Fluoride debate: Why I support fluoridation – Response from Connett

This is Paul Connett’s response to Ken Perrott’s article – Fluoride debate: Why I support fluoridation.


I think your opening statement certainly gives us a perspective from where you are coming on this issue Ken and that is helpful.

I am very glad that you put “having an open mind” and “relying on science” as your key tools for resolving controversial issues like fluoridation. I believe that once you have got over some negative impressions that you have had with some people opposed to fluoridation, that you will find that having an open mind and relying on the best science will inevitably lead you to rejecting fluoridation and to see it as the misguided practice it is. But we shall see.

As far as the case you present I find it very, very short on science. Basically you argue that fluoride is needed to react with our bio-apatites and make them stronger, less soluble and in the case of teeth less vulnerable to tooth decay. You offer no scientific evidence that interaction with the bones is beneficial and can be achieved without damage to the bone or the connective tissue.

Your case as far as the teeth are concerned seems to boil down to the need to put fluoride in the drinking water so after passing through the whole body it ends up in our saliva and that this is the delivery system which reduces tooth decay. Two questions: 1) Why do you feel that this is more rational and suitable than treating the tooth enamel more directly with topical treatments like fluoridated toothpaste?  2) If you reject topical treatment for some reason and you insist the fluoride must be swallowed to be effective why don’t you use a more appropriate way of delivering fluoridated water, i.e. in one liter bottles at 1 ppm and prepared with pharmaceutical grade sodium fluoride?

I asked this latter question at the end of section 1A but in your response you did not answer. So may I ask it again?  Would not this delivery system provide, 1) a better control of the dose, 2) a far better control over the purity of the chemical used and 3) would not force this human treatment on people who don’t want it. Nor would it involve giving up on the central dogma of water fluoridation. Surely this would be a win-win situation for everyone?

On the ethical front, you stress the need to help disadvantaged children. No argument there from me. But what if your chosen method actually further disadvantages these children and their families? What for example are parents in low-income families supposed to do if they don’t want their children to drink fluoridated water? Haven’t you trapped these families with this policy? Moreover, are you not aware of the extensive literature from India that fluoride’s toxic effects are more serious for people with poor nutrition (low protein, low vitamins and low calcium – see the early work from Pandit et al., 1940 and the more recent animal studies from Chinoy, NJ – see the FAN bibliography for full citations, http://fluoridealert.org/researchers/fan-bibliography/)? Aren’t children in disadvantaged communities more likely to have poor nutrition?

Scotland, which has no fluoridation, has found a simple and cost-effective alternative way of fighting tooth decay as this recent BBC Scotland report indicates ( http://fluoridealert.org/news/nursery-toothbrushing-saves-6m-in-dental-costs/):

 “A scheme to encourage nursery children to brush their teeth has saved more than £6m in dental costs, according to a new study.

Childsmile involves staff at all Scottish nurseries offering free supervised toothbrushing every day.

Glasgow researchers found that the scheme had reduced the cost of treating dental disease in five-year-olds by more than half between 2001 and 2010.

The programme was launched in 2001 and costs about £1.8m a year.

It emphasises the importance of toothbrushing and helps parents establish a healthy diet from the earliest stage.

A number of nurseries and schools in targeted areas also provide fluoride varnish and toothbrushing in primary one and two.

An evaluation, funded by the Scottish government and carried out by Glasgow University, found that fewer children needed dental extractions, fillings or general anaesthetics as a result of the programme.

‘Less toothache’

There was also said to be a drop in the number of children needing hospital treatment for dental problems, freeing up operating theatres.

Public Health Minister Michael Matheson said: “This is an amazing achievement and shows just how much can be saved from a very simple health intervention.

“This has seen less tooth decay in children which means less toothache, fewer sleepless nights and less time off school.

“By this simple measure, NHS costs associated with the dental disease of five-year-old children have decreased dramatically.

“More children can just be treated routinely in the dental chair because they need less invasive treatments, so fewer fillings and fewer extractions, and many more children with much better oral health than we have seen in many years.”

For the second time you state your concerns about, “Unwarranted extrapolation from studies done at high concentration” which you say are “a dime a dozen and worthless in this debate.”

Last time you brought this up I responded by showing that several human IQ studies were not done at high concentrations. For example, in nine of the 27 IQ studies  reviewed by Choi et al (2012), the high fluoride village was at 3 ppm or less. I also went into more detail on the study by Xiang et al. (2003a,b) who found a threshold at 1.9 ppm for this effect.

In my discussion on this point I stressed the difference between concentration and dose and the need to consider a margin of safety calculation to protect for the full range of expected sensitivity or vulnerability in a large population when extrapolating from a small human study of a fairly homogeneous population. Thus extrapolating from Xiang’s study we find that there is absolutely no margin of safety to protect either for the range of exposure to fluoride in an American or NZ population or for the full range of sensitivity expected in any large heterogeneous population. This latter calculation is particularly important for your major concern – disadvantaged children – because that is almost certainly where you will find the most vulnerable in this regard.

When we embarked on this exercise I thought that this was going to be an exchange between yourself and me, but I am finding that you do not want to restrict yourself to my arguments but want to argue against all the arguments thrown at you by people opposed to fluoridation. That has a place of course but it was not what I was expecting. In my view it serves to distract and muddy the waters.

I wish you had taken a more disciplined approach and focused entirely on the arguments I have put forward. In this respect it is unfortunate that when you were educating yourself on this issue you did not take advantage of reading the book I co-authored with two other scientists, James Beck, MD, PhD and Spedding Micklem, DPhil (Oxon). There we spelled out the case in a cool, calm and collected way with every argument backed up with citations to the scientific literature. As you know – but your readers may not – I sent you a pdf copy of this text. By so doing, I had hoped that we could keep this debate tightly focused; that I could defend my own arguments (and there is plenty enough of those) and not have to keep considering those of others.

Your readers might also not know that shortly after this book was published (Oct 2010) I was invited in early 2011 to meet with staff of the Ministry of Health in Wellington. About 20 people were there from the Ministry and some of their advisers. I carefully went through the arguments in the book and asked them at the end of my presentation to provide a written response to the book showing where I was wrong and providing the science that supported their critique. I added that if they could not do this with all the resources and personnel at their disposal then they should not continue to promote this practice. After nearly 3 years I still have not received that written critique.  Meanwhile, personnel from this Ministry, including the Minister himself, continue to promote the practice and even accuse opponents of distorting the scientific arguments – with no specific examples to which someone like myself could respond.

Blanket condemnation of opponents gets us nowhere. Nor does it help to keep knocking down straw dummies. The debate will only be seriously engaged when the proponents begin to put forward and defend the studies that have convinced them that fluoridation is both effective and safe – and safe for everyone. This is what opponents like myself have done. This was what I was expecting from you Ken when you got the opportunity to put forward your case. Surprisingly, you gave no scientific citations at all.  Hopefully, these will come later.

Rather than take up any more space at this point I will wait for part 2 of your case, where I hope you will present some science to support this practice.

While you are doing this I will prepare my response to your response to my section 1A.

References

Choi et al., 2012. Developmental fluoride neurotoxicity: a systematic review and meta-analysis. Environ Health Perspect 120:1362–1368.

Pandit et al., 1940, Endemic Fluorosis in South India, Indian Journal of Medical Research 28, no. 2: 533–58.

Q. Xiang, Y. Liang, L. Chen, et al., “Effect of Fluoride in Drinking Water on Children’s Intelligence,” Fluoride 36, no. 2 (2003): 84–94, http://www.fluorideresearch.org/362/files/FJ2003_v36_n2_p84-94.pdf .

Q. Xiang, Y. Liang, M. Zhou, and H. Zang, “Blood Lead of Children in Wamiao-Xinhuai Intelligence Study” (letter), Fluoride 36, no. 3 (2003):198–99, http://www.fluorideresearch.org/363/files/FJ2003_v36_n3_p198-199.pdf .


Anyone wanting to follow the debate and/or check back over previous articles in the debate can find the list of articles at Fluoride Debate.

See also:

Similar articles on fluoridation
Making sense of fluoride Facebook page

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20 responses to “Fluoride debate: Why I support fluoridation – Response from Connett

  1. I love the reference to India, where they have to remove fluoride from groundwater because it is at unsafe levels! The complete ignorance!

  2. What is complete ignorance? Can you fill us in who are new to the topic Matt?

  3. Kurt Ferre DDS, Portland, OR USA

    Bravo to the early intervention program that has been implemented in Scotland for young children. It sounds like the very programs like Head Start that exist in my home town of Portland, OR, the largest city in the U.S. without fluoridation. The sad fact that Dr. Connett ignores is that Head Start begins at 3 years old (what about the earlier years?), and the fact that fluoridation is for everyone, not just children.
    My immigrant grandparents had dentures, my parents had partial dentures, and my 5 siblings and I have all our teeth except our 3rd molars. All of us are “Baby Boomers”, and 7 out of 10 of the most commonly prescribed prescription meds cause xerostomia or dry mouth. With a reduction of saliva, the risk for cavities on the root surfaces increases. Fluoridation reaches ALL members of society, and it will help protect the root surfaces of adult teeth.
    http://www.ncbi.n
    J Am Dent Assoc. 1990 Feb;120(2):143-9.
    Adult root caries survey of two similar communities with contrasting natural water fluoride levels.
    Stamm JW, Banting DW, Imrey PB.
    University of North Carolina, School of Denistry, Chapel Hill 27599-7455.
    http://www.ncbi.n
    J Appl Oral Sci. 2008 Jan-Feb;16(1):70-4.
    Root caries in areas with and without fluoridated water at the Southeast region of São Paulo State, Brazil.
    Rihs LB, de Sousa Mda L, Wada RS.
    Department of Community Dentistry, Dental School of Piracicaba, State University of Campinas, SP, Brazil.
    http://www.ncbi.n
    Am J Dent. 1994 Oct;7(5):271-4.
    Fluoride, remineralization and root caries.
    Featherstone JD.
    Department of Oral Sciences, Eastman Dental Center, Rochester, New York.
    http://www.ncbi.n
    J Dent Res. 1986 Sep;65(9):1154-8.
    Root caries in an optimally fluoridated and a high-fluoride community.
    Burt BA, Ismail AI, Eklund SA.
    http://www.ncbi.n
    Public Health Dent. 1989 Summer;49(3):138-41.
    Effect of residence in a fluoridated community on the incidence of coronal and root caries in an older adult population.
    Hunt RJ, Eldredge JB, Beck JD.
    Department of Dental Hygiene College of Dentistry, University of Iowa, Iowa City 52242.
    http://www.ncbi.n
    Gerodontics. 1986 Dec;2(6):203-7.

    The second issue I wish to comment on is the issue of bone health. On Dr. Connett’s FAN website, his reason #29 out of 50 reasons to oppose fluoridation references the Li study. Dr. Connett states that as the concentration of fluoride in the water increases from 1 ppm to 8 ppm, the rate of bone fracture increases. He is correct in this statement, but what he doesn’t tell you from the same the is what happens when the concentration goes from 0 ppm to 1 ppm.

    What Li’s study showed is that the rate of fracture actually decreases as the concentration of fluoride increases from 0 ppm to 1 ppm. The LOWEST rate of fracture is that found at optimal levels of fluoridation, and rate of fracture at 0 ppm is the SAME as that at 8 ppm.

    Intentional deception ?? You be the judge.

    The 3rd issue I wish to address is IQ. Having just returned from a 10-day tour of China, where my tour bus drove by many coal-burning electrical-generating plants with smoke billowing out from what looked like nuclear reactors, Dr. Connett is comparing apples to oranges. I still have a bit of a “China cough”, and on most days, one could cut the air with a knife. It stunk badly too. 1.4 billion people !! I visited 3 cities: Beijing (21 million), then, Xian (only 7.5 million), and finally, Shanghai (25 million). I’m very glad to be home.

    Harvard, Columbia, Georgetown, Duke, U. of Michigan, U. of Wisconsin, Vanderbilt, U. of Minnesota, USC, UCLA, Stanford, UC-Berkeley, U. of Washington.
    What do all these fine universities have in common? They are all located in fluoridated communities.
    The idea that the citizens in each of these communities, including the professors and their families that live there have lower IQ’s than in non-fluoridated communities is ludicrous.
    Convince me, anti’s, that the similar demographics in 50+ years fluoridated Corvallis, OR are dumber than their counterparts in non-fluoridated Eugene, OR.
    Even Dr.Connett’s Fluoride Action Network’s world headquarters in Burlington, VT. enjoys the public health benefit of fluoridation.

    Last but not least, the issue of Pharmaceutical vs. Water-quality grade fluoride additives. Dr. Connett loves to throw in the word, “industrial” to scare the public. From the CDC website explaining this issue:

    United States Pharmacopeia (USP) Grade Fluoride Products:
    Some have suggested that pharmaceutical grade fluoride additives should be used for water fluoridation. Pharmaceutical grading standards used in formulating prescription drugs are not appropriate for water fluoridation additives. If applied, those standards could actually increase the amount of impurities as allowed by AWWA and NSF/ANSI in drinking water.

    The U.S. Pharmacopeia-National Formulary (USP-NF) presents monographs on tests and acceptance criteria for substances and ingredients by manufacturers for pharmaceuticals. The USP 29 NF–24 monograph on sodium fluoride provides no independent monitoring or quality assurance testing. That leaves the manufacturer with the responsibility of quality assurance and reporting. Some potential impurities have no restrictions by the USP including arsenic, some heavy metals regulated by the U.S. EPA, and radionuclides.

    The USP does not provide specific protection levels for individual contaminants, but tries to establish a relative maximum exposure level of a group of related contaminants. The USP does not include acceptance criteria for fluorosilicic acid or sodium fluorosilicate.

    Given the volumes of chemicals used in water fluoridation, a pharmaceutical grade of sodium fluoride for fluoridation could potentially contain much higher levels of arsenic, radionuclides, and regulated heavy metals than a NSF/ANSI Standard 60-certified product.

    AWWA-grade sodium fluoride is preferred over USP-grade sodium fluoride for use in water treatment facilities because the granular AWWA product is less likely to result in dusting exposure of water plant operators than the more powder-like USP-grade sodium fluoride.
    http://www.cdc.gov/fluoridation/factsheets/engineering/wfadditives.htm#a1

    Fluoridation is a 20th Century adaptation of a naturally occurring process. Bravo to New Zealand, a country that I have visited twice to have brought fluoridation to the majority of citizens of your fine country. Those who choose not to drink the public water have the freedom to drink bottled water. We have machines at local grocery stores where one can bring their own jugs and fill them with RO water for $.42/gallon USD.

  4. Ok, Paul continues to ignore the science which has been repeatedly demonstrated to him.

    First, once again, the benefit of water fluoridation is in providing a consistent exposure of the teeth to low concentrations of fluoride throughout the day. Topical applications from high fluoride content toothpaste or other single exposures are certainly valuable, but do not offer the protection of consistent, regular exposure of the teeth to low concentration of fluoride. This occurs both topically and systemically.

    From the CDC:

    “Both drinking water and toothpaste provide important and complementary benefits. The drinking water provides long low-level protection, but the fluoride in toothpaste is at a high enough concentration that it has additional properties. Whether in water or toothpaste, fluoride works in two main ways: by slowing the activity of bacteria that cause decay, and by combining with the enamel on the surface of the teeth to make it stronger and more resistant to decay. Fluoride in the water, although at a lower concentration than in toothpaste, maintains a constant low level of fluoride in the dental plaque and saliva all day. Toothpaste provides a high level of fluoride, but only for 1-2 hours after brushing, so the water exposure during the remainder of the day takes over after that.”

    ——http://www.cdc.gov/fluoridation/fact_sheets/cwf_qa.htm#3

    Next, his idea of providing one liter bottles of 1ppm fluoride is ridiculous and defeats the whole purpose of the public health initiative, not to mention being far more expensive than fluoridating an entire system.

    Also which has been made clear to Paul, “pharmaceutical grade” fluoride is NOT preferable to HFA for fluoridation, and can actually be higher in concentrations of heavy metal contaminants than HFA.

    “Some have suggested that pharmaceutical grade fluoride additives should be used for water fluoridation. Pharmaceutical grading standards used in formulating prescription drugs are not appropriate for water fluoridation additives. If applied, those standards could actually increase the amount of impurities as allowed by AWWA and NSF/ANSI in drinking water.

    The U.S. Pharmacopeia-National Formulary (USP-NF) presents monographs on tests and acceptance criteria for substances and ingredients by manufacturers for pharmaceuticals. The USP 29 NF–24 monograph on sodium fluoride provides no independent monitoring or quality assurance testing. That leaves the manufacturer with the responsibility of quality assurance and reporting. Some potential impurities have no restrictions by the USP including arsenic, some heavy metals regulated by the U.S. EPA, and radionuclides.

    The USP does not provide specific protection levels for individual contaminants, but tries to establish a relative maximum exposure level of a group of related contaminants. The USP does not include acceptance criteria for fluorosilicic acid or sodium fluorosilicate.

    Given the volumes of chemicals used in water fluoridation, a pharmaceutical grade of sodium fluoride for fluoridation could potentially contain much higher levels of arsenic, radionuclides, and regulated heavy metals than a NSF/ANSI Standard 60-certified product.

    AWWA-grade sodium fluoride is preferred over USP-grade sodium fluoride for use in water treatment facilities because the granular AWWA product is less likely to result in dusting exposure of water plant operators than the more powder-like USP-grade sodium fluoride.”

    —–http://www.cdc.gov/fluoridation/fact_sheets/engineering/wfadditives.htm#9

    Paul should once again read the EPA’s rejection of Hirzy’s argument, based on faulty data, that pharmaceutical grade causes less cancer than HFA. I will gladly provide him a copy of this rejection if he has misplaced his.

    As Paul well knows, there is no need for “better control of dose” of fluoride. Water is fluoridated at 0.7 mg/liter. Based on the estimation of the CDC that 75% of daily fluoride intake is from water and other beverages, it is an easy calculation to determine daily “dose” of fluoride intake from all sources. Based on the Institute of Medicine’s established upper limit of daily fluoride intake before adverse effect, is easy to see that before this upper limit will be approached, water toxicity will be the problem, not fluoride. Paul needs to cease with this red herring “dose” nonsense. It has no merit.

    Ss far as his dependence on the 27 Chinese studies, the invalidity of these studies has been well established, yet he continues to attempt to use them as “support” for his flawed ideology.

    Lastly, “fluoridealert.org” is not a valid reference for anything. If he wants to cite valid support for his opinions, then he needs to cite primary sources and not attempt to steer readers to the filtered and edited “information” on his own website. This is akin to his stating his claims are valid because he says so.

    Steven D. Slott, DDS

  5. Yes, Steve. I have corrected him twice on this and he continues to misrepresent the situation. Seems that the anti-fluoride people have a lot investe3d in that misrepresentation. They certainly push this bait and switch fallacy very hard in NZ.

  6. What is complete ignorance? Can you fill us in who are new to the topic Matt?

    Wha…? Huh? Wh…

    Poor Janet. She’s so helpless.

  7. ChristopherAtkinson

    Fascinating that (Dr) Connet relies so heavily on the Choi study and treats the results as a fact that somehow this study proves fluoridated water reduces IQ levels.

    Anyone who believes this read this study. Please.
    This study does not say this.

    Then read the critique…NZ Medical Council.; Journal of the New Zealand Medical Association, 31-May-2013, Vol 126 No 1375.

    It is absurd and embarrassing that a person would rely on this in a scientific context.

    But…I suppose I am naïve to pretend that the issue here is scientific…

  8. Yes, Christopher, whatever gave you the screwy idea that this is about science?

    If Connett would focus more on the valid science, understand that there is an enormous wealth of available, accurate information outside of his infamous 27, and quit pushing sales of his book that no one will waste their time critiquing for him, then he might actually contribute something of value to this online debate.

    Steven D. Slott, DDS

  9. Buy my book.
    Hmm, no.
    I’ll stick to the science.

    6. Evolution vs. Creationism:Experts vs. Scientists-Peer Review

  10. It isn’t about science. The last time I checked, dentistry wasn’t a science (no disrespect intended)

    Science can tell us things about the world around us, but what we put in our bodies is a matter of personal choice and public policy. Science can give us a platform upon which to make those decisions, but it is not the final arbiter in those decisions.

  11. Janet, you just keep getting funnier and funnier. No disrespect taken. Your statement is a reflection of your ignorance of healthcare, not of any disrespect to the art and science of dentistry.

    Steven D. Slott, DDS

  12. gosh United States Pharmacopeia (USP) Grade Fluoride Products…cant believe you are saying these are less pure than whats being used to Fluoridate our water supplies…this the stuff dentists use in our mouths isn’t it ???
    Suggest that Paul would expect, like I would, it would be at least 99% pure..my bag…see typical analysis
    SODIUM FLUORIDE AR
    Cas No 7681-49-4
    Molecular Formula NaF
    Molecular Weight 41.99
    Description White solid.
    Assay min.99%
    Insoluble matter max.0.005%
    Chloride (Cl) max.0.002%
    Titrable acid max.0.04 %
    Titrable base max.0.01 %
    Sodium fluosilicate(Na2SiF6 max.0.12%
    Sulphate (SO4) max.0.005%
    Iron (Fe) max.0.002%
    Heavy Metals (Pb) max.0.002%
    Potassium(K) max.0.01 %
    http://www.dnsexportsindia.com/sodium-fluoride.html

    Sodium silicofluoride (SSF), a powder, is used at our Te Marua, Wainuiomata and Waterloo treatment plants. The SSF we use has a minimum purity of 98.5% and is regularly tested to ensure that the minute quantities of other chemical elements, such as metals, that it contains are well within the maximum safe limits described in the Drinking Water Standards for New Zealand.
    http://www.dnsexportsindia.com/sodium-fluoride.html

    From what I see here we would have at least 0.62% purer product (add back Sodium fluosilicate(Na2SiF6 max.0.12%)

  13. Steve, you seem to find me funny. I am glad I can entertain a dentist.
    Now what parts of the scientific method do you employ when you go to extract a molar for example?

  14. Janet, do you not understand the scientific research that goes into determining the correct method of extracting that molar? Do you not understand that anatomy is science? Do you not understand that histology is science? Do you not understand that pharmacology is science? Do you not understand that pathology is science? Do you not understand that chemistry is science? Do you not understand that physics is science? Do you not understand the research that goes into determining proper diagnoses of dental and systemic disease? Do you not understand the research that goes into understanding such things as the mechanism of fluoride not only on the oral structures but also the rest of the body to which the head is attached???

    Do you not understand the research that goes into understanding the full range of medications that dentists are permitted to prescribe and for which they must fully understand the full effects on the entire body?

    Do you not understand the research that goes into development of the enormous range of materials that dentists use? Do you not understand the research that goes into development of the enormous amount of armamentarium, instrumentation, and technical equipment used by dentists?

    Do you not understand the research that goes into understanding the pathogens with with which dentists must deal and protect against?

    Dentistry not science? Seriously?

    Steven D. Slott, DDS

  15. Gosh, I seem to have struck a nerve. Sorry

  16. No apology necessary, Janet. I’m fully enjoying your comments. Your ignorance of this issue in particular, and healthcare in general, becomes more and more obvious with each comment you make.

  17. That’s good Steve.
    I am going to bake a cake now.
    I will travel to the shop in my vehicle that uses several sciences to provide the manufacture and fuel. I will chose some ingredients that used the very best agricultural science. I will then turn on the oven, that will use electricity that scientists invented, using fuel and technologies that were not around 150 years ago.
    I will watch some daytime TV while the cake is baking, using an LED TV that has transistors and integrated circuits, utilising quantum physics in their design.

    And I do all this, living in ignorant bliss, unaware of the technical marvels that science has given us

  18. Yes, Janet. I fully concur with your last sentence.

    Steven D. Slott, DDS

  19. ChristopherAtkinson

    Scientists invented electrickery?…well I never!

  20. Ian

    The following is the EPA’s response to William Hirzy when he petitioned them to cease using HFA in favor of “pharmaceutical grade” fluoride. Note in particular the conclusion by the EPA that Hirzy’s data actually demonstrated that the cost/benefit favors HFA over pharmaceutical grade NaF, rather than vice versa as Hirzy had erroneously claimed.

    “1. Arsenic. EPA evaluated the cost-benefit analysis submitted by the petitioners and determined that the petitioners miscalculated net benefits for pharmaceutical grade NaF compared to HFSA. Specifically, it appears that the petitioners failed to convert their estimates of lifetime cancer risk to estimates of annual cancer risk for the purpose of calculating annual net benefits. This error alone results in a 70-fold overestimation of the number of annual cancer cases due to arsenic. That is, for the analysis in which the petitioners evaluate arsenic concentrations of 0.078 parts per billion (ppb) due to HFSA and 0.00084 ppb due to pharmaceutical grade NaF, the estimated numbers of cancer cases, when corrected, decrease from 320 to 4.6 per year for HFSA and from 3.4 to 0.05 per year for pharmaceutical grade NaF (Refs. 2 and 9). Similarly, for the analysis in which the petitioners evaluate an arsenic concentration of 0.43 ppb due to HFSA and 0.00084 due to pharmaceutical grade NaF, the estimated numbers of cancer cases, when corrected, decrease from 1,800 to 25 per year for HFSA and from 3.4 to 0.05 per year for pharmaceutical grade NaF (Refs. 2 and 9). After making the correction (i.e., annualizing the lifetime cancer risk), and retaining all other assumptions of the petitioners analysis, the analysis actually indicates that the cost-benefit ratio is in favor of using HFSA over pharmaceutical grade NaF (−$81M/year to −$8M/year, respectively) rather than pharmaceutical grade NaF over HFSA (Ref. 9). As a result, the information submitted by petitioners does not support the petitioners’ claim that there are net benefits in switching from HFSA to pharmaceutical grade NaF. Given that the petition is based upon the premise that the benefits of using pharmaceutical grade NaF as a fluoridation agent significantly exceed the costs relative to the use of HFSA as a fluoridation agent, EPA concludes that petitioners have not set forth sufficient facts to establish that HFSA presents or will present an unreasonable risk of injury to health or the environment with respect to arsenic or that it is necessary to initiate a TSCA section 6(a) rulemaking to protect adequately against such risk. ”

    —-http://www.environmentguru.com/pages/elements/transporter.aspx?id=1297832

    Steven D. Slott, DDS

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