What do these mother-child studies really say about fluoridation?

A list of indicators of bad science – many of these are found in articles promoted by anti-fluoride activists.

Anti-fluoride activists have been pouring money into a scaremongering campaign warning pregnant women not to drink fluoridated water. They claim fluoride will lower the IQ of their future child.

Fluoride Free NZ (FFNZ)  launched this campaign on the back of the recent publication of Canadian research on fluoride intake by pregnant women and child IQ (see Ground Breaking New Study – Top Medical Journal – Fluoridated Water Lowers Kids’ IQs). Now they are responding to criticisms of this paper by claiming it is supported by other research and claim a list of 6 papers support their claim that pregnant women drinking fluoridated water may be harming the IQ of their children.

Image used by FFNZ as part of their appeal for finance to support billboards and newspaper advertising promoting their false scaremongering claim.

None of these studies actually support the FFNZ claim. Let’s consider each of the six studies listed by the Fluoride Action Network (FAN) – but first, look at this data from the “New Study – Top Journal” mentioned by FFNZ:

This is from Table 1 in  Green et al., (2019). There are no statistically significant differences in the IQ o children whose mothers lived in either fluoridated or nonfluoridated areas during their pregnancy. So the FFNZ claim is completely false.

The Fluoride Action Network (FAN) Bulletin Several In Utero Fluoride/IQ Studies Should Provoke A Nation-Wide Fluoridation Moratorium initially list 5 studies but expanded this to 6 studies in an article posted by Ellen Connett the same day – The 6 Mother-Offspring Fluoride Studies. Here is the list (descriptions are from the FAN articles):

  • Green et al.,  (2019). Largest study with 512 mother-offspring. Lower IQ in children 3- 4 years of age.
  • Bashash et al., (2017). Longest study. 299 mother-offspring pairs in Mexico. Lower IQ in children 4 and 6-12 years of age.
  • Thomas et al., (2018). 401 mother-offspring pairs in Mexico. Lower IQ in children 1-3 years of age Only the abstract has been published.
  • Valdez Jiménez (2017). Lower IQ between the ages of 3-15 months with 65 mother-offspring pairs in Mexico.
  • Li et al., (2004). Significant differences in the neonatal behavioral neurological assessment score in 91 offspring aged 1-3 days old.
  • Chang et al., (2017). Reported significant differences in the mental development index and psychomotor development index of the offspring at 3, 6, 9, and 12 months of age.

I will consider these in three groups and include some relevant theses.

The Chinese studies from areas of endemic fluorosis

These describe data from areas of endemic fluorosis in China. They are irrelevant to community water fluoridation as the drinking water fluoride concentrations are much higher and people in these areas suffer a range of health problems including severe skeletal and dental fluorosis. Remember, the optimum levels of fluoride recommended for community water fluoridation are generally below 1 mg/L and WHO recommends drinking water concentrations should be lower than 1.5 mg/L.

People in areas of endemic fluorosis suffer a range of health problems

Li, J., Yao, L., Shao, Q. L., & Wu, C. Y. (2008). Effects of high fluoride level on neonatal neurobehavioral development. Fluoride, 41(2), 165–170.

This is one of the generally poor quality studies FAN got translated to assist their campaign. They are generally published in Fluoride, an anti-fluoride journal.

It compared children from villages with drinking water concentrations of  1.7–6.0 mg/L with a control group from villages with drinking water concentrations of 0.5–1.0 mg/L.

Chang A, Shi Y, Sun H, Zhang L. (2017) Analysis on the Effect of Coal-Burning Fluorosis on the Physical Development and Intelligence Development of Newborns Delivered by Pregnant Women with Coal-Burning Fluorosis.

Another one of the poor quality papers  FAN got translated but they have made only the abstract and a brief exerpt available on their site. I cannot find a full test or even abstract anywhere else. It compares two groups:

“A total of 68 newborns delivered by pregnant women from coal-burning endemic fluorosis areas in this region were selected as an observation group, and 50 full-term newborns delivered by normal healthy pregnant women were selected as a control group. “

Both papers report statistically significant differences in some measurements between the two groups but that is to be expected for areas of endemic fluorosis and especially where coal-burning creates health problems. Of course, this is all irrelevant to community water fluoridation as only the control groups are likely to be drinking water with similar fluoride concentrations.

Mexican study from an area of endemic fluorosis

The paper is:

Valdez Jiménez, L., López Guzmán, O. D., Cervantes Flores, M., Costilla-Salazar, R., Calderón Hernández, J., Alcaraz Contreras, Y., & Rocha-Amador, D. O. (2017). In utero exposure to fluoride and cognitive development delay in infants . Neurotoxicology

This study found a relationship of child cognitive deficits with maternal prenatal urinary fluoride but, again, it is not relevant to community water fluoridation. The authors acknowledge that the study was done in an area of endemic fluorosis.  About 90% of the drinking water samples in the study contained fluoride above the World Health recommended maximum of 1.5 mg/l and the Fluoride in the mothers’ urine was also high – with the mean concentration for all the mothers of 1.9 mg/l  for the 1st trimester, 2.0 mg/l for the 2nd and 2.7 mg/l for the 3rd trimester. Urinary fluoride concentrations as high as 8.2 mg/l were found. This compares with a mean value for urinary F of 0.65 mg/L for pregnant women residents in areas with low levels of F in drinking water (0.4 to 0.8 mg/l – similar to that recommended in community water fluoridation).

I have written about this study in my post Premature births a factor in cognitive deficits observed in areas of endemic fluorosis? There I speculated that the effect of fluoride on cognitive deficits may be indirect because of the observede higher incidence of prematurity and low birth rate.

The Bashash study

I have separated these from the Green et al., (2019) study although they both report relationships between maternal prenatal urinary fluoride and the IQ of offspring and many of the authors are common to both studies  Bashash is the senior author on the paper reporting data from Mexico city and Green on the paper reporting data for Canada.

There are really three citations for this study. The main paper:

Bashash, M., Thomas, D., Hu, H., Martinez-Mier, E. A., Sanchez, B. N., Basu, N., … Hernández-Avila, M. (2017). Prenatal fluoride exposure and cognitive outcomes in children at 4 and 6–12 years of age in Mexico. Environmental Health Perspectives, 125(9), 8–10.

A conference poster:

Thomas, D., Sanchez, B., Peterson, K., Basu, N., Angeles Martinez-Mier, E., Mercado-Garcia, A., … Tellez-Rojo, M. M. (2018). OP V – 2 Prenatal fluoride exposure and neurobehavior among children 1–3 years of age in Mexico. Environmental Contaminants and Children’s Health, 75(Suppl 1), A10.1-A10. https://doi.org/10.1136/oemed-2018-ISEEabstracts.23

And Deena Thomas’s Ph. D. thesis which also reported data from the study:

Thomas, D. B. (2014). Fluoride exposure during pregnancy and its effects on childhood neurobehavior: a study among mother-child pairs from Mexico City, Mexico. University of Michigan.

The anti-fluoride activists have waxed lyrical about the reported negative relationship of child IQ with maternal prenatal urinary F concentrations but they are clutching at statistical straws as, in fact, the relationship is very weak – explaining only a few percent of the IQ variance. I explained this in my post Fluoride, pregnancy and the IQ of offspring, and described several other problems (correlation is not evidence of causation, information about the mothers is scant with no indication if they lived in areas of endemic fluorosis, possible important risk-modifying factors were not considered as confounders, urinary fluoride is not a good indicator of fluoride intake by individuals, and there was no association of child IQ to child urinary fluoride).

When data has this much scatter the marginal statistical significance of relationship are easily altered by tweaking the data. (Fig 3a from Bashash et al., 2017).

It is easy to be misled by marginal statistically significant relationships when considering data with such a high scatter. This is illustrated by the conclusions of one of the authors, Deena Thomas, in her Ph. D. thesis that:

“Neither maternal urinary or plasma fluoride was associated with offspring MDI scores” [page 37);

“This analysis suggests that maternal intake of fluoride during pregnancy does not have a strong impact on offspring cognitive development in the first three years of life.” [page 38];

“Maternal intake of fluoride during pregnancy does not have any measurable effects on cognition in early life.” [page 48].

Yet, in the conference poster  based on her thesis she concluded:

“Our findings add to our team’s recently published report on prenatal fluoride and cognition at ages 4 and 6–12 years by suggesting that higher in utero exposure to F has an adverse impact on offspring cognitive development that can be detected earlier, in the first three years of life.”

Her conclusions reported in her thesis are exactly the opposite of the conclusions reported in her conference poster!

I suggest in my article A conference paper on the maternal prenatal urinary fluoride/child IQ study has problems that the different conclusions in the poster resulted from the fact that at least 30 mother-child pairs were removed from the data set used in her thesis (the thesis consider 431 mother-child pairs but the poster considered only 401 pairs). Perhaps even some data pairs were added (the maximum urinary F value is higher in the smaller data set used for the poster).

In her thesis, Deena Thomas also reported: “concurrent urinary fluoride exposure has a strong positive impact on cognitive development among males aged 6-15 years.” [page 54]. The relationship was not significant for females. But the actual paper, Bashash et al., (2017), concluded “there was not a
clear, statistically significant association between contemporaneous children’s urinary fluoride . . . and IQ. “

I have discussed the Mexican maternal prenatal urinary fluoride- IQ study in more detail in the following articles:

A draft of my article critiquing the Bashash et al., (2017) paper, “Predictive accuracy of a model for child IQ based on maternal prenatal urinary fluoride concentration” is also available online. I have also discussed another paper from this study (Bashash et al., 2018) which reported a weak relationship of ADHD prevalence with maternal urinary fluoride in my article Fluoridation and ADHD: A new round of statistical straw clutching.

Green et al., paper/thesis

This study is actually the only one that included people exposed to community water fluoridation – hence the relevance of the data I presented in the introductory table which showed no effect. But the study it is basically the same as that of Bashash et al (2017) except it involved Canadian mother-child pairs and most of the criticism of Bashash et al., (2018)  are relevant to the Green et al., (2019) study which has been reported in the following forms:

Green, R., Lanphear, B., Hornung, R., Flora, D., Martinez-Mier, E. A., Neufeld, R., … Till, C. (2019). Association Between Maternal Fluoride Exposure During Pregnancy and IQ Scores in Offspring in Canada. JAMA Pediatrics, 1–9.

Green, R. (2018). Prenatal Fluoride Exposure and Neurodevelopmental Outcomes in a National Birth Cohort (MSc thesis, Graduate Program in Psychology York University Toronto, Ontario). 

My original critique included a conclusion that the reported negative relationship of child IQ with maternal prenatal urinary F concentration was extremely weak. I found that it explained only 1.3% of the child IQ variance using data extracted from the figures. Subsequently Rivka Green claimed an R-squared value of 4.7% which is still very low (we can reject her claim that it was “quite high” as simple promotion of her work).

For further discussion of the Green et al (2019) study see my articles:

A problem of self-promotion and confirmation bias

Science and the scientific literature are, of course, not immune to self-promotion and confirmation bais and I think the maternal urinary fluoride-child IQ studies show this. I discussed this in If at first you don’t succeed . . . statistical manipulation might help as well as pointing out that these scientific politics are amplified by activist propaganda.

This is a pity because such confirmation bias and self-promotion may result in important information being overlooked. I discussed this in  my article A more convincing take on prenatal maternal dietary effects on child IQ which referred to another paper from the Mexican maternal urinary fluoride study which showed a relationship of child IQ with maternal nutrition:

Malin, A. J., Busgang, S. A., Cantoral, A. J., Svensson, K., Orjuela, M. A., Pantic, I., … Gennings, C. (2018). Quality of Prenatal and Childhood Diet Predicts Neurodevelopmental Outcomes among Children in Mexico City. Nutrients, 10(8), 1093.

Again the relationships reported were weak, but the negative relationship of child IQ with poor prenatal maternal nutrition explains 11.2% of the variance in child IQ – much better than the data for prenatal maternal urinary fluoride (which explained only 3% of the variance).


So what do these mother-child studies say about community water fluoridation and IQ?

Well, nothing really – except that the only study which compared fluoridated and non-fluoridated areas showed absolutely no effect.

But this will not stop activists (and unfortunately self-promoting scientists and their institutions) from making unwarranted claims. Their propaganda relies on unsupported “authority” opinion and misrepresentation. This violates many of the rules in my first image above.

It tries to present correlation as proof of causation, misinterprets results, promotes unsupported conclusions, selectively reports the data and findings, and expands these unsupported conclusions way beyond the small sample sizes used.

This is just bad science!

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24 responses to “What do these mother-child studies really say about fluoridation?

  1. Bill Osmunson

    You are still avoiding the truth.

    The truth does not consist of one stream of evidence. OK, we get it. You disagree with JAMA Editors and some leading scientists, and I think you are wrong, but move on to other streams of evidence.

    Dosage and Benefit.

    You think the science of risk is low quality? Well, try your same critical skills evaluating benefit of fluoridation.

    You consistently avoid, evade, and remain silent on the tough questions.

    After all, if there is little or no benefit to health or cost, then risk is a mute issue. Instead you demand high quality studies of harm but appear to accept low quality studies of benefit.

    Your bias smells like a durian.

    Bill Osmunson DDS MPH


  2. Bill, you are a joke. Connett’s crowd reacts to a criticism of the Candian study that it is “just one study” by listing 6 studies. I look at all of them in turn and now you criticise me for considering only “one stream of evidecne.””

    The truth is you are running away from all those studies because, in fact, they do not confirm you bias (you cannot respond to my critiques) and refuse to provide any evidence to suit you.


  3. Bill Osmunson DDS MPH

    At least I’m making you laugh. . .you make me hold my nose. . . . Enough ad hominem.

    You are looking for proof of harm.

    I am looking for proof or at least some studies of safety (developmental neurotoxicity, cancer, tooth fractures, bone fractures, endocrine disruption, kidney, reproductive, mitochondrion effects, etc).

    We are approaching the problem from completely different ends. . . glass half full or half empty sort of idea. You demand I prove harm, I demand you prove safety and efficacy.

    Name one study on any toxin which is a perfect study. Based on your demands for quality scientific evidence, smoking, DDT, asbestos, lead, arsenic et al are safe because we do not have proof of harm at lower dosages. Where is your margin of safety, margin of error, uncertainty factors?

    And those promoting the increase in fluoride dosage for everyone have the moral and ethical obligation to provide high quality studies on safety. That is you, Ken. Yes, you promote increasing the dosage of fluoride for everyone regardless of age, health, gender, dosage from other sources, or even if they do not have teeth. It is YOUR obligation as promoter to provide the high quality studies on safety from developmental neurotoxicity. I’m not talking about endorsements, I’m demanding high quality scientific studies. They don’t exist and you refuse to respond.

    However, the USFDA starts out with the question of efficacy. After all, if fluoride is not effective, any discussions of dosage and safety are mute. The FDA has determined for years that the evidence of fluoride ingestion to mitigate dental caries is “incomplete.”

    Ken, you and I want quality studies, show the quality studies on efficacy. . . at any dosage. They don’t exist.

    After you establish efficacy at a specific dosage, then we can talk about safety at that dosage. Till then, your logic is spinning in circles and going nowhere, stuck.

    You are promoting more fluoride for everyone without good science, without measured evidence of existing intake, without measured evidence of health or cost benefit, and without a known dosage.

    I am fighting for safety for all. Stop fluoridation until we have quality studies.

    Bill Osmunson DDS MPH


  4. Come on Bill. You are saying “I am looking for proof or at least some studies of safety .” Well, these 6 studies are what the Connett crowd hang their collective hat on. they claim it “proves” fluoridation has a neurotoxic effect – but as you see that relies on misinformation and distortion.

    You came here to comment on these papers, or at least my critique of them – and I welcome comments on my posts.

    But you refuse to make any rational comments and in the process just concede all your ground. You don’t have a leg to stand on, do you? You cannot find any fault with my analyses or criticisms, cna you?


  5. Bill Osmunson DDS MPH


    You suggest I do not make “rational comments.”

    My comments are rational, you simply refuse to consider the concepts which do not support your bias.

    We should be able to agree that “everything is toxic,” “the dose makes the poison.” If you are uncertain, do an online search and watch the videos.

    Now take that concept to fluoride. Fluoride can be toxic. The question is, “at what dosage is fluoride toxic? For each species? For each gender? For each person?

    Do the studies on fluoride’s effect on the developing brain show harm at any dosage? Of course they do. Fluoride is lethal. . . it has been used as a rat poison and used to induce cancer in animals. At high enough dosages, fluoride is toxic. The toxicity of fluoride is without dispute.

    The question you continue to evade is dosage.

    To understand the studies, dosage must be compared. You are hiding the evidence by lumping the dosages together.

    You will not understand fluoride until you grasp the concept of dosage and determine how much fluoride is an individual is ingesting from all sources, how much fluoride do they need, how much is too much and does the person need to supplement their intake of fluoride.

    Dosage is the foundation of pharmacology, nutrition, toxicology, etc.

    Look at dosage of the studies and you will be convinced they show fluoride is a developmental neurotoxic substance at very low dosages, fluoridation dosages, for many individuals.

    Bill Osmunson DDS MPH


  6. Bill Osmunson


    The US National Toxicology Program has been reviewing fluoride’s developmental neurotoxicity. Their draft report of about 175 pages is worth reading. I just received a copy today.

    In part the report states: “The human body of evidence provides a consistent pattern of findings that higher fluoride exposure is associated with decreased IQ in children.”

    “Conclusions: NTP concludes that fluoride is presumed to be a cognitive neurodevelopmental hazard to humans. This conclusion is based on a consistent pattern of findings in human studies across several different populations showing that higher fluoride exposure is associated with decreased IQ or other cognitive impairments in children. However, the consistency is based primarily on higher levels of fluoride exposure (i.e., >1.5 ppm in drinking water). When focusing on findings from studies with exposures in ranges typically found in the United States (i.e., approximately 0.03 to 1.5 ppm in drinking water, NHANES (Jain 2017)) that can be evaluated for dose response, effects on cognitive neurodevelopment are inconsistent, and therefore unclear. There is inadequate evidence to determine whether fluoride exposure lowers IQ or impairs cognitive function in adults. There are few human studies available that provide data to evaluate whether fluoride exposure is associated with other neurodevelopmental effects, beyond IQ or other cognitive measures. Although conclusions were reached by integrating evidence from human and animal studies with consideration of relevant mechanistic data, the conclusions are based primarily on the human evidence. The evidence from animal studies is inadequate to inform conclusions on cognitive effects, and the mechanisms underlying fluoride-associated cognitive neurodevelopmental effects are not well characterized.”

    Ken, once again you need to think about dosage. Water at 1.5 ppm for the “mean” intake of 1 L/day of water is about the same as the 90th percentile drinking 0.7 ppm. In numbers we are talking about 10% of 200,000,000 Americas. . . 20,000,000 during part of their lives.

    Dosage, Ken. Your review of literature does not keep in mind dosage.

    Bill Osmunson DDS MPH


  7. Bill, this NTP draft appears to have been taken down. Can you please send me your copy or a link that works?


  8. Bill, who sent you a copy of the report? I thought as it was subject to peer review so can not represent NTP policy that it would not be publicly available.


  9. Why no reply, Bill?

    I asked because this draft report is not publicly available on the NTP site. It also includes the customary disclaimer for a pre-peer-review draft:

    “This DRAFT Monograph is distributed solely for the purpose of pre-dissemination peer review under the applicable information quality guidelines. It has not been formally disseminated by NTP. It does not
    represent and should not be construed to represent any NTP determination or policy”

    So I think there must be a leaked copy circulating and I do notice that the Fluoride Action Network makes it available on their own web site. That is, it links to the leaked copy FAN has – not to the NTP.

    Rather annoying to have to deal with this in its draft form as the final, official, version could be quite different. But as the anti-fluoride activists are intent on misrepresenting the content I guess I will have to.


  10. Bill Osmunson DDS MPH

    You have a sister view of science. As I said, this is a “draft.” However, if the past is any indication, I doubt there will be any changes other than perhaps typos. Even if NTP is persuaded to change it, this is the current thinking of those scientists. The report should have been stronger.

    Currently, EPAP has 4.0 ppm as their Maximum Contaminant Level Goal for fluoride in water. And as you know, not everyone drinks the same amount of water. I expect the MCLG will be lowered.

    And the “King” of refusing to answer my questions on dosage complains because I do not answer?

    If you were a prescribing doctor or Pharmacists or Toxicologist, one of the first questions you would ask is “dosage.”

    Your serious flaw is failure to consider dosage with the theory of fluoridation and each study you review.

    Bill Osmunson


  11. Bill Osmunson DDS MPH

    Corrections. . . sinister not sister and EPA not EPAP.

    Dosage, Ken. Dosage, Ken.

    Think Dosage. Dig into dosage.

    Answer the fundamentals on how much fluoride are people ingesting (everyone), how much should they ingest for benefit (if any), how much are they ingesting for safety (if risk), and how much if any should be supplemented.

    With each study, keep in mind dosage. Until you respond to those questions, you are simply blowing smoke.


  12. Bill Osmunson DDS MPH

    This works for me.


    Dosage, Ken. Think Dosage. Answer questions on Dosage. NTP’s draft review makes a stab at part of the dosage questions for the studies on developmental neurotoxicity but not benefit, other risks, or total exposure.


  13. Thanks for the link, Bill. It is the link provided in the Bloomberg article where I got my copy.

    However, you said

    “I just received a copy today.”

    And I asked:

    “Bill, who sent you a copy of the report? “

    Obviously, someone has been sending copies of the leaked report to “trusted” anti-fluoride activists as part of a campaign.

    This report is not a priority for me at the moment (dealing with the ADHD paper now) but I will get to it later.

    You clearly do not understand or wish not to understand, the nature of a draft and of peer review of a draft like this. The NTP lists as objectives for the peer review:

    “Has the systematic review protocol been followed and modifications appropriately documented and justified?
    Does the monograph accurately reflect the scientific literature?
    Are the findings documented in a consistent, transparent, and credible way?
    Are the report’s key messages and graphics clear and appropriate? Specifically, do they reflect supporting evidence and communicate effectively?
    Are the data and analyses handled in a competent manner? Are statistical methods applied appropriately?
    What other significant improvements, if any, might be made in the document?
    Does the scientific evidence in the NTP Monograph support NTP’s hazard category conclusions for fluoride in children and adults?”

    You are completely wrong to claim “there will be [no] changes other than perhaps typos.” As someone who has been through peer review, and carried out peer review many times I can assure you that while it is not particularly common for data to be found faulty and rejected there are certainly many changes to opinions expressed in the reports, conclusions, and interpretations.

    I certainly look forward to improvements the peer review will suggest.

    For example, the sentence:

    “Due to heterogeneity in the endpoints examined and the limited number of human or animal studies, congenital neurological malformations and neurological complications of fluorosis were not evaluated because the body of evidence was inadequate to evaluate these potential effects.”

    I hope they do in fact at least discuss this because the issue is raised in some papers and the fact is some research cannot produce a relationship of IQ with drinking water F but do find a relationship with severe dental fluorosis.

    At the moment my initial scan through the report confirms my understanding of the data – that reports of an apparent effect of fluoride on IQ are restricted to higher fluoride concentrations, not relevant to community water fluoridation. But I do think there is room for improvement in some of the opinions and evaluations expressed in the report. I imagine this will happen, especially as there is now a recorded list of problems with the Green et al paper which the report was not in a position to take into account and hence did not evaluate the paper correctly.


  14. Bill Osmunson DDS MPH


    Hierarchical evidence is a house of cards.

    The fatal flaw in your understanding of fluoridation starts with dosage.

    You state, “that reports of an apparent effect of fluoride on IQ are restricted to higher fluoride concentrations, not relevant to community water fluoridation.”

    Concentration is not dosage.

    Not everyone drinks the same amount of water.

    The mean drink almost 1 liter of water per day.

    90th percentile 2 liters of water. In other words, 10% of the public are ingesting twice as much fluoride from water as the mean.

    A few drink over 10 liters of water per day or ten times as much fluoride as the mean.

    And further, not everyone has the same body size. You and a baby do not weigh the same. Dosage is mg/Kg body weight, not concentration of a substance in water.

    And we have not included chemically sensitive individuals.

    And we have not included an uncertainty factor.

    And we have not included any margin of error.

    To suggest studies with fluoride greater than 1.5 ppm in water are showing developmental neurotoxicity and that is not relevant to water fluoridation is a serious laps in understanding.

    You consistently avoid dosage and will consistently make poor judgment failing to consider dosage.

    Bill Osmunson DDS MPH


  15. Bill Osmunson DDS MPH

    And Ken, you asked “who sent me a copy.”

    My good friend Google.

    Bill Osmunson DDS MPH


  16. What a laugh, Bill – “My good friend Google.”

    Why are you so ashamed to admit that your FAN mates were circulating this draft -after all they post it on their site?

    But perhaps you should read the draft to see how they explain the fact that any supposed effect only occurs at higher concentrations. And, no, they do not use the word “dosage” in the report. Most use of the term dose in the report refers to water concentration.


  17. Bill Osmunson DDS MPH

    The fatal flaw in your reasoning is dosage.

    You are too bull headed to stop and consider dosage.

    Note: “A dose refers to a specified amount of medication taken at one time. By contrast, dosage is the prescribed administration of a specific amount, number, and frequency of doses over a specific period of time.”

    Yes, dose is sometimes used to refer to the amount of fluoride added to water. However, the intent of increasing the concentration of fluoride in water is to give humans an increased dosage of fluoride.

    It appears the concept of dosage is beyond your comprehension. So lets talk about simple math.

    mgF/Kg body weight/day. That is what we are talking about, dosage. Three items.

    The “per day” is obvious.

    The “body weight” is obvious, an infant weighs less than you or me.

    The sticking part for you appears to be the milligrams. We are NOT talking about treating water which is now close to 0.7 ppm. The purpose of fluoridation is to increase the patient’s dosage of fluoride.

    Total water intake plus other sources of fluoride each day, equals the total fluoride exposure. Divide that by the patient’s body weight and we get dosage of fluoride. (We still don’t know individual retention of the fluoride which is dependent on kidney function, etc.)

    Good scientists know it is unrealistic to measure the total individual intake of fluoride (all sources, toothpaste, medications, foods, post harvest fumigants, etc.). Therefore, research needs to be done where there is little other fluoride sources than water (a good location would be in China). OR, actually measure the urine and/or serum fluoride concentration which also has limitations.

    Research perfection? Hardly. But we can gain insight into the direction the research is going.

    To show significance in a larger population, NTP found the fluoride water concentration needs to be over 1.5 ppm. Considering about half the fluoride in the USA is from other sources than water, and many of the studies done are in areas where the fluoride is mostly from water, our 0.7 ppm is similar to the 1.5 ppm from those studies.

    OR, another way of looking at it is the amount of water people drink. About 10% of the population, (about 20 million in the USA) drink double the “mean” amount of water which is similar to 1.5 ppm.

    Ken, because you fail to focus on the science, you start talking about people. If you want me to move from science to people, we can do that.

    As a Russian supporter, pleased the Russians altered the USA elections and is harming other countries, do you have a perverse desire to lower the IQ of the USA with fluoridation in order to support Russia?????

    Or perhaps the quality of science you accept is the anecdotal evidence from a patient and a few clinicians in Calgary that caries has increased???

    You demand high quality of science proving harm from your beloved fluoride, but you accept anecdotal evidence of efficacy. The bias stinks.

    If you are going to try and be a scientist, be objective and demand the same quality of science on efficacy and safety, remembering that we can do RCT of efficacy but not safety. Judgment is different for each.

    Bill Osmunson DDS MPH


  18. Bill Osmunson DDS MPH

    Do you see where I sort of screwed up on the term’s dose and dosage, in the above post? The two sort of get mixed up with fluoridation because every glass of water is a dose and we have several doses over the day for dosage.

    Bill Osmunson DDS, MPH


  19. Bill, personal attacks are usually a sign that one lacks confidence in one’s argument. But I will bite.

    You say I am a “Russian supporter.” What can that possibly mean? Do I give Russia money? Do I wave the Russian flag? Do I partisanly support their sports teams? Of course, none of that is true.

    Or is it simply your way of you recognising that I am not taken in by racist, xenophobic Russiaphobia? That I look for the truth rather than support a particular political or geopolitical player. I can see objectively the role played by countries like the Russian Federation and the USA because, in fact, I have no loyalties except to the truth and to seeing all humans as equal.

    Russia is harming other countries? That may be true but what do YOU mean. They do pursue their own interests internationally but considering, say, Venezuela or Syria Russia is providing much-needed help whereas it is the USA that actively seeks to harm these countries. Cause their people to suffer – all in an attempt to change regimes.

    How can I lower the IQ of the USA with fluoridation? I have no effect on US policies, but there is absolutely no evidence that fluoridation influences the IQ of Americans (except maybe indirectly and positively in later life because of better dental health). Mind you there appears to be plenty of evidence that racist, xenophobic Russophobia, actively promoted by the DNC and Clinton, has had a huge negative effect on the IQ of Americans. The very fact that you can put up such a puerile argument says a lot about your low IQ – and it appears that the problem is a result of the crazy political atmosphere in your country.


  20. Bill,

    If Community Water Fluoridation is as toxic as you claim, and has the deletarious effects that you claim, then why don’t you just prove it?

    CWF has been around for many decades. Millions of people worldwide have been exposed for their entire lifetimes.

    The duration humans have used CWF means that there is real evidence out there to determine whether or not CWF has an effect on IQ. Not a postulated effect based on poor research, but a real effect found in the real world.

    Within the UK there are still many non-CWF communities. Those communities can be readily identified through public records, and can then be matched with otherwise similar CWF using communities.

    The UK has had standardised school examinations for many decades. That means that every child in the country sits exactly the same examinations. The results of those examinations are available by district, even by individual school. Examination results between districts and schools with and without CWF can be directly compared. Examination results of individual schools and districts can even be compared before and after CWF in some cases.

    If you wish, you can also get health outcomes by district from the UK National Health Service and compare health data, even including dental outcomes, between CWF and non-CWF districts. That’s a benefit of having government supplied health services – there’s always a record kept.

    It’s all there, on public record. Reality. Millions of people in the real world compared with the few hundred from Green’s paper.

    You claim that CWF is toxic and reduces IQ. I’ve pointed out that there is real world data out there to either substantiate or refute your claim. Why don’t you use it instead of just speculating and spreading FUD?


  21. Bill Osmunson DDS MPH


    If CWF is safe as you claim, show the safety studies you rely on.

    It is not the duty of those being forced to ingest the poison to prove safety. The duty lies in those marketing the poison.

    All states and countries I have examined have definitions of poisons or highly toxic substances. For example, Washington State:

    “RCW 69.38.010

    “Poison” defined.

    As used in this chapter “poison” means:
    (1) Arsenic and its preparations;
    (2) Cyanide and its preparations, including hydrocyanic acid;
    (3) Strychnine; and
    (4) Any other substance designated by the pharmacy quality assurance commission which, when introduced into the human body in quantities of sixty grains or less, causes violent sickness or death.”

    As you know, 60 grains is about 3,889 mg.

    I asked the pharmacy quality assurance commission (then known as the Board of Pharmacy) if fluoride was a poison, they confirmed it was.

    Fluoride can be lethal at . . . well there are no randomized controlled trials on the lethal dose of fluoride for humans, so we have to take estimates which range from 5 mg to 20 mg.

    Back to dose and dosage. What dosage would be considered lethal for a 5 Kg infant? Perhaps 25 mg to 100 mg of fluoride.

    Ken, 100 mg is less than 3,889 mg. I know that stretches your paradigm, but that is the law. A poison is exempt from poison laws when regulated as either a pesticide or drug. Fluoride when used to mitigate dental caries is classified as a drug. However, the FDA has never approved swallowing fluoride as a drug. Therefore, either you are promoting an illegal drug or a poison.

    Please provide your safety studies or evidence of drug approval or any quality scientific evidence fluoride is safe at dosages ingested by humans.

    Here is one judges ruling on fluoride as a post-harvest fumigant:

    ” Regarding Fluoride Post-harvest fumigant, the EPA Judge concluded:
    “EPA agrees that aggregate exposure to fluoride . . . does not meet the safety standard in FFDCA section 408.”

    “The fluoride MCLG is not protective of the effects of fluoride on teeth and bones;

    “The fluoride MCLG is not protective of other neurotoxic, endocrine, and renal effects of fluoride;

    “EPA has not adequately protected children

    “EPA cannot determine the safety of sulfuryl fluoride and fluoride in the absence of a developmental neurotoxicity study

    “EPA has underestimated exposure to fluoride; and

    “EPA has committed procedural errors in violation of the Administrative Procedures Act (APA) (5 U.S.C. 551 et seq”

    Until you can provide quality studies on safety and efficacy at current dosages, I will maintain CWF is an illegal drug, highly toxic poison, unethical and immoral to force everyone to swallow. And those promoting the illegal drug should be held personally accountable.

    Bill Osmunson DDS MPH


  22. Bill, you surely don’t think I, or my other readers, are that stupid, do you?

    This post shows the best 6 studies the Conmnett crowd can find ti “prove” fluoridation harmful actually don’t do that. They are either completely unrelated to fluoridation or extremely weak and suffer from disingenuous statistical manipulation.

    You have been unable to present even one argument against the facts and logic in y post. So you then resort to a naive logical myth – asking me to provide a negative. Just think about it – there are absolutely no studies showing that water is safe to drink. But just as with fluoride at concentrations used in CWF, there are plenty of studies that have tested for harm and found none.

    But to get back to the crude and unwarranted political attack on me. Having sunk so low you prove you can sink even lower by refusing to apologise for that attack and are now pretending it didn’t happen.

    What about responding to my questions:

    “You say I am a “Russian supporter.” What can that possibly mean? Do I give Russia money? Do I wave the Russian flag? Do I partisanly support their sports teams? Of course, none of that is true.

    Or is it simply your way of you recognising that I am not taken in by racist, xenophobic Russiaphobia? That I look for the truth rather than support a particular political or geopolitical player. I can see objectively the role played by countries like the Russian Federation and the USA because, in fact, I have no loyalties except to the truth and to seeing all humans as equal.

    Russia is harming other countries? That may be true but what do YOU mean. They do pursue their own interests internationally but considering, say, Venezuela or Syria Russia is providing much-needed help whereas it is the USA that actively seeks to harm these countries. Cause their people to suffer – all in an attempt to change regimes.

    How can I lower the IQ of the USA with fluoridation? I have no effect on US policies, but there is absolutely no evidence that fluoridation influences the IQ of Americans (except maybe indirectly and positively in later life because of better dental health). Mind you there appears to be plenty of evidence that racist, xenophobic Russophobia, actively promoted by the DNC and Clinton, has had a huge negative effect on the IQ of Americans. The very fact that you can put up such a puerile argument says a lot about your low IQ – and it appears that the problem is a result of the crazy political atmosphere in your country.”


  23. Bill Osmunson DDS MPH


    If you think you and your readers are that stupid, I will protest.

    You are not stupid. Misguided, wrong, and ignorant of some aspects of drug safety, but not stupid.

    You said, “there are plenty of studies that have tested for harm and found none.”

    No, Ken, you are speculating that proof of safety is a study which finds no harm. Substances are not found to be safe simply because we don’t carefully evaluate them.

    The best place to learn about safety studies is at http://www.fda.gov. They are tasked with determining the safety of all substances used with the intent to treat or prevent disease in man and animals. FDA has a great deal of guidance documents for manufacturers. Specific trials which must be provided to the FDA for evaluation.

    And all substances used with the intent to prevent or treat disease have a label which tells the consumer about dosage as well as risks and side effects. All substances used with the intent to prevent or treat disease have side effects and all have labels of dosage and warnings, even toothpaste.

    The FDA scientists are tasked with the role of determining whether the safety studies at a specific dosage are appropriate. But fluoride never got to that point because the FDA said the evidence for efficacy was incomplet.

    In other words, Ken, swallowing fluoride doesn’t work. End of discussion.

    You refuse to talk about dosage because you do not have a leg to stand o and clueless on dosage, total exposure, all ages..

    You refuse to talk about safety studies except to say there are plenty of studies.

    And you refuse to talk about efficacy providing quality studies.

    Now to your first love, RT news. You clearly follow it and quote from it.
    But lets stick to science.

    Bill Osmunson, DDS MPH


  24. Bill, you do realise that RT has pushed anti-fluoride messages through one of their US editors, don’t you? I thought you would have been on board because her video is often used by anti-fluoride activists.

    One of the local anti-fluoride personalities uses a photo of Putin on his facebook page – obviously a fan.

    You see, the world is not as simple as you think.

    the fact remains, you have been unable to find any flaw in my article – I must assume you now accept that these 6 studies promoted by Connett’s crowd are unreliable as evidence.


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