu P, Chen T – “Associations of low level of fluoride exposure with dental fluorosis among U.S. children and adolescents, NHANES 2015-2016” Ecotoxicol Environ Saf 221:112439 (2021) https://www.sciencedirect.com/science/article/pii/S0147651321005510
Published December 16, 2023
About the Author
Andreas Schuld is head of the organization Parents of Fluoride-Poisoned Children (PFPC), based in Vancouver, Canada. https://poisonfluoride.com/