Thursday, March 10, 2011

Fluoridating water, or a funny thing happened on my way to backseat driving

I originally labelled this blog Backseat Driving back in 2004 because I anticipated it to be a blog where I would second-guess decisions made by politicians and other people. That worked out fine more or less until November 2010, when for some reason I was elected to the Santa Clara Valley Water District Board. Turns out that San Jose is the largest city in the US without fluoridated water supplies (in much of the city, anyway), and the seven of us directors have to decide whether we'll help or hinder the fluoridation process. So I'm pushed into the front seat for this one.

We've got some legal and economic issues to handle (it's not quite as cheap as everyone says, I want to know where the money's going to come from), but the relevant issue here is science. I read the guest post at climate blogger Coby Beck's place, The Case Against Fluoride, fairly closely a while back, especially the raucous debate in the comments. As a spectator with some, limited reading of the available information, I'd say the fluoridators seemed more persuasive than skeptics, but it wasn't the absolute demolishing that I expected.

The fluoride skeptics really hurt their cause when say fluoride doesn't prevent cavities - it's so obviously effective that people making this claim are damaging their own credibility. I'd consider it comparable to denying that the planet has warmed in the last 50 years.

The closer issue is adverse effects, and whether a substantial number of people are very slightly harmed by fluoridation, or if a small number of people are substantially harmed. The 2006 National of Sciences report doesn't condemn fluoridation, but it doesn't absolve it, either:
Bone Fractures

....Overall, there was consensus among the committee that there is scientific evidence that under certain conditions fluoride can weaken bone and increase the risk of fractures. The majority of the committee concluded that lifetime exposure to fluoride at drinking-water concentrations of 4 mg/L or higher is likely to increase fracture rates in the population, compared with exposure to 1 mg/L, particularly in some demographic subgroups that are prone to accumulate fluoride into their bones (e.g., people with renal disease)....There were few studies to assess fracture risk in populations exposed to fluoride at 2 mg/L in drinking water. The best available study, from Finland, suggested an increased rate of hip fracture in populations exposed to fluoride at concentrations above 1.5 mg/L. However, this study alone is not sufficient to judge fracture risk for people exposed to fluoride at 2 mg/L. Thus, no conclusions could be drawn about fracture risk or safety at 2 mg/L....


(In California, 2 mg/L was the limit, and 0.7 is the new proposed goal. -Ed)

Neurotoxicity and Neurobehavioral Effects

Animal and human studies of fluoride have been published reporting adverse cognitive and behavioral effects. A few epidemiologic studies of Chinese populations have reported IQ deficits in children exposed to fluoride at 2.5 to 4 mg/L in drinking water. Although the studies lacked sufficient detail for the committee to fully assess their quality and relevance to U.S. populations, the consistency of the results appears significant enough to warrant additional research on the effects of fluoride on intelligence....


Endocrine Effects

The chief endocrine effects of fluoride exposures in experimental animals and in humans include decreased thyroid function, increased calcitonin activity, increased parathyroid hormone activity, secondary hyperparathyroidism, impaired glucose tolerance, and possible effects on timing of sexual maturity. Some of these effects are associated with fluoride intake that is achievable at fluoride concentrations in drinking water of 4 mg/L or less, especially for young children or for individuals with high water intake. Many of the effects could be considered subclinical effects, meaning that they are not adverse health effects. However, recent work on borderline hormonal imbalances and endocrine-disrupting chemicals indicated that adverse health effects, or increased risks for developing adverse effects, might be associated with seemingly mild imbalances or perturbations in hormone concentrations. Further research is needed to explore these possibilities....


Genotoxicity and Carcinogenicity

....Whether fluoride might be associated with bone cancer has been a subject of debate. Bone is the most plausible site for cancer associated with fluoride because of its deposition into bone and its mitogenic effects on bone cells in culture....Several epidemiologic investigations of the relation between fluoride and cancer have been performed since the 1993 evaluation, including both individual-based and ecologic studies. Several studies had significant methodological limitations that made it difficult to draw conclusions. Overall, the results are mixed, with some studies reporting a positive association and others no association.

On the basis of the committee’s collective consideration of data from humans, genotoxicity assays, and studies of mechanisms of action in cell systems (e.g., bone cells in vitro), the evidence on the potential of fluoride to initiate or promote cancers, particularly of the bone, is tentative and mixed. Assessing whether fluoride constitutes a risk factor for osteosarcoma is complicated by the rarity of the disease and the difficulty of characterizing biologic dose because of the ubiquity of population exposure to fluoride and the difficulty of acquiring bone samples in nonaffected individuals.


These were the most troubling findings, mostly about what hasn't been proven, and mostly dealing with levels that are five times what's planned for drinking water. The report expressly ignored the benefits of fluoridation. It's important to balance out potential concerns over rare, severe complications related to fluoride with the certainty that rare, severe complications can result from cavities.


The bottom line as a policy maker in my little arena is that I shouldn't try and figure out the science myself, but I should try to figure out what the scientific consensus is, figure out where the consensus doesn't yet exist, and then plug that information into everything else we have to balance.


The science seems to favor fluoridation, but it's not a slam dunk. And we still have potential policy barriers, and the overall cost issues. Figuring this all out will be interesting.


UPDATE: I'll give the anti-fluoridators credit for quickly finding their way here. Personally, I'm not going to attempt to judge the quality of their sources. I don't care what any single paper or PhD says, I want to know what the consensus says.

13 comments:

  1. Anonymous2:12 AM

    What is important is that others are prepared to make a decisions with out my consent.

    ReplyDelete
  2. HHS: All Infant Formulas Contain Fluoride; Avoid Mixing with Fluoridated Water

    All infant formulas, either concentrated or ready-to-feed, already contain some fluoride and, when routinely mixed with fluoridated water, increase the risk of dental fluorosis (discolored teeth), according to Dr. Howard Koh, Assistant Secretary for Health, US Department of Health and Human Services (HHS) in a video commentary published on Medscape.com, March 8, 2011. (1)

    Fluoride is also in food, beverages, dental products, medicines, and anesthesia and inhaled from ocean mist and air pollution. As a result, more than 41% of adolescents are fluoride-overdosed and afflicted with dental fluorosis - over 3% of it is moderate to severe (brown stains and pitting), according to the Centers for Disease Control. (2)

    The Environmental Protection Agency says, “Exposure to excessive consumption of fluoride over a lifetime may lead to increased likelihood of bone fractures in adults, and may result in effects on bone leading to pain and tenderness.” (3)

    However, no one is studying US children with dental fluorosis to learn whether they also have fluoride-damaged bones or any other fluoride-induced health problems
    Absence of evidence shouldn’t be misinterpreted as absence of harm.

    According to a Journal of the American Dental Association study, "Most infants from birth to age 12 months who consume predominantly powdered and liquid concentrate formula are likely to exceed the upper tolerable limit [of fluoride] if the formula is reconstituted with optimally fluoridated water (0.7 - 1.2 ppm).” (October 2009)

    HHS recently lowered recommended water fluoride levels to 0.7 ppm.

    Clearly, this level is still unsafe for babies. Through water fluoridation, government officials irresponsibly prescribe uncontrolled fluoride doses into children’s bodies without monitoring for harmful health effects.

    Koh says, “…tooth enamel formation occurs from birth until about 8 years old. This is also the time when dental fluorosis may occur with excess fluoride consumption.”

    Koh advises low-fluoride bottled water be used for routinely reconstituting infant formula.

    Fluoride, neither a nutrient nor essential for healthy teeth, was never FDA safety-tested for human ingestion having been "grandfathered in" before the 1938 drug testing laws were enacted. FDA regulates fluoridated toothpaste as a drug for topical application which requires poison warning labeling.

    Twenty-four studies link fluoride to lower IQ in children and 100 animal studies link fluoride to brain damage. (4)

    According to a study in The Anatolian Journal of Cardiology ”Fluorosis has some hormonal, gastrointestinal, hematological, skeletal, renal, respiratory, cardiovascular, immunological, neurological and development side effects.” (5)

    Have we looked for these effects in children who exhibit dental fluorosis? If not, why not?


    References:

    1) Government Perspectives on Healthcare

    HHS: Proposed Guidelines on Fluoride in Drinking Water

    A Commentary By Howard K. Koh, MD, MPH

    http://www.medscape.com/viewarticle/738322



    2) http://www.cdc.gov/nchs/data/databriefs/db53.htm





    3) http://water.epa.gov/drink/contaminants/basicinformation/fluoride.cfm#three



    4) http://fluoridealert.org/iq.studies.html



    5) http://www.anakarder.com/eng/yazilar.asp?yaziid=1877&sayiid=32



    Fluoride levels of infant formulas: http://jada.ada.org/cgi/content-nw/full/140/10/1228/T1

    ReplyDelete
  3. BABY BOTTLE TOOTH DECAY (renamed) EARLY CHILDHOOD CARIES:

    Auge, K. Denver Post Medical Writer. Doctors donate services to restore little girl's smile. The Denver Post, April 13, 2004. (Note: Denver, CO has been fluoridated since 1954.)
    “Sippy cups are the worst invention in history. The problem is parents' propensity to let toddlers bed down with the cups, filled with juice or milk. The result is a sort of sleep-over party for mouth bacteria,” said pediatric dentist Dr. Barbara Hymer as she applied $5,000 worth of silver caps onto a 6-year-old with decayed upper teeth. Dr. Brad Smith, a Denver pediatric dentist estimates that his practice treats up to 300 cases a year of what dentists call Early Childhood Caries. Last year, Children's Hospital did 2,100 dental surgeries, many of which stemmed from the condition, Smith said, and it is especially pervasive among children in poor families.

    Shiboski CH et al. The Association of Early Childhood Caries and Race/Ethnicity Among California Preschool Children. J Pub Health Dent; Vol 63, No 1, Winter 2003.
    Among 2,520 children, the largest proportion with a history of falling asleep sipping milk/sweet substance was among Latinos/Hispanics (72% among Head Start and 65% among non-HS) and HS Asians (56%). Regarding the 30% and 33% resultant decay
    rates respectively; Our analysis did not appear to be affected by whether or not
    children lived in an area with fluoridated water.

    Barnes GP et al. Ethnicity, Location, Age, and Fluoridation Factors in Baby Bottle Tooth Decay and Caries Prevalence of Head Start Children.  Public Health Reports; 107: 167-73, 1992.
    By either of the two criterion i.e., two of the four maxillary incisors or three of the four maxillary incisors, the rate for 5-year-olds was significantly higher than for 3-year-olds.  Children attending centers showed no significant differences based on fluoride status for the total sample or other variables.

    Kelly M et al. The Prevalence of Baby Bottle Tooth Decay Among Two Native American Populations.  J Pub Health Dent; 47:94-97, 1987.
    The prevalence of BBTD in the 18 communities of Head Start children ranged from 17 to 85 percent with a mean of 53%. The surveyed communities had a mixture of fluoridated and non fluoridated drinking water sources.  Regardless of water fluoridation, the prevalence of BBTD remained high at all of the sites surveyed.


    PIT AND FISSURE TOOTH DECAY

    “Fluoride primarily protects the smooth surfaces of teeth, and sealants protect the pits and fissures (grooves), mainly on the chewing surfaces of the back teeth. Although pit and fissure tooth surfaces only comprise about 15% of all permanent tooth surfaces, they were the site of 83% of tooth decay in U.S. children in 1986-87.”
    Selected Findings and Recommendations from the 1993/94 California Oral Health Needs Assessment.

    “Because the surface-specific analysis was used, we learned that almost 90 percent of the remaining decay is found in the pits and fissures (chewing surfaces) of children's teeth; those surfaces that are not as affected by the protective benefit of fluoride.”
    Letter, August 8, 2000, from Jeffrey P. Koplan, M.D., M.P.H., CDC Atlanta GA.

    “Nearly 90 percent of cavities in school children occur in the surfaces of teeth with vulnerable pits and grooves, where fluoride is least effective.”
    Facts From National Institute of Dental Research. Marshall Independent Marshall, MN, 5/92.

    ReplyDelete
  4. Water Fluoridation and the Age-Specific factor

    Both osteosarcoma and hip fracture incidence are significantly linked to water fluoridated at the “optimal” 1 ppm. In three published studies, osteosarcoma is linked to rapidly growing bone of children rather than to adult bone.

    Ph.D. dissertation student Elise Bassin, using the data collected by her Harvard professor Chester Douglass, first eliminated his data for adult males and females and then by looking at exposures for each year of age was able to uncover a 700% increased incidence of osteosarcoma for males exposed to fluoridated water (1 ppm ) between age 5 and 10.

    “The evaluation of age-specific effects distinguishes our study from the other investigations. Rothman (37) has warned that failure to identify the appropriate time window for exposure may result in misclassification which can adversely affect the ability to detect an association.”
    Bassin (2006) Cancer Causes and Control 17: 421-8.

    Likewise, the Journal of American Medical Association, August 12, 1992 hip fracture study showed in Figure 1 that the age specific window-of-injury for women is the approximately fifteen years (perimenopause) prior to menopause, a period of increased bone remodeling and uptake of fluoride. This age specific window resulted in a 100% increase in hip fracture for women at age 75 and would most likely have been much higher had the women grown up on fluoridated water as well.

    Advances in Dental Research 8(1);5-14, June, 1994 “Intake and Metabolism of Fluoride”
    Overall, an average of 86.8% of the dose was retained by the infants, which is about 50% higher than would be expected for adults. They concluded that “…the pharmacokinetics of fluoride in infants reveal(s) a completely different pattern compared to what has been found in adults.” There is a clear need for more information about the renal handling and general metabolism of fluoride in young children and the elderly.”

    ReplyDelete
  5. Here are a few of the citations (http://www.fluoridealert.org/health/teeth/caries/topical-systemic.html) of research that indicate drinking or eating fluoride are NOT helpful in reducing dental decay. Topical fluoride MAY effect dental decay. Many more citations are available through a simple google search.

    "Fluoride is most effective when used topically, after the teeth have erupted."
    SOURCE: Cheng KK, et al. (2007). Adding fluoride to water supplies. British Medical Journal 335(7622):699-702.

    "it is now accepted that systemic fluoride plays a limited role in caries prevention."
    SOURCE: Pizzo G, Piscopo MR, Pizzo I, Giuliana G. (2007). Community water fluoridation and caries prevention: a critical review. Clinical Oral Investigations 11(3):189-93.

    “the major anticaries benefit of fluoride is topical and not systemic.”
    SOURCE: National Research Council. (2006). Fluoride in Drinking Water: A Scientific Review of EPA's Standards. National Academies Press, Washington D.C. p 13.

    "Since the current scientific thought is that the cariostatic activity of fluoride is mainly due to its topical effects, the need to provide systemic fluoride supplementation for caries prevention is questionable."
    SOURCE: European Commission. (2005). The Safety of Fluorine Compounds in Oral Hygiene Products for Children Under the Age of 6 Years. European Commission, Health & Consumer Protection Directorate-General, Scientific Committee on Consumer Products, September 20.

    With a little simple research, it becomes obvious how negative that fluoride is for us. Personally, I ended up in 3rd stage kidney disease before I began doing the research. It was easier to just believe the Fluoride Party Line - which I did until it was almost too late. When I got off fluoridated water and green and black tea (VERY high in fluoride) in 4 months my kidney function was in the normal range again. For real!! I no longer believe Fluoride Party Line. We all need to think for ourselves again.

    My personal story: www.FluorideDetective.com

    ReplyDelete
  6. This comment has been removed by the author.

    ReplyDelete
  7. Another very recent study summarized on http://www.physorg.com/news/2011-03-fluoride-cavities-skin-teeth.html:
    "In a study that the authors describe as lending credence to the idiom, "by the skin of your teeth," scientists are reporting that the protective shield fluoride forms on teeth is up to 100 times thinner than previously believed. It raises questions about how this renowned cavity-fighter really works and could lead to better ways of protecting teeth from decay, the scientists suggest. Their study appears in ACS's journal Langmuir."

    Fluoride's NOT what they told us in years past.
    www.FluorideDetective.com

    ReplyDelete
  8. Anonymous2:00 PM

    Dentists prescribe flouride in vitamins for infants and young children, shouldn't that be sufficient???

    ReplyDelete
  9. Anonymous2:40 PM

    Even if flouride is good for dental health, I don't see any reason it should be added to the water supply. People who want to use flouride can do it many other ways. It's not like this is an area where people can't buy toothpaste and brush their teeth. Neither of my kids (currently in their 20s) have ever had a cavity despite not drinking flouridated water.

    For those of us, like me, who don't want to ingest it due to possible bone and thyroid health issues, it means paying more for water to have this "service" and having to buy bottled water to actually drink.

    And, no, it is not sufficient that dentists prescribe flouride for infants and young children as the previous poster suggests. First of all, that is a small part of the population. Secondly, it's not like people who want it can't get it. And third, sometimes medical professionals change their opinions on protocols after more research has been done.

    ReplyDelete
  10. I interpreted Anon's comment about fluoride in vitamins being "enough" as meaning "no more" but I think dentists themselves would say it's not enough to put in topical applications.

    I'm mainly concerned about children. If it weren't for them this would be a lot tougher question.

    As for people who don't want it, you can get a reverse osmosis system. I know it costs money, but less than bottled water does.

    ReplyDelete
  11. Anonymous10:37 PM

    BABY BOTTLE TOOTH DECAY (renamed) EARLY CHILDHOOD CARIES:

    Auge, K. Denver Post Medical Writer. Doctors donate services to restore little girl's smile. The Denver Post, April 13, 2004. (Note: Denver, CO has been fluoridated since 1954.)
    “Sippy cups are the worst invention in history. The problem is parents' propensity to let toddlers bed down with the cups, filled with juice or milk. The result is a sort of sleep-over party for mouth bacteria,” said pediatric dentist Dr. Barbara Hymer as she applied $5,000 worth of silver caps onto a 6-year-old with decayed upper teeth. Dr. Brad Smith, a Denver pediatric dentist estimates that his practice treats up to 300 cases a year of what dentists call Early Childhood Caries. Last year, Children's Hospital did 2,100 dental surgeries, many of which stemmed from the condition, Smith said, and it is especially pervasive among children in poor families.

    Shiboski CH et al. The Association of Early Childhood Caries and Race/Ethnicity Among California Preschool Children. J Pub Health Dent; Vol 63, No 1, Winter 2003.
    Among 2,520 children, the largest proportion with a history of falling asleep sipping milk/sweet substance was among Latinos/Hispanics (72% among Head Start and 65% among non-HS) and HS Asians (56%). Regarding the 30% and 33% resultant decay
    rates respectively; Our analysis did not appear to be affected by whether or not
    children lived in an area with fluoridated water.

    Barnes GP et al. Ethnicity, Location, Age, and Fluoridation Factors in Baby Bottle Tooth Decay and Caries Prevalence of Head Start Children.  Public Health Reports; 107: 167-73, 1992.
    By either of the two criterion i.e., two of the four maxillary incisors or three of the four maxillary incisors, the rate for 5-year-olds was significantly higher than for 3-year-olds.  Children attending centers showed no significant differences based on fluoride status for the total sample or other variables.

    Kelly M et al. The Prevalence of Baby Bottle Tooth Decay Among Two Native American Populations.  J Pub Health Dent; 47:94-97, 1987.
    The prevalence of BBTD in the 18 communities of Head Start children ranged from 17 to 85 percent with a mean of 53%. The surveyed communities had a mixture of fluoridated and non fluoridated drinking water sources.  Regardless of water fluoridation, the prevalence of BBTD remained high at all of the sites surveyed.

    ReplyDelete
  12. Anon - so babies sleeping with a bottle is bad, unless it just has water in it. I don't see the relevance.

    ReplyDelete
  13. Maureen Jones12:43 PM

    Baby Bottle Tooth Decay and Early Childhood Caries (Cavities) are the same thing. 26% of Santa Clara County children have Baby Bottle Tooth Decay (Health Truth Survey of 2001) for which the Board Members are told fluoridated water will mitigate.

    Rampant tooth decay (7%) is BBTD with extremely high levels of strep mutan bacteria on children's teeth. Please see the above 4 references showing that fluoridated water is of no help at all. In fact, the Shibosky study above is Dr. Howard Pollick's (UCSF) data for preschool children.

    In December '08, UCSF School of Dentistry received from NIH a record $24.4 million grant specifically "to fight early childhood cavities".

    ReplyDelete

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