Fluoride Action Network

Fluoridation Review #28

Fluoridation Review #28 • By Mike Dolan • October 30, 2023

Danish Cohort Data, When Combined With Mexican And Canadian Studies, Confirm Fluoride’s Neurotoxicity at Low Dose

The inclusion of research data from over 800 mother-child pairs in Odense, Denmark, when merged with data from comparable studies from Mexico and Canada, has led scientists to conclude that a level of just 0.45 milligrams of fluoride per liter (mg/l) of pregnant mother’s urine showed a statistically significant association between urine-fluoride and decreased child IQ. Generally, urine fluoride concentration is similar to the level of fluoride found in drinking water. The standard for fluoride added to drinking water supplies is 0.7 mg/l.

While the Odense cohort study did not find a statistically significant association between pregnant mother’s urine and child IQ at 7 years old, the authors discuss how the analysis could underestimate the fluoride association with the neurotoxicity outcome.

The Danish study did not find boys to be more vulnerable than girls, as had been found in the Canadian study.

The authors, writing in the European Journal of Public Health, report, “The combined data showed that an increase in maternal pregnancy urinary fluoride by 1 mg/l significantly predicted an IQ decrease by 2.06 points.”

They concluded that their findings have important public policy implications, writing, “Given the combined observations on more than 1500 mother–child pairs, the overall BMC [benchmark concentration] results likely reflect a threshold for adverse cognitive effects of prenatal fluoride exposure that occur at levels prevalent in many countries.”

“These findings support that fetal brain development is highly vulnerable to fluoride exposure,” they note.

The authors point out the limitation of the current internationally recommended maximum concentration, concluding, “The pooling of results from three prospective cohorts conducted in areas with wide ranges of overlapping exposure levels offers strong evidence of prenatal neurotoxicity, and these findings should inspire a revision of water-fluoride recommendations aimed at protecting pregnant women and young children. For example, the World Health Organization’s recommendation of 1.5 mg/l as an upper limit for fluoride in drinking water does not consider developmental neurotoxicity.”

Source: https://doi.org/10.1093/eurpub/ckad170

Relatively Low Fluoride in Drinking Water Increases Risk of Knee Osteoarthritis (KOA), According to New Chinese Study

A case-control study that matched water fluoridation and urinary fluoride levels with X-ray examinations of affected patients for over 1,110 residents of Heilongjiang province found that people exposed to levels of fluoride in water above 0.88 mg/L showed an increased risk of knee osteoarthritis (KOA) compared to people whose fluoride water level was below 0.248 mg/L.

The maximum level of fluoride contamination in drinking water allowed in China is 1.0 mg/L. In the USA, it is 4.0 mg/L, while 0.7 mg/L is deliberately added to many water supplies as part of fluoridation programs.

While the authors highlighted the strengths of their study, such as its large sample size and case-control design, they also noted that the primary source of exposure is community-derived water, but there may be some other sources of exposure (toothpaste, tea consumption, food), that may affect the assessment of the relationship between external fluoride exposure and osteoarthritis.

“Current standards do not take into account the effects of long-term fluoride exposure on cartilage and skeleton damage. However, many adults with water fluoridation intake close to the standard were at risk of osteoarthritis, notably the population with aged less than 60, male and obesity. As a result, the findings of our study can be seen as evidence the need to review current water fluoridation regulations,” conclude the authors from the Harbin Medical University in Environmental Geochemistry and Health September 16.

Source: https://doi.org/10.1007/s10653-023-01742-1

Community Water Fluoridation Correlated With Pediatric Fractures

Higher levels of community water fluoridation, as recorded by the Centers for Disease Control and Prevention (CDC), are correlated with higher rates of femur fracture and bone forearm fracture in a study of over 100,000 patients aged 4 to 10 years as compiled by the national insurance database PearlDiver, according to a new report from the Oregon Health and Science University.

The authors determined the weighted average of states’ fluoride level by multiplying the fluoride level in each county by the population of that county divided by the total state population, according to the report published in the October issue of the American Academy of Orthopedic Surgeons’ Journal of the AAOS Research & Reviews.

“The calculated concentrations of fluoride in per liter of drinking water based on the weighted averages of fluoride concentration by county population had strong positive correlations with fracture rates for all fracture types,” wrote the authors.

The report, which is generally uncritical of the fluoridation policy, contains an alphabetical list of all 50 states with their fracture data.

The authors conclude, “There has been little research investigating the effects of fluoride on bone in the pediatric population. It has been established that children retain more fluoride in bones than adults do, but the implications of this are unknown.”

FAN’s bulletin on the Study:

New Study: Fluoridated Water Weakens Children’s Bones

Source: http://dx.doi.org/10.5435/JAAOSGlobal-D-22-00221

Spittle Challenges Use of AI in Queries Regarding Fluoride Usage And Effects

In a recent editorial, Bruce Spittle, who is retiring as editor of the journal Fluoride, argues that the artificial intelligence program Chat Generative Pre-trained Transformer (ChatGPT) can’t be properly evaluated if its responses to questions on fluoride’s usage and side effects are compared to a “gold standard” that consists of the American Dental Association’s website.

Responding to a report from dental researchers at the Çanakkale Onsekiz Mart University in Turkey that appeared in the same issue of Fluoride, Spittle writes, “[Despite having] 175 billion parameters, ChatGPT had only limited knowledge of scientific developments that occurred after September 2021.”

He noted that when asked “Is water fluoridation safe?” ChatGPT said it was, and included in its response, “However, like any public health intervention, water fluoridation is not without controversy. Some people have raised concerns about the safety and ethics of water fluoridation. However, these concerns have largely been debunked by scientific research and expert panels.”

Spittle added, “There is very good quality evidence that the consumption of fluoride during pregnancy, at the levels used in community water fluoridation of approximately 0.7 mg/L, will result in an impairment in neurodevelopment resulting in a loss of IQ. An increase in fluoride of 1 mg/L in water and an increase of 1 mg/day of fluoride intake was associated with an IQ loss of 5.3 points and 3.66 points, respectively, for both boys and girls. This evidence indicates that the answer by ChatGPT to the question “Is water fluoridation safe?” should be: 

“Water fluoridation is considered unsafe when fluoride levels are maintained within the recommended range. …”

…rather than: 

“Water fluoridation is considered safe and effective when fluoride levels are maintained within the recommended range. ….”

As reported previously, Spittle’s editorials for the Fluoride journal are seen as the most relevant on the topic of fluoride as tabulated by the Web of Science database.

Source: https://www.fluorideresearch.online/563/files/FJ2023_v56_n3_p00i-0ii_sfs.pdf

Mullenix, Burgstahler Interviews on UMASS Library Site

Newly digitized interviews with Phyllis Mullenix and Albert Burgstahler made in 1998 that include personal commentaries on their experiences in the continuing efforts to stop water fluoridation have been posted on the CREDO digital site of the Du Bois Library’s Special Collections and University Archives (SCUA) department at UMASS Amherst.

The interviews are part of a series that Paul Connett made at the annual meeting of the International Society for Fluoride Research that year in Bellingham, WA. 

“Mullenix discusses her credentials and educational background; her research project that used computer analysis of video to detect toxin-induced aberrant behavior in rats; the results which show that prenatal exposure to sodium fluoride causes rats to be hyperactive; and the research establishment’s response to her findings,” according to the library site.

“Burgstahler discusses his personal experience with adverse effects from fluoride; association and collaboration with Dr. George Waldbott; collaboration with Pat Jacobs of Kansas City, MO on the study of the city’s fluoridated water’s effect on caimans and alligators in her care. Other topics covered include: a comparison of fluoride poisoning with lead poisoning, the danger of infant formula made with fluoridated water, and some discussion of the suppression of scientists who discovered harm from fluoride use,” according to the site.

The original video tapes were donated by Paul and Ellen Connett in 2021. SCUA’s Jeremy Smith, curator of the Daniel Ellsberg Papers, oversaw the digitalization and production of the videos and their posting on the UMASS site.




•• Michael Dolan can be contacted at <mdolan.ecsn@outlook.com>

•• The archives of The Fluoridation Review are available at: https://fluoridealert.org/about/fluoridation-weekly-review/