A Reasonable Campaign to Fluoridate Our Drinking Water

fluoride-waterBy Tia Will

On Tuesday, Alan Pryor and Pam Nieberg submitted an article in opposition to fluoridation of our drinking water. They stated their opinion that the proponents of fluoridation were using stealth tactics and attempting to stifle debate and consideration of other points of view. This is demonstrably inaccurate as was seen at the April 25th meeting of the WAC when the proponents gave their formal presentation on the advantages of fluoridation in a public, televised forum.

There is one point on which the opponents and I fully agree. Any public policy decision should be based on a full consideration of the risks and benefits of the planned action. All points of view should be heard and all concerns should be addressed. However, this is where we part company. As a doctor, I believe in evidence-based decision making using the best information sources available. The opponents of fluoridation do not seem to support this approach.

Here, I will address only the medical and public health issues. An area of agreement is that fluoride, in appropriate levels, is highly effective in the prevention of cavities. This is true whether taken orally, either in the water supply or as supplements, or when applied topically as a dental treatment. Ingestion is effectively equivalent to topical application since fluoride enters the saliva, which continually bathes our teeth. Since dental decay and cavity formation are major health problems for both children and adults, provision of safe levels of fluoride in the drinking water would seem to be a cost effective means to provide this demonstrated preventive health care to the entire population regardless of the individual’s ability to pay for supplements and dental care.

I also believe that concerns about potential risks of fluoride supplementation should be fully addressed. I will focus on four main areas of concern expressed by the opponents to date: neurologic consequences, cancer risk, osteoporosis/fluorosis, and the effects on vulnerable populations.

Neurotoxicity:

One opponent stated that there are “many studies” showing that fluoridated water is associated with lower IQ’s in children. This would be a truly sobering thought if relevant to our situation. However, close evaluation of the meta-analysis from the Harvard School of Medicine 2012, which included a review of 27 studies from China and Iran demonstrates the safety of fluoride at the amounts proposed for our water supply. If one read only the abstract and conclusion one might be alarmed by their findings that naturally occurring fluoride at very high levels is associated with a slight decrease in IQ. However, closer evaluation of the data shows that the “reference group” namely the high IQ children were, in about half of the studies, exposed to fluoride levels of 0.7 mg/l or higher, the amount proposed for our water supply.  For me, rather than supporting the risk, this clearly demonstrates the safety of fluoride at the proposed level. The article’s authors even go so far as to admit that it would be difficult to generalize the results to more industrialized countries since fluoride levels rarely exceed 1 mg/l in drinking water.

Cancer risk

Using peer reviewed articles, there is only one type of cancer that has ever been suggested to be associated with fluoride. This is osteosarcoma, a rare form of bone cancer which in adolescents is diagnosed approximately 400 times per year in the US. This association is based on a single study in which rats were fed fluoride at much higher doses than are being proposed for our water supply. These rats did indeed show a very slight increase rate of osteosarcoma. However, there were major problems with this study: 1) it used rats and animal studies are notoriously inaccurate in predicting human effects; 2) dosages were far higher than are proposed for Davis water; and 3) it has never been replicated. What is more important is that despite 65 years of use of fluoridation in our water supply, there has been no increase in the overall incidence of osteosarcoma, nor is there a difference in the incidence of osteosarcoma in populations with fluoridated water as compared with those without. Sixty-five years would certainly be enough time to see this effect if it existed.

Osteoporosis/Fluorosis risk

Again, relative levels of fluoride are the key. Many substances taken in small amounts are beneficial while clearly toxic at excessively high levels. Tylenol is a good example. Take two and your headache improves. Take 200 and you are likely to die from liver failure. It is true that if fluoride is given at very high levels, many times that proposed, there is a risk of increased bone fragility with increased fracture risk. Likewise, at very high levels, there is an increased chance of developing the largely cosmetic condition, fluorosis, at much higher levels than those proposed, but not at the proposed level.

Vulnerable populations

If is hard for me to imagine more vulnerable populations than fetuses and children.

The former are within my area of expertise as an obstetrician-gynecologist. Fluoride is classified as a category B medication meaning that it is safe for maternal use at recommended levels throughout pregnancy. I am not an expert in pediatrics, but my pediatric colleagues are all in favor of fluoridation of the water supply.

From an evidence-based point of view, what is increasingly clear to me from the perspective of preventive medicine and public health, is that the evidence in favor of water fluoridation far exceeds the theoretical, unproven risks. Therefore, I am strongly in favor of implementation.

Tia Will is a local gynecologist and a member of the Vanguard Editorial Board.

Author

  • David Greenwald

    Greenwald is the founder, editor, and executive director of the Davis Vanguard. He founded the Vanguard in 2006. David Greenwald moved to Davis in 1996 to attend Graduate School at UC Davis in Political Science. He lives in South Davis with his wife Cecilia Escamilla Greenwald and three children.

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60 comments

  1. SODA

    There are many, many other concerns that opponents raise. My so far limited literature search and article space did not permit me to address many of the stated concerns. I will be watching off and on today and will try to respond to as many questions as folks may have.

  2. I would suggest in the near future the DV have a point counterpoint on the issues both sides raise in same article, eg pro states benefits (cons address that); cons state neurological concerns (pros address it). I had hoped for this with water issue and again suggest it. Your article is a good start, but you have blown your cover you know 🙂
    Sorry for typos, on BART to SF

  3. This article cites studies and experts with a whole different view of the effects of fluoride and fluoridated water:

    [url]http://thyroid.about.com/cs/toxicchemicalsan/a/flouride.htm[/url]

  4. It’s been blown for a while ! It was only a matter of time ; )

    I don’t know if we can organize a point/ counterpoint in the same article. Maybe David could help us out with getting that together.

    What could easily be done is to have a point by point discussion in the comments to this article. I am really sincere in my view that full discussion is a value to the community and I would invite Alan Pryor, Pam Nieberg, and any other opponents ( or proponents ) to join me in such a discussion.

  5. So what is the expertise of the author of that article? Are they qualified to evaluate the studies they cite? Why are those citations so old (late 90s) when there have been very recent studies by the EPA and CDC with very different findings? In short, are you simply posting the article because you agree with their conclusions? Do you have any insight into whether that article is accurate?

  6. “A recently-published Harvard University meta-analysis funded by the National Institutes of Health (NIH) has concluded that children who live in areas with highly fluoridated water have “significantly lower” IQ scores than those who live in low fluoride areas.”

    [url]http://www.huffingtonpost.com/dr-mercola/fluoride_b_2479833.html[/url]

  7. This is just another bad example of overblowing research findings.

    Headline: “Harvard Study Confirms Fluoride Reduces Children’s IQ”

    Except for one problem it doesn’t confirm anything. Instead the study finds: “In conclusion, our results support the possibility of adverse effects of fluoride exposures on children’s neurodevelopment.”

    Big difference.

    Do you know what a meta-analysis is? It’s basically a research-review that looks across studies and tries to come up with a new finding. But it’s based on the veracity of the other studies.

    At the same time, the article suggests that 70 percent of water supplies have fluoride. Such a big exposure over such a long period of time and yet as the author writes, there is not “a scientific consensus” against fluoride now.

    I don’t have an opinion on this issue – yet. [u][b]But stop just spamming the board with studies[/b][/u], because you are CHERRYPICKING the studies you like and ignoring the ones you don’t like.

    When I looked over the last few days there are plenty of studies on both sides of the issue that on the surface appear reputable.

  8. In preparation for the fluoridation discussions on the WAC I decided to try and take myself back to “ground zero” and sought out information over the past four weeks from both the anti-fluoridation and pro-fluoridation camps. The 2006 NRC Study information that Growth Izzue has linked was also provided to me by Barbara King in the form of a Scientific American article published in 2008 (see [url]http://www.scientificamerican.com/article.cfm?id=second-thoughts-on-fluoride[/url]).

    The Harvard article linked by Growth Izzue confirms what I found when I tried to find follow-up studies that addressed the concerns raised in 2006 by the NRC. My thoughts were that in the seven years since 2006 there wold be some effort made (and subsequently published) to determine whether the concerns could be confirmed with further scientific study. Unfortunately, the seven years do not appear to have produced any such confirmation . . . but I am still looking.

    The wording of the Harvard meta data study is worth taking a look at. I have bolded several sentences that (as a deliberating member of the WAC) I think are very important.

    [i]A recent report from the U.S. National Research Council (NRC 2006) concluded that adverse effects of high fluoride concentrations in drinking water [b]may be of concern and that additional research is warranted.[/b] Fluoride may cause neurotoxicity in laboratory animals, including effects on learning and memory …

    To summarize the available literature, we performed a systematic review and meta-analysis of published studies on increased fluoride exposure in drinking water and neurodevelopmental delays. We specifically targeted studies carried out in rural China that have not been widely disseminated, thus complementing the studies that have been included in previous reviews and risk assessment reports …

    Findings from our meta-analyses of 27 studies published over 22 years suggest an inverse association between high fluoride exposure and children’s intelligence … The results suggest that fluoride may be a developmental neurotoxicant that affects brain development at exposures much below those that can cause toxicity in adults …

    Serum-fluoride concentrations associated with high intakes from drinking-water may exceed 1 mg/L, or 50 Smol/L, thus more than 1000-times the levels of some other neurotoxicants that cause neurodevelopmental damage. Supporting the plausibility of our findings, rats exposed to 1 ppm (50 Smol/L) of water-fluoride for one year showed morphological alterations in the brain and increased levels of aluminum in brain tissue compared with controls …

    In conclusion, our results support the possibility of adverse effects of fluoride exposures on children’s neurodevelopment. [b]Future research should formally evaluate dose-response relations based on individual-level measures of exposure over time[/b], including more precise prenatal exposure assessment and more extensive standardized measures of neurobehavioral performance, in addition to improving assessment and [b]control of potential confounders[/b].[/i]

    The bolded words appear to be calling for the same kind of follow-up study by the opponents of fluoridation that the NRC was calling for in 2006. I find myself wondering when those follow-up studies will indeed be undertaken.

  9. [quote]This article cites studies and experts with a whole different view of the effects of fluoride and fluoridated water:

    http://thyroid.about.com/cs/to…ouride.htm[/quote]

    I am aware of this article, but have not yet done the literature search with regard to potential effects on the thyroid. I have an appointment in Sacramento this am and will get back to you on this specific issue later in the day.

  10. [quote]When I looked over the last few days there are plenty of studies on both sides of the issue that on the surface appear reputable.[/quote]

    And because this does appear to be the case, at least in the “pro” and “con” authors, I have chosen to take a different, but very time consuming approach. For each of the issues raised, I am doing a literature search,
    consulting with the appropriate specialist who presumably would be aware of studies that I have not unearthed, and also researched the unbiased literature on each specific condition to see if I can find any linkage of fluoride to this condition. Obviously, this takes a while, so bear with me and I will attempt to get as much information as I can.

  11. [quote]But stop just spamming the board with studies, because you are CHERRYPICKING the studies you like and ignoring the ones you don’t like.
    [/quote]

    Remember that you wrote this when you write your columns and cite studies and articles that back your thesis.

  12. The article on about.com is by Mary Shomon, a health educator. The title is: “Hidden Danger in Your Drinking Water and Toothpaste.” Many of the studies cited are the same ones cited in other articles – the rats and neurotoxicity article, the University of Iowa study on fluoride in sodas, etc. She goes on to link fluoride to hypothyroidism: “Is fluoride in part the reason for near epidemic levels of hypothyroidism in the United States? Some experts and researchers believe this is the case.” She quotes Andreas Schud, whose article on rense.com is a screed against fluoride. Ms. Shomon’s article is basically anti-fluoridation.

    One of my major problems with the anti-fluoridation proponents is that the science is piecemeal and does not offer a cogent, systematic story about why fluoridation is bad for us. The articles are few and far between. (Yes, a long list of articles can be made, but they are not from the same labs or authors, there is no progression from one to the next, and – like many areas of empirical research – validation and replication studies are rare.)

    There is no sustained body of research to show connections between the chemistry of fluoride and bad outcomes. The Harvard metaanalysis – by the author’s own admission – suffers from the poor quality of many of the studies aggregated. The neurotoxicity in rats study is a far cry from a randomized trial of fluoride in humans. In my experience reading the research in neuroscience and social science, animal models are meant to be followed up at some point to humans or at least primates.

    Science is incremental and evidence for a phenomenon often takes a long time to build up. Consensus is important in advancing a field. Breakthroughs are rare and often are ignored or derided until supporting evidence arrives and things shift. Plate tectonics and the origins of stomach ulcers in h pylori not stress are two good examples of changes in paradigm that heralded in brand new views of the world.

    Fluoridation, in my view, simply has not made much of a dent in the scientific community because there simply is not much there. One way to measure the impact of a field of research is to look at research funding. I couldn’t find a single reference for how much money has been spent on fluoridation research. Of course, that doesn’t mean there isn’t research or it shouldn’t be done, but it is one indication of the importance the scientific community puts on this area of research.

    I don’t think it is, as one proponent of fluoridation put it: “a no-brainer,” rather I think it’s a “reasonable brainer.” I am a proponent of fluoridation because the benefits seem to outweigh the costs – by a wide margin. And nobody has offered a decent theory about why fluoride is bad for you and no one has been able to falsify the generally positive benefits of fluoride in drinking water.

  13. The following is primarily for the author who had already done the research, but I also appreciate anyone else who might kno

    According to another thread, toxicity effect depends on body weight. Assuming that this relation is linear, a baby of 10kg is 4 times as vulnerable to a child of 40kg.

    For the water system, Fluoride is regulated by concentration. The safe level of concentration can only be concluded with consideration of the ingestion at all reasonable body weight, and with consideration of Fluoride ingestion from other existing sources.

    According to the above concepts, for the reader to make sense out of the section “Neurotoxicity”, the reader must know these numbers:

    1) In the study, what is the toxicity level, per body weight, associated with lower IQ? (Suggested unit: mg/kg)

    2) What is an estimation of the the existing Fluoride ingestion level (other than from drinking water). (Suggested unit: mg/day)

    3) How fast does Fluoride exit from the body? (Suggested unit: mg/day)

    4) What is the proposed Fluoride concentration for the water system?

    5) What is the concentration of Fluoride already in our water system?

    From these numbers, it is possible to derive the following information:

    a) Given a regulated Fluoride level, we can calculate the amount of water a person can safety drink in each body weight class. For example, if the numbers are these:

    (Note: the following numbers are hypothetical. They are for demonstration only)
    Number1 (Toxicity Limit) = 10mg/kg (For Human. not dogs, fish, plant, etc)
    Number2 (Base Ingestion) = 0.1mg/day (For Human)
    Number3 (Clearing Rate) = 1mg/day (For Human)
    Number4 (System Level) = 5mg/L (For City of Davis)
    Number5 (Natual Level) = 0.1mg/L (For City of Davis)

    Then for a human of 10kg, the person would get poisoned if 98.9mg is ingested per day from drinking water. This equates to drinking 19.78 liters of water.

    From these numbers, a guideline can be created like this:

    10kg -> Not safe to consume more than 19 L per day (79 cups of water)
    50kg -> Not safe to consume more than 98 L per day (396 cups of water)
    100kg -> Not safe to consume more than 197 L per day (791 cups of water)

    Each of us can see this result and determine for ourselves whether that water usage behavior is exceeds our foreseeable usage. Anyone who sees a situation where they would use that much water should inform the rest of us the situation. If no one can see a situation where Fluoridation would cause this type of harm, then no one can rationally object Fluoridation for [i]this[/i] reason.

    The same kind of quantitative analysis can be done for each concern. And everyone can see if any concern remains.

    If the proposed system level is too high, the acceptable level can be derived based on the reported usage levels. If collectively, the concerns drive the acceptable system level (Number4) to existing Fluoride concentration (Number5), then the system does not need Fluoridation. (If Number4 is driven below Number5, then the system needs [b]De-[/b]Fluoridation.)

    A decision method like this makes the decision less vulnerable to irrationality compared to having a direct vote where a voter does not need to disclose their rationale of objection.

  14. In the analysis above, I didn’t account for the Clearing Rate (Number3) correct. Using the same [b]hypothetical[/b] numbers, the safe level should be this instead:

    For a 10kg person, the person would be poisoned with 100mg of Fluoride is accumulated in their body. To avoid any daily accumulation, the total daily ingestion rate cannot exceed 1mg (Number3). Therefore, the safe daily ingestion amount of drinking water is 0.9mg/day, which is 0.18 Liters (less than 3/4 cups of water). If that person drinks 1 L/day, the Fluoride accumulation is 4.1mg/day. This means that the person will be poisoned in 24 days.

    Number3 is an important number and any rationale that claims Fluoride ingestion to be safe in certain context (short-term or long-term), should know how fast the human body can get rid of it.

  15. Matt

    [quote]A recent report from the U.S. National Research Council (NRC 2006) concluded that adverse effects of high fluoride concentrations in drinking water may be of concern and that additional research is warranted. Fluoride may cause neurotoxicity in laboratory animals, including effects on learning and memory … [/quote]

    I think that the question of when, or even if, future research in this area is warranted for the dosing levels that are being proposed in our area. One might notice when reading literature from both sides of the controversy that a phrase that occurs repeatedly is at ” high fluoride concentrations”. This is a critical point of consideration since there is no one that appears to feel that up to the level of 1mg/l represents a “high concentration”.

    Going back to the study design for the meta analysis of the comparative IQ studies, the authors point out that
    “such circumstances are difficult to find in industrialized countries because the fluoride concentrations in community water are usually no higher than 1 mg/L even when fluoride is added to water supplies as a public heath measure to reduce tooth decay. Multiple epidemiological studies of developmental fluoride neuortoxicity studies were conducted in China [b]because of the high fluoride concentratios that are substantiallly above the 1 mg/ L in well water in many rural communities.[/b] In other words, even these authors, specifically looking for an adverse neurologic outcome do not think that there is value in doing the study in areas of low fluoride
    content.

    I think this partially reflects your question about when follow up studies might be done because they were suggested by one group. At least in medicine, this caveat about more research being needed is a common
    “stock” statement made at the end of many research articles in which the authors have not found any definitive evidence to support their hypothesis, or feel that their results are suggestive, but not definitive.

    To decide whether such a recommendation for “more research” should be acted upon a couple of factors should be considered.
    1) Does the research have any relevance to the target population? In this case, I would be in agreement with
    the statement of the meta analysis authors that pursuing this area of research in a population not at risk,
    namely those exposed to low ( conservatively speaking < 1 mg/l will unlikely be productive. Researching it
    in China and Iran where exposure levels in some areas is very high makes a lot of sense. Researching it here
    is virtually certain to be non productive, and has already been negatively vetted as a research project by this
    group.
    2) Is there already evidence either of a clinical or epidemiologic nature than makes additional study
    unnecessary. I think this point has some relevance to this discussion. We have 65 years of experience with
    fluoridation in this country with no evidence to suggest that fluoride, in the levels found in drinking water
    has led to any change in IQ levels. One could argue whether or not comparative studies should have been
    done 65 years ago prior to starting the process. However, now we have 65 years worth of empiric evidence of
    safety at the proposed level.

  16. medwoman, from my perspective if the anti-fluoridation forces want the arguments they put forward to have weight, then they need to transform the words [i]”may be of concern and that additional research is warranted.”[/i] into the words [i]”is a proven concern because additional research was warranted and has been completed and has confirmed the concern to be valid at dosage levels relevant to (comparable to) the dosages being delivered.”[/i]

  17. The logic of accountability:

    Given a status quo and a lack of information regarding a concern, the entity that decides to change the status quo nonetheless is accountable for the issues if the concerns manifests into problems. On the other hand, the entity that decides to not change is accountable for issues that result from not changing.

    Suppose there is a bucket of water. John warns Mary not to drink it. Mary asks for evidence that the water is unsafe. John cannot provide the evidence.

    If Mary drinks the water and gets sick, John is not accountable for her sickness.

    If Mary forces John to drink the water and John got sick, Mary is accountable for the sickness.

    If John forces Mary not to drink the water and Mary gets sicker than she would have if she had drank the water, John is accountable for that difference.

    Because of this set of accountability, it is often easier to stick with the status quo, or have a solution where Mary gets to drink the water from the bucket without also forcing John to drink from it.

    This has nothing to do with “putting weight” to the argument. [b]Accountability itself has enough weight.[/b] There is no need to sway decision with “weight”.

  18. As one of the authors of Thursday’s articles, I agree that there are only associations between neurotoxicity, cancer, and other toxic problems with fluoride. And that is how we reported it. The only proven disease proven to be caused by fluoride is fluorosis of teeth. The CDC says that the incidence of mild to severe fluorsis in 12 to 15 year old teenagers is 41% in the US. Fluorosis is of significant enough concern that distinct warnings are issue to women NOT to use fluoridated water when mixing dry baby formula for incidence because of the proven link with fluorsis in erupting teeth if exposed to excess fluoride. I think all will agree that the causal link between excess fluoride and fluorosis is proven.

    The question to be carefully considered is what is the total amount of other fluorides ingested by humans drinking fluoridate water. There are many, many other sources of fluoride in the average human diets including bottled beverages and tea and pesticide laden foods. These all point to increased risks to humans which must be weighed against the efficacy of fluoridated water to reduce caries risk. We do not believe there is any substantial body of evidence proving that fluoridated water provides such a benefit and we will present such evidence in detail when the anti-fluoride presentation is made to the WAC in late May.

    If there is no proven benefit to water fluoridation and there are proven risks (fluorosis – particularly in infants) and unproven but associated risks (see above), then why not take the prudent approach and rely only fluoridated tootpastes, mouthwashes, lacquers to provide what has been clearly shown to be the topical benefits of fluoride on teeth.

    We DO NOT deny fluoride has a benficial impact on dental health but only when applied topically. We DO deny that caries prevention benefit is proven to be provided by drinking water. Let’s all subscribe to the most important guiding primciple in medicine – First, Do no harm!

    Matt has suggested that we should have to show that these other risks are proven. I suggest the burden of proof is on the fluoridation proponents. Prove that there are no risks to fluoridating water (including fluorosis)and then prove that fluoridation of drinking water is effective in caries prevention.

    If viewed in that light, there is no question that drinking water fluoridation DOES have some proven risks (fluorosis) and the entire body of evidence DOES NOT prove it has efficacy in preventing caries.

    Sorry I am on the road and cannot post references but many are posted on http://www.fluoridealert.org.

  19. [quote]Matt has suggested that we should have to show that these other risks are proven. I suggest the burden of proof is on the fluoridation proponents. Prove that there are no risks to fluoridating water (including fluorosis)and then prove that fluoridation of drinking water is effective in caries prevention.
    [/quote]

    Totally agree. Since it’s a foreign substance being added to our drinking water the burden is on those that want to add the chemical to prove it’s both beneficial and harmless [b]BEYOND A DOUBT[/b].

  20. I also note that the pro-fluoridation forces did not reference a single scientific study last Thursday that supportwed their claim that fluoridated drinking water prevented dental decay. Speaker after speaker simply stated that “…in my experience…trust me on this one”. I believe it would have been more appropriate if at least one single speaker had discussed recent evidence supporting their hypothesis that drinking water fluoridation reduces dental decay.

    I also thought that the speakers agrument that “informed consent” to medication was not necessary here because the dental community had already decided what was in the “greater public good”. Thank you but I and many others would prefer to make the determination that drinking water fluoridation is in our own best interests ourselves.

    I also find it hard to justify annually putting approximately 12 tons of fluoridated compounds into our water (at 0.7 ppm) when only 1% of that water is actually drunk by people. The rest is distributed throughout our environment and particularly deposited in our wetlands in the form of treated sewage discharge. I note that there has been absolutely no assesment of the environmental impacts of such cumulative discharges. Where is the CEQA analysis of this?

  21. Alan, I realize that 1) Wikipedia is far from a definitive source, and 2) what I am about to say will be considered to be semantics, but assigning fluorosis the label of “disease” is a bit much don’t you think? Wikipedia calls fluorosis a “developmental disturbance.” Merriam-Webster defines fluorosis as “an abnormal condition (as mottling of the teeth) caused by fluorine or its compounds.” Virtually all the medical dictionaries refer to fluorosis as a “condition.” Two refer to it as “Chronic fluorine poisoning.” All the medical definitions use (in one form or another) the words “excessive amount of fluorine.”

    Do you agree that individuals have the ability to minimize the risk of incidence of fluorosis?

  22. In terms of accountability, the responsibility in fact-finding is well-defined self-regulated process, resulting in a natural “division of labor” and collaboration.

    People who wants fluoridation should focus on researching about its risks, because they are accountable for the damages of that decision. If they don’t know enough about the risk to [b]stop themselves[/b] from making the decision, they will hurt their own accounts.

    Similarly, people who do not want fluoridation should focus on researching about the risks of not doing so because if they don’t know enough about the risks, they will just be hurting their own accounts.

    The result is that both side will do the research to keep themselves from making bad decisions. Neither side need to convince the other side anything.

    The situation we have right now comes from the incorrect implementation of accountability of our decision method: 1) That everyone collectively can only make one decision; 2) That no one is accountable for their ignorance.

    A decision process that makes sense for an individual (weighing the pros and cons then make a decision), is not directly applicable in the context of a group of individuals, because there is no dogmatic reason that the group as a whole can only have one behavior pattern. That is an incorrect scaling of a decision method with no consideration of emergent properties.

    The understanding of these differences should be learned before people graduate from high school. Because people need to know this to understand commonality and variability analyze for proposed policies so that they can reject policies that forces commonality, creating conflict, when it can be varied resulting in no conflict.

  23. So the F in our water is the culprit. Its not the teachers that are causing the schools of America to fail its the SnF in our toothpaste wasting the cognitive skills of our youth! After 50 years don’t you think we would be able to find this link if it existed? Wouldn’t all this scrutiny have revealed it by now in multiple studies? What about identical twins raised on and off SnF?

    I always love this sort of nonsense. Remember LSD was going to cause birth defects. Where are all those defective hippie children anyway?

  24. [i]”Matt has suggested that we should have to show that these other risks are proven. I suggest the burden of proof is on the fluoridation proponents. Prove that there are no risks to fluoridating water (including fluorosis)and then prove that fluoridation of drinking water is effective in caries prevention.”[/i]

    Alan I started this WAC process by going back to ground zero and looking at the wealth of evidence that has been provided by the scientific community regarding fluoridation of water since it began 75 or so years ago. There is no shortage of peer-reviewed published research articles cataloguing the benefits of fluoridation. On the other hand, the number of peer-reviewed published research articles questioning the efficacy of fluoridation is very small by comparison.

    When I read the [i]Scientific American[/i] article Barbara King gave me at the Farmers Market, I had no trouble agreeing with the National Research Council (NRC) conclusion that adverse effects of [u]high fluoride concentrations in drinking water may be of concern[/u] and that [u]additional research is warranted[/u]. Let’s 1) engage that conclusion and 2) throw away all the research published prior to 2006 and 3) engage your comment about “burden of proof.” The easy way to do that is to ask, [i]”Since 2006 when the NRC report was published what further research has been completed?”[/i]

    At the state level, California Office of Environmental Health Hazard Assessment (OEHHA) and the California Immunization Coalition (CIC) took testimony in October, 2011 and decided not to place fluoride on the California Prop 65 list. At the federal level, the Centers for Disease Control and Prevention (CDC) continues to monitor and review community water fluoridation and has stated it’s continued support as recently as October 2012. CDC researcher S.O. Griffin published [url]http://www.wda.org/wp-content/uploads/2012/05/Effectiveness-Fluoride-Preventing-Cavities.pdf[/url] in 2006. In 2012 “Effects of Fluoridated Drinking Water on Dental Caries in Australian Adults” was published (see [url]http://www.ada.org.au/app_cmslib/media/lib/1303/m537918_v1_nsaoh fluoridation paper.pdf[/url] and in March 2013 the 2012 Austrailian research got some weighty concurrance (see [url]http://www.fluoridesandhealth.ie/documents/Harvard-Med-Dental-School-Deans-March2013.pdf[/url] as follows: “[i]As Deans of Harvard Medical School and the Harvard School of Dental Medicine, we continue to support community water fluoridation as an effective and safe public health measure for people of all ages. Fluoridation has made an enormous impact on improving the oral health of the American people … we continue to support community water fluoridation as an effective and safe public health measure for people of all ages. Numerous reputable studies over the years have consistently demonstrated that community water fluoridation is safe, effective, and practical. Fluoridation has made an enormous impact on improving the oral health of the American people.[/i]

    During that same timeframe, how has the opposition to fluoridation addressed the gauntlet that the NRC threw down in 2006?

  25. [quote]During that same timeframe, how has the opposition to fluoridation addressed the gauntlet that the NRC threw down in 2006?[/quote]

    Matt – Try turning the question around – how have the proponents of fluoridation addressed the gaunlet the NRC threw down in 2006?

    I would suggest the burden of proof is on the providers of what is otherwise characterized as a hazardous waste to prove it is effective and safe. All you have offered is summary quotations by “experts” that it is safe but they have not referenced any recent scientific evidence that addressed the very serious concerns raised in the NRC report.

    I would suggest you view several videos prepared by Fluoride Action Network that address the questions of safety and efficacy. I do not believe after viewing these videos that you will remain a skeptic that there are no appreciable health risks to fluoridation and you will come away very skeptical about the efficacy of fluoridation.

    Professional Perspectives (including interviews with a number of NRC paneists) – http://www.fluoridealert.org/fan-tv/prof-perspectives/

    10 Facts about Fluoride – http://www.fluoridealert.org/fan-tv/10-facts/

    A Pediatricians View of Fluoride – http://www.fluoridealert.org/fan-tv/dr-whyte/

    While you are at the FAN-tv website, also browse and view some of the debate videos available. They are all informative and done quite well.

    I would otherwise say is easy to grab summary quotes by “knowledgeable experts” about the safety and efficacy of fluoride just as the “experts” all told us DDT was safe when they sprayed it in classrooms and along streets of entire communities of minority and disadvantaged people up until the 1960s. This was all under the guise of it was “safe” and “good” for them. The truth of DDT toxicity was suppresed and did not come out until much later.

    P.S. They used to spray DDT at the Catholic School I attended in the San Joaquin Valley as a child in the 1950s. They told us it was to get rid of all the lice problems we had at the school and to prevent mosquitos from breeding (control of flooding and standing water was much less effective then in the Valley). All I remember about it is it stunk like hell for a week when they were done. Of course, I admit that I am still alive…but still!

    By the way, the government of Queensland (Australia) recently ended mandatory fluoridation as did the Ontario provincial government and Israel.

  26. For the rationale regarding the benefit on dental health, what is the reason for fluoridation of the water supply, instead of, say, mouth rinse?

    If a household only drinks 10% of the water it consumes and only 10% of that drank water is effective in affecting dental health, then the system is wasting 99% of the fluoridation (material cost and operation cost). That is a 100 times overpayment to the entity doing the fluoridation.
    (Imagine your paycheck becomes 100 times bigger.)

    We already know how much a bottle of mouth rinse would cost off the shelf. The pro-fluoridation people also claim to know how much fluoridation would save people. Then it seems that it would make business sense for the City to manufacture a “City of Davis” brand mouth rinse that is cheaper than commercial products, and the cost of the business would pay for itself by people in the city would would buy that product. To reduce packaging cost, people can simply bring their own bottle and fill it up.

    If this does not make business sense, the claim that fluoridating the water supply could save dental cost would collapse on its own.

  27. In such an enterprise, whoever wants city-created fluoride mouth rinse can simply invest their own money and become a shareholder.

    If you think that it will sell, you would rush to make an investment. The role of the City is to make sure that everyone has a fair chance to get a share of the enterprise, and only distribute/sell the shares when the anti-fluoridation people forfeit their rights to join the enterprise.

    No one takes extra risk. Everyone gets a benefit proportional to their investment. No conflict.

  28. alanpryor said . . .

    [i]”Matt – Try turning the question around – how have the proponents of fluoridation addressed the gaunlet the NRC threw down in 2006? “[/i]

    Alan, I did that in the prior post. Here it is again.

    At the state level, California Office of Environmental Health Hazard Assessment (OEHHA) and the California Immunization Coalition (CIC) took testimony in October, 2011 and decided not to place fluoride on the California Prop 65 list.

    At the federal level, the Centers for Disease Control and Prevention (CDC) continues to monitor and review community water fluoridation and has stated it’s continued support as recently as October 2012. CDC researcher S.O. Griffin published “Effectiveness of Fluoride in Preventing Caries in Adults” (see [url]http://www.wda.org/wp-content/uploads/2012/05/Effectiveness-Fluoride-Preventing-Cavities.pdf[/url]) in 2006. In 2012 “Effects of Fluoridated Drinking Water on Dental Caries in Australian Adults” was published (see [url]http://www.ada.org.au/app_cmslib/media/lib/1303/m537918_v1_nsaoh fluoridation paper.pdf[/url]) and in March 2013 the 2012 Austrailian research got some weighty concurrance (see [url]http://www.fluoridesandhealth.ie/documents/Harvard-Med-Dental-School-Deans-March2013.pdf[/url] as follows: [i]”As Deans of Harvard Medical School and the Harvard School of Dental Medicine, we continue to support community water fluoridation as an effective and safe public health measure for people of all ages. Fluoridation has made an enormous impact on improving the oral health of the American people … we continue to support community water fluoridation as an effective and safe public health measure for people of all ages. Numerous reputable studies over the years have consistently demonstrated that community water fluoridation is safe, effective, and practical. Fluoridation has made an enormous impact on improving the oral health of the American people.”[/i]

  29. alanpryor said . . .

    [i]”I do not believe after viewing these videos that you will remain a skeptic that there are no appreciable health risks to fluoridation and you will come away very skeptical about the efficacy of fluoridation.”[/i]

    Alan, I would certainly not characterize myself as a skeptic. I will watch the video and get back to you.

    Regarding your comment [i]”All you have offered is summary quotations by “experts” that it is safe but they have not referenced any recent scientific evidence that addressed the very serious concerns raised in the NRC report.”[/i] what is it that you discount about either the [u]Effectiveness of Fluoride in Preventing Caries in Adults[/u] paper by the CDC or the [u]Effects of Fluoridated Drinking Water on Dental Caries in Australian Adults[/u] paper by the team from the University of North Carolina at Chapel Hill, and the Australian Research Centre for Population Oral Health, The University of Adelaide? As best as I can tell neither are summary quotations, both are research studies.

  30. Growth Izzue said . . .

    [i]”Totally agree. [b]Since it’s a foreign substance being added to our drinking water[/b] the burden is on those that want to add the chemical to prove it’s both beneficial and harmless BEYOND A DOUBT.[/i]

    GI, you need to check your facts. Fluorine is a naturally occurring substance in waters throughout the World. The current level in Davis well water from Davis’ current 26 wells is as low as 0.1 and as high as 0.36. I can tell you with 100% certainty BEYOND A DOUBT that you have suffered no adverse effects from that “foreign substance.”

  31. Many of the opponents of fluoridation cite the NRC 2006 report. It should be remembered that the NRC was charged with a review of the EPA’s standards of 2-4 mg/l – NOT the usual amounts found in municipal drinking systems – 0.7-1.2 mg/l. Here is what the NRC report says: [quote]The committee’s conclusions regarding the potential for adverse effects from fluoride at 2 to 4 mg/L in drinking water do not address the lower exposures commonly experienced by most U.S. citizens. Fluoridation is widely practiced in the United States to protect against the development of dental caries; fluoride is added to public water supplies at 0.7 to 1.2 mg/L. The charge to the committee did not include an examination of the benefits and risks that might occur at these lower concentrations of fluoride in drinking water. (NRC, 2006, Executive Summary, page 11, accessed from:http://www.nap.edu/catalog.php?record_id=11571 [/quote]

    The NRC report is very careful to say that its research recommendations are limited to those for fluoride levels in drinking water of between 2-4 mg/l.

  32. [quote]I agree that there are only associations between neurotoxicity, cancer, and other toxic problems with fluoride.[/quote]

    I agree that this is the assertion that you have made. I find it a little disingenuous however to keep repeating speculative “associations” for which there is no support. I would like to go back to my Tylenol analogy.
    If I were to repeat over and over that Tylenol is associated with liver failure in order to prevent someone from taking two Tylenol by scaring them, would you feel I were being completely honest ?

  33. Re: rdcanning

    Do you happen to know what ingestion rate and body weight the NRC 2006 report is using to make the conclusion that 1.2mg/L is ok, but 2mg/L is not?

    These numbers mean that even at 1.2mg/L, if a person drinks two times as much water the person will be not okay.

    If that conclusion is based on a 50kg person who drinks 2L every day, it means that the “unsafe” level is 0.067mg/kg. So it is unsafe for a 10kg infant to ingest 0.67mg of Fluoride daily. For the proposed concentration of 0.7mg/L, it means that it is unsafe for an infant to drink 4 cups day.

    According to Matt’s number on the current Fluoride concentration of wells (0.1mg/L to 0.36mg/L), current an infant would have to drink 8 cups a day to be “unsafe”.

    Do you happen to know the actual body weight and intake rate used in that NRC 2006 study? That would save me time from reading it.

  34. Edgar, the NRC report does not report specific levels of ingestion. Their charge was to review the risks and benefits of 2-4mg/l of fluoride in drinking water. I included a link to the website where you can download the executive summary. You can even download the full 500+ page report there.

  35. GI

    I am sorry for the delayed response with regard to your citation of the article on the effect of fluoride on thyroid function. Again, this is one of those areas where there “may be an association” but for which there is no
    conclusive evidence, and for which the suggestion of an association is not implicated for the level of 0.7 mg/ L
    but rather for values of 2 – 4 mg / L. This is backed by the findings of the NRC report cited by rdcanning.
    However, for the sake of completeness, I will consult with my endocrinology consultants on this issue and can get back with you within the next few days.

  36. Re: rdcanning

    It is on Page 29 ([url]http://www.nap.edu/openbook.php?record_id=11571&page=29[/url])

    A typical person is assumed to drink 1 L of water daily. A “High” consumer drinks about 2 L of water daily. A typical adult is 70kg. The intake estimates are provided for each age group. An “Infant” is 8.33kg.

    In the NRC report, it is recommended to lower the 4mg/L level (MCLG), which corresponds to health risk. The 2mg/L level (SMCL) corresponds to comestic risk associated with dental fluorosis. Page 10] ([url]http://www.nap.edu/openbook.php?record_id=11571&page=10[/url])

    These limits are set when there is enough evidence to substantiate the risk. When it is not set lower, it does not mean that lower is “safe”, it means that there is no evidence, or not enough studies done to get the evidence to lower it further. There was no recommendation to lower the SMCL because NRC didn’t know how to assess/quantify psychological and social damage due to cosmetic damage (15% of children to have discoloration of front teeth from fluorosis).

    Number1 (Safety Limit):
    o Neurological damage: 0.06mg/kg/day
    o Cosmetic damage: 0.03mg/kg/day

    Number2 (Base intake from sources other than drinking water):
    o 0.03mg/kg/day (Page 23) ([url]http://www.nap.edu/openbook.php?record_id=11571&page=23[/url])

    Number3 (Excretion Rate):
    o Adult: 50% (with healthy kidneys). The rest accumulates in bones and teeth.
    o Infant: 20%. The rest accumulates in bones and teeth. (FAN) ([url]http://www.fluoridealert.org/articles/50-reasons/[/url])

    Number4 (Proposed system concentration):
    o 0.7 mg/L

    Number5 (Current system concentration):
    o 0.1mg/L to 0.36 mg/L

    Current Unsafe Drinking Amount:
    (Drink no more than…)
    o Neurological Risk:
    o .. Infant (8.33kg) -> 2.9 cups
    o .. Adult (70kg) -> 14.8 cups
    o Cosmetic Risk:
    o .. Infant -> 1.5 cups
    o .. Adult -> 7.4 cups

    Unsafe Drinking Amount with 0.7mg/L fluoridation:
    o Neurological Risk:
    o .. Infant -> 2.1 cups
    o .. Adult -> 12.9 cups
    o Cosmetic Risk:
    o .. Infant -> 1.0 cup
    o .. Adult -> 6.4 cups

    Unsafe Drinking Amount with 4.0mg/L fluoridation:
    o Neurological Risk:
    o .. Infant -> 0.6 cups
    o .. Adult -> 5.7 cups
    o Cosmetic Risk:
    o .. Infant -> 0.3 cups
    o .. Adult -> 2.8 cups

  37. Edgar

    [quote]According to another thread, toxicity effect depends on body weight. Assuming that this relation is linear, a baby of 10kg is 4 times as vulnerable to a child of 40kg. [/quote]

    I am sorry for not responding to your comments yesterday.
    I truly appreciate your efforts to quantitate the risk to the individual. With regard to this approach, a couple of limitations should be noted.

    The first is that the statement “toxicity effect depends on body weight” would more accurately state
    “toxicity depends in part upon body weight ” thereby acknowledging the complexity of biological systems.

    Next is the assumption that “this relation is linear”. Unfortunately, such an assumption is rarely applicable to
    complex biologic systems. While I saw that you attempted to make a correction doubtless thereby making a more valid statement by considering renal clearance, there are still a number of factors that cannot be accounted for to provide an accurate level of individual risk:

    1) The age of the individual – stage of development frequently makes a huge difference in whether or not there
    will be any beneficial or adverse effects from a given exposure or intervention. As I have previously stated,
    despite approximately 65 years of presence of fluoride in the American water supply at levels of less than
    1 ppm, fluoride remains a Category B substance in pregnancy meaning that there are no studies which
    demonstrate harm to the developing fetus at this level.
    2) The presence of alternative body processes to deal with “excess” of a substance – in the case of fluoride,
    what the kidneys do not clear is largely sequestered in bone. However, this is not permanent storage. The
    system is dynamic such that at times of decreased fluoride ingestion the fluoride will exit the bone, enter the
    circulation and thus be subject to renal clearance again.
    3) Gender based differences – this might be another area for potential researcher in areas of naturally
    occurring high levels of fluoride in the water supply. It is unlikely to be a useful area for research in this
    country for exactly the same reason as given by the Harvard meta analysis authors, there is simply no
    evidence to support the “association” of fluoride with harm at the level of or lower than 1 ppm.

  38. Re: Medwoman

    I created a table that does not contradict the 3 points you made.
    [How much is too much?] ([url]http://skylet.net/docs/2013-04-28_-_Fluoridation.htm[/url]) – How many cups of water a person needs to drink to reach the risk level.

  39. Edgar

    The table that you created does not contradict my points, it simply does not take them into account.
    Because of individual variability, I do not believe that there is a given quantity of water that one can designate
    based on only your listed parameters that will apply to different individuals equally.

    Let me use an example using another common substance, alcohol.
    My partner and I are the same height and essentially the same weight. He is male, I am female. He has no difficulty consuming two glasses of wine without demonstrating any signs of impairment regardless of whether or not he has eaten. I am unable to drink an entire glass of wine of the same size without starting to get giddy
    and sometimes even to slur my words if I have not eaten dinner at the same time.
    So, we are essentially the same body mass and yet due to differences in body composition, absorption rates, metabolic rates, rates of enzymatic breakdown, interaction with other body systems ( digestion), possibly hormonal influences, and I am sure a host of factors of which I am not aware, we will not have the same risks associated with the consumption of the same amount of liquid.

    I believe that this also holds true for fluoride. However, this does not mean that there is no level at which there is no demonstrated harm. For instance if one were to take a single drop of alcohol neither my partner nor I, nor a baby would experience any adverse consequence. So the issue becomes, is there a level of fluoride in the water which has been demonstrated over time to be safe ? My belief is that over the past 65 years in this country, there is enough evidence to demonstrate that ( with the possible exception of mild fluorosis) there has been no demonstrated harm from a level of 1ppm or less in the drinking water to be able to site this as a safe standard.