Presentation on theme: "The Case Against Water Fluoridation"— Presentation transcript:
1The Case Against Water Fluoridation Paul Connett, PhDProfessor Emeritus of Environmental ChemistrySt. Lawrence University, Canton, NYDirector, Fluoride Action NetworkAuckland, NZ, April 2, 2011
2Outline of talk1. Fluoridation is a poor medical practice 2. Fluoridation is unethical 3. The evidence of any benefit is very weak 4. There is no adequate margin of safety to protect the brain from harm and other KNOWN health effects 5. Why does the NZ MOH continue to push fluoridation? 6. The next steps.
4Fluoridation is a poor medical practice 1. Fluoridation is the only time since 1945 we have used the public water supply to deliver medicine.2. You can control CONCENTRATION (mg/liter) at the water works but you can’t control DOSE (mg/day) that people drink.3. You can’t control who gets the medicine.
5Fluoridation is a poor medical practice 4) There is no individual oversight by a doctor5) No health agency is monitoring for side effects6) Fluoride is NOT a nutrient.7) Fluoride is a known toxic substance that interferes with many fundamental biochemical functions
6Fluoridation is a poor medical practice 8. The chemicals used are not pharmaceutical grade as used in dental productsThey come from the wet scrubbers of the phosphate fertilizer industryA spray of water captures two very toxic gases (HF and SiF4) that have caused a great deal of environmental damage.This hazardous waste cannot be dumped into the sea by international law, BUT if this waste is PURCHASED by someone it becomes a PRODUCT and is no longer covered by US hazardous waste regulations!
7Fluoridation is a poor medical practice 9. The main chemicals used are the silicon fluorides:H2SiF6 (hexa fluoro silicic acid) or its sodium salt Na2SiF6 (sodium hexa fluorosilicate).Neither of these chemicals, either in their pure form, or the contaminated solutions used, have been put through any rigorous toxicological testing.
8Proponents claimThat they are merely adjusting the levels of a naturally occurring element.Just because a substance occurs naturally does not make it safe – arsenic occurs naturally!As far as nature is concerned it has made a determination of how much fluoride the baby needs – and it is VERY, VERY small.The proponent’s adjustment is to give a new born baby up to 250 times the level of fluoride in mothers’ milk (1 ppm = 250 x ppm)
9Fluoridation is a poor medical practice In NZ 0.7 – 1.0 ppm fluoride added to water (average 0.85 ppm) 0.85 ppm is over 200 times the level in mothers’ milk (0.004 ppm) A bottle fed baby gets 20,000% the dose a breast fed baby gets
10Proponents claim That water fluoridation is not medication, But the definition of a medicine is a substance given to people to help prevent or combat a disease.Fluoride is added to water to help combat or prevent tooth decay (a disease).Fluoride is being used as a medicine and water fluoridation is “mass medication.”
11Fluoridation is a poor medical practice The official classification of the The US Food and Drug Administration: Fluoride is “an unapproved drug.”The FDA has never regulated fluoride for ingestion. As a result…Fluoridation has never been subjected to randomized clinical trials (RCT) for effectiveness or safety as required for other drugs.
12The FDA does regulate fluoridated toothpaste in the US
18Fluoridation is not ethical 1. No government has the right to force medication on its people to fight a non-contagious, non-life-threatening disease. 2. It deprives individuals of their right to “informed consent to medication.” 3. With fluoridation a government is doing to EVERYONE what a doctor can do to NO ONE.
20Only EIGHT Countries have more than 50% of the population drinking fluoridated water (Australia, Colombia, Ireland, Israel, Malaysia, New Zealand, Singapore and the United States)
2198% of Western Europe now drinks Non-Fluoridated Water AustriaBelgiumDenmarkFinlandFranceGermanyGreeceIcelandItalyLuxembourgNetherlandsNorthern IrelandNorwayScotlandSwedenSwitzerland
2298% of Western Europe now drinks Non-Fluoridated Water Austria*BelgiumDenmarkFinlandFrance*Germany*GreeceIcelandItalyLuxembourgNetherlandsNorthern IrelandNorwayScotlandSwedenSwitzerland**Some fluoridate their salt
23Most countries don’t fluoridate their water, but according to WHO data their kids’ teeth are as good as those that do
24SOURCE: World Health Organization. (Data online)
26NIDR conducted the largest survey of tooth decay ever conducted in the US (1986-7) The teeth of over 39,000 children in 84 communities were examined.
273.4 DMFS NF 2.8 F DMFS The largest US survey of tooth decay Average difference (for year olds) in DMFS
283.4 DMFS NF 2.8 F DMFS Brunelle and Carlos, 1990 Average difference (for year olds) in DMFS= 0.6 tooth surfaces (5 surfaces to a tooth)
29Studies in Australia have found even less saving than O.6 DMFS! Spencer et al. (1996) found a saving in two states of ONLY 0.12 – 0.3 permanent tooth surfaces.Armfield and Spencer (2004) found no statistically significant difference in tooth decay in the permanent teeth between children in South Australia who had drunk fluoridated water all their lives and those who had drunk bottled or tank water.
30“The magnitude of [fluoridation’s] effect is not large in absolute terms, is often not statistically significant,and may not be of clinical significance.”SOURCE: David Locker for the OntarioMinistry of Health & Long Term Care, 1999
31Studies in NZDr. John Colquhoun (1984, 1985, 1987) found no difference in tooth decay between fluoridated and non-fluoridated communities in NZ
33Studies in NZDe Liefde, 1998 described the difference in tooth decay in the permanent teeth as “clinically meaningless”
34Studies in NZ (MOH)Recent studies reported in MOH (2010), “Our Oral Health”“… found that 9-10 year olds continuously exposed to water fluoridation had half the dental caries experience…”The MOH cites four recent NZ studies
35Lee and Dennison, 2004Wellington versus Canterbury saving of 1 DMFS (2.4 – 1.4), MOH, 2010, p.28.1/2.4 x 100 = 41% savingIf Lee and Dennison had comparednon-fluoridated Canterbury (1.28 DMFT) with fluoridated Waikato (1.68 DMFT) and fluoridated Otago (1.42 DMFT). NF Canterbury is 31% and 11% better than F Waikato and F Otago respectively (MOH, 2009 data).
36Kanagaratnam et al., 2009“no signiﬁcant relationship was found between residential ﬂuoridation history and dental caries in the permanent dentition..”
37Schluter et al 2008 Prevalence of caries: Deciduous teeth, prevalence: F = 54.9%, NF = 62.0 % (p=0.05) Saving = 7.1%Permanent teeth prevalence F = 15.9%, NF = 11.7% (p=0.14) Permanent teeth worse in F-areas but not statistically significant
38Mackay and Thomson, 2005 Residence in F area up to age 9 Permanent teeth: DMFSNoneIntermittent 1.18Continuous 0.70Saving = 1.22 – 0.70 = 0.52 DMFS% saving = 0.70/1.22 x 100 = 43%
39Savings in the four studies cited by MOH 0, 0, 0.53 and 1 permanent tooth surfaces out of about 100 permanent tooth surfaces in a child’s mouth
40Percentage savings versus absolute savings Proponents frequently report their findings as percentage savings. This can be very deceptive.We saw in the Mackay and Thomson, 2005 study that a saving of one half of a permanent tooth surface (note there are 4 or 5 surfaces to a tooth) equates to a percentage saving of 43%.The latter sounds more impressive to the general public.
41Delayed eruption in F areas There is some evidence that fluoride delays the eruption of the permanent teeth (Komarek, 2005)A delay of one year would eliminate all the benefits seen in recent studies in NZ.According to the York Review (McDonagh et al. 2000) “No study used an analysis that would control for the frequency of sugar consumption or the number of erupted teeth per child” (York, p.24)
42Delayed eruption of teeth William Kiel, Alamo Heights. Recent Trends in Dental Caries in U.S. Children and the Effect of Water Fluoridationby J.A. Brunelle and J.P. CarlosJournal of Dental Research February 1990 (Volume 69, Special Issue, Pages )Original Data – Age BasedShifted Data – Post-Eruption Based*Adjusted for one yearDelayed eruption of teethWilliam Kiel,Alamo Heights.Mean DMFSMean DMFS*Fluoridated data was shifted back by one year; e.g. age 6 Fluoridated aligns with age 5 unfluoridated, etc.
43Delayed eruption in F areas “The DA (dental age) of the AUS and UK populations was found to be different (Fig. 5). The AUS population had a 0.82 year delay in their DA compared to the UK population. This difference was compared and was found to be very statistically signiﬁcant (P < 0.001).” Peirisi et al. International Journal of Paediatric Dentistry 2009; 19: 367–376
44Important recent studies Komarek et al., 2005 (controlled for delayed eruption of teeth in F-communities).Found no difference in tooth decay between F and non-F communities.Warren et al., 2009 (measured tooth decay as a function of individual exposure to fluoride).Found no relation between tooth decay and amount of fluoride ingested.
45An explanation for weak evidence of benefit in recent studies The major benefits of fluoride are TOPICAL not SYSTEMIC. (CDC, 1999, 2001). In other words fluoride works on the outside surface of the tooth not from inside the body Fluoridation should have ended in 1999!
46It works on the outside of the tooth. Fluoride’s main benefit is TOPICAL.It works on the outside of the tooth.“Its actions primarily are topical for both adults and children."Centers for Disease Control, 1999"Fluoride's predominant effect is posteruptive and topical."Centers for Disease Control, 2001
47NOBEL LAUREATE in MEDICINE 2000 “In pharmacology, if the effect is local (topical), it's awkward to use it in any other way than as a local treatment. I mean this is obvious.You have the teeth there, they're available for you, why drink the stuff?”Dr. ARVID CARLSSON,NOBEL LAUREATE in MEDICINE 2000
48Part 4. There is no adequate margin of safety to protect everyone from known harmful effects of fluoride
49US National Research Council Harmful effects have been carefully documented in a 507-page (1100 references) report by theUS National Research Councilpublished in 2006.
51Harmful effects of FLUORIDE include: 1. Dental fluorosis2. Brain damage3. Lowered thyroid function4. Accumulation in the pineal gland5. Bone damage6. Osteosarcoma?7. Some people very sensitive to very low levels
52Dental FluorosisEarly promoters thought that at 1 ppm F they could limit dental fluorosis to 10% of children in its very mild form.
53Very Mild Dental Fluorosis Impacts up to 25% of tooth surfaceVery Mild Dental Fluorosis
54Impacts up to 50% of tooth surface Mild Dental Fluorosis
55Moderate Dental Fluorosis Impacts 100% of tooth surfaceModerate Dental Fluorosis
56Prevalence and Severity of Dental Fluorosis in the United States, 1999-2004 November 2010: CDC update on fluorosis by Beltrán-Aguilar et al.
59Sensitivity to fluoride’s toxicity may have an ethnic component Afro Americans and Hispanic Americans appear to be more sensitive to fluoride’s toxicity. – They have HIGHER dental fluorosis rates than white Americans in same communities.
60Dental Fluorosis in NZNZ dental fluorosis rates = about 30%
61A KEY QUESTIONWhen fluoride is damaging the baby’s growing tooth cells (causing dental fluorosis) what is it doing to its other developing tissues?
62The baby’s developing brain The baby should NOT be exposed to fluoride of up to 250 times the level of fluoride that occurs in mothers milk
63Arvid Carlsson Nobel Prize for Medicine, 2000 “One wonders what …an increase in the exposure to fluoride, such as occurs in bottle-fed infants …may mean for the development of the brain and the other organs…” 1978
64“it is apparent that fluorides have the ability to National Research Council (2006):Fluoride & the Brain“it is apparent that fluorides have the ability tointerfere with the functions of the brain.”
65Fluoride and the BrainMany more studies on the brain have been published since the NRC reviewThe panel reviewed FIVE IQ studies
66Human studiesAs of 2011, there are now 24 published studies (from China, Iran, India and Mexico) indicating that moderate to high fluoride exposure is associated with lowered IQ in children
67Xiang et al. (2003 a,b)Compared children in two villages ( <0.7 ppm versus ppm F in water)Controlled for lead exposure and iodine intake, and other key variables (NOTE: both lead exposure and low iodine also lower IQ).Found a drop of 5-10 IQ points across the whole age rangeThe whole IQ curve shifted for both males and females
70Estimated that IQ in children lowered at Xiang et al. (2003 a,b)Estimated that IQ in children lowered at1.9 ppm fluoride in water (threshold)
71There is no adequate margin of safety If fluoride is associated with lowering IQ of children at 1.9 ppm in a small population study we need to apply a safety factor to protect the whole population of childrenNormally we use a safety factor of 10 to do thisIf we assume that the Chinese children were drinking one liter of fluoride per day the dose that lowered IQ was 1.9 mg/dayThat would mean to protect the intelligence of ALL the children in a large population a safe dose would be 0.19 mg/day (1.9 divided by 10)
72Xiang et al. (2010) Xiang et al. elaborated on their 2003 study. Added in more details of methods etc.Added in data showing an association between plasma levels of fluoride and lowered IQ.Accepted for publication by Environmental Health Perspectives the journal of the National Institute of Environmental Health Sciences (NIEHS)NIEHS is an agency of the US Department of Health and Human Services (DHHS).Pre-publication copy of this article published onlineArticle withdrawn because Xiang had published some of the data before (conflicts with EHP policy)
73Xiang et al. (2010) Please note: Xiang et al. (2010) paper was NOT withdrawn because the methodology was considered inadequateThe methodology was PEER REVIEWED and the study considered acceptable for publication in the leading US environmental health journal.
74Ding et al. 2011 (J. Hazardous Materials) “Mean value of ﬂuoride in drinking water was 1.31 ±1.05mg/L (range 0.24–2.84).”“ ConclusionsOverall, our study suggested that low levels of ﬂuoride exposure in drinking water had negative effects on children’s intelligence...The results also conﬁrmed the dose–response relationships between urine ﬂuoride concentrations and IQ scores…”
75Ding et al. 2011Fig 2. The relationship between IQ differences and urine fluoride concentrations.Multiple linear regression model was carried out to confirm the association withurine fluoride exposure and IQ scores (F=9.85, p < )
76Ding et al. 2011“an increase in the urine ﬂuoride concentration of 1 mg/L associated with a decrease of 0.59 IQ scores.”
77Two preposterous notions What parent in their right mind would put their children’s teeth above their brains?What government would support a program aimed at lowering tooth decay - by at most 0.6 of one tooth surface – if it lowered the IQ of the population by even a small amount?
78Other health concerns (see chapters 13-19 in The Case Against Fluoride )
80Osteosarcoma: Science vs Politics The science: In 2001, Dr. Elise Bassin (a dentist) successfully defended her PhD thesis at Harvard.She found (in a matched case-control study) that if young boys were exposed to fluoridated water in their 6th,7th or 8th years, they had a 5-7 fold increase in developing osteosarcoma by the age of 20, compared to non-exposed boys.Now the politicsBetween 2001 and 2005, Bassin’s thesis adviser - Prof. Chester Douglass three times concealed her findings (1. From his peers - a meeting of the BFS in 2002; 2. The NRC panel and 3. His funder - the National Institutes of Health (NIH).
81OsteosarcomaThe Science: Bassin publishes research in the May 2006 issue of the journal Cancer Causes and Control.The politics again. In a letter published in the same issue, Douglass promises a study that he claims will discount Bassin’s findings.This promise of a study is being used by promoters of fluoridation to negate concern over Bassin’s findings.Douglass promised his study for the Summer of 2006 –we are still waiting!
82National Research Council (2006): Fluoride & the Thyroid “several lines of information indicate an effect offluoride exposure on thyroid function.”
83IF fluoride lowers thyroid function It could explain:1) delayed eruption of primary teeth2) lowered IQ in children3) Increase in hypothyroidism among US population, plus the accompanying symptoms – obesity, lethargy, tiredness not relieved by sleep etc
84Fluoride & Pineal Gland In 1997 Jennifer Luke confirmed that fluoride accumulates in the human pineal gland. She found an average of 9,000 ppm on the calcium hydroxy apatite crystals (highest 21,000 ppm) (Luke, 2001).In animals (Mongolian gerbils) fluoride lowers melatonin production and shortens time to puberty (Luke, Ph.D. thesis, 1997).
86Fluoride and Children’s Bone The Newburgh-Kingston, NY trial (Schlesinger et al, 1956) also reported about twice the incidence of cortical bone defects in the children in the fluoridated community (13.5%) compared with the non-fluoridated community (7.5%).
87Alarcon-Herrera et al. (2001) In a Mexican study researchers found that as the severity of dental fluorosis went up so did the incidence of bone fractures in both children and adults
89ArthritisThe first symptoms of fluoride’s poisoning of bone are identical to arthritis (stiffness, aching joints and pain in the bones)According to the CDC, arthritis affects 68 million people in the US - 1 in 3 American adultsNo fluoridated country is collecting fluoride bone levels in a systematic fashion to check a possible connection with arthritis or other bone problems!
90Fluoride & Skeletal System National Research Council (2006):Fluoride & Skeletal System"All members of the committee agreed thatthere is scientific evidence that under certain conditionsfluoride can weaken bone and increase the risk of fractures.”
92Fluoride levels in teaHigh concentrations of fluoride have been reported in the tea drinks of India, Tibet, and China:Gulati et al. 1993:1.55 – 3.21 mg/lCao et al. 1996: – 4.32 mg/lFung et al., 1999: 1.60 – 7.34 mg/l.
93Fluoride levels in tea Gulati et al. 1993:1.55 – 3.21 mg/l Cao et al. 1996: – 4.32 mg/lFung et al., 1999: 1.60 – 7.34 mg/l.I liter = 8 cups or 4 mugs8 cups of tea/day = 0.76 – 7.34 mg/day16 cups of tea/day = mg/dayA heavy tea drinker could damage their bones
94Fluoride levels in teaHigh concentrations of fluoride have been reported in the tea drinks of India, Tibet, and China:Gulati et al. 1993:1.55 – 3.21 mg/lCao et al. 1996: – 4.32 mg/lFung et al., 1999: 1.60 – 7.34 mg/l.
95Fluoride levels in tea Gulati et al. 1993:1.55 – 3.21 mg/l Cao et al. 1996: – 4.32 mg/lFung et al., 1999: 1.60 – 7.34 mg/l.I liter = 8 cups or 4 mugs8 cups of tea/day = 0.76 – 7.34 mg/day16 cups of tea/day = mg/dayA heavy tea drinker could damage their bones
96Key Health Studies have NOT been done in most fluoridating countries NO INVESTIGATION of a possible relationship between consumption of fluoridated water andlowered IQ in children (except one small study in NZ),behavioral changes in children (attention deficit etc)arthritic symptoms in adults,hypo-thyroidism (underactive thyroid),increased bone fractures in children,Melatonin levels in childrenEarlier onset of puberty,Alzheimer’s disease in adults, and
97There has been NO FORMAL INVESTIGATION of the many anecdotal reports and case studies (and one clinical trial) that some individuals are highly sensitive to fluoride (e.g. gastrointestinal, neurological and skin conditions)See Fluoride Fatigue (Spittle, 2008)
98If you don’t look, you don’t find! The absence of studies, does not mean the absence of harmDr. Peter Cooney, the Chief Dental Officer of Canada, told an audience in Dryden, Ontario (April 1, 2008),“I walked down your High Street today, and I didn’t see anyone growing horns, and you have been fluoridated for 40 years!”
99WHY?The only rational explanation for so much irrational (or irresponsible) behavior on the part of health agencies that continue to promote water fluoridation even though the science indicates that it is neither effective nor safe, IN MY OPINION is becauseit has become more important to protect this practice than it is to protect the health of the people they represent…Why should that be?
100Why does the dental lobby continue to promote fluoridation? They are very proud of this practiceFluoridation helped to establish dentistry on a par with medicineFluoridation is the backbone of public health dentistryFluoridation has made careers, reputations and provides money for endless research on teeth
101Why do health bureaucracies continue to promote fluoridation? We have to do look at this at three levels:At the bottomIn the middleAt the top of the bureaucracies (or chain of command)
102At the bottom of the chain of command We have thousands of doctors and dentists who truly BELIEVE that fluoridation works. This was all they were taught at dental and medical school. Now most are so busy treating patients that they don’t have time to read the literature. They take the word of professional bodies and health agencies at face value.
103In the middle of the chain of command Within the chain of command we have bureaucrats who are trained to PROMOTE NOT to QUESTION policy (i.e. their jobs depend upon promoting fluoridation)
104At the top of the chain of command At the top of the chain of command of the health agencies in fluoridating countries the major concern is:Losing credibility
105Why do health agencies like the NZ MOH continue to promote fluoridation? Lose fluoridation = lose credibilityLose credibility = lose (or threaten) the public’s trust in other important public health policiesPublic health policies require the public’s trustMY RESPONSE: I argue that by coming clean and stopping their support for fluoridation (switching to promoting TOPICAL treatments and investing in education for a better diet) health agencies (like NZ MOH) would improve their credibility and regain the public’s trust.
106Heavy tea drinkers are already getting too much fluoride
107MY RESPONSEI argue that by coming clean and stopping their support for fluoridation (switching to promoting TOPICAL treatments and investing in education for a better diet) health agencies (like NZ MOH) would improve their credibility and begin to regain the public’s trust.
108THE SCIENCE INDICATES THAT FLUORIDATION SHOULD BE ENDED SEE FAN-NZ’s website FANNZ.org.nzSEE FAN’s website FluorideALERT.orgSEE FAN’s health data baseSEE the NRC (2006) report ONLINESEE the 28-minute video “Professional Perspectives on Water Fluoridation”SEE our book, “The Case Against Fluoride”
109Book to be publishedby Chelsea GreenOctober, 2010Can be ordered nowon Amazon.comMeanwhile, seeFluorideAlert.orgfor more information
110The Next Step We have done our job as scientists We have outlined our case in detailWe have documented every fact and argument we have presentedNow we need health authorities to do their jobEither respond scientifically to our case oradmit that fluoridation was a HUGE MISTAKE and STOP IT NOW!
111Is like driving a nail through a piece of wood EFFECTING CHANGEIs like driving a nail through a piece of wood
115More evidence that promoters of fluoridation are more interested in protecting this practice than protecting our health
116In Nov, 2006, the American Dental Association told its members "If using a product that needs to be reconstituted,parents and caregivers should consider usingwater that has no or low levels of fluoride." SOURCE: American Dental Association, Nov 9, 2006
117BUT parents are not Being warned! "If using a product that needs to be reconstituted,parents and caregivers should consider usingwater that has no or low levels of fluoride." SOURCE: American Dental Association, Nov 9, 2006
118We need to get this warning to parents This warning should be inserted in water bills: “Parents should not use tap water to make up baby formula”
119The difference between science and politics In science you examine the data and draw a conclusionIn politics you reach a conclusion and then select the data to support that conclusion
120POLITICS versus SCIENCE A good example ofhow promoters’ putpolitics above scienceis the way they treatedthe landmark NRC(2006) report.
121The NRC report NRC published their report on March 22, 2006 The panel concluded that the “safe” drinking water standard for fluoride (the MCL and MCLG of 4 ppm) was not protective of healthThey recommended that the EPA do a health risk assessment to determine a new MCLG
122POLITICS versus SCIENCE On the same day as the NRC published its report the ADA declared the NRC review was irrelevant to water fluoridation! They stated that 4 ppm was much higher than the level used in fluoridation ( ppm)Six days later the CDC declared that NRC report was consistent with their promotion of fluoridation at 1 ppmIn 2007, the Australian NHMRC said NRC report not relevant to AustraliaIn Feb. 2009, the Strategic Health Authority in Southampton, UK, said NRC report not relevant to fluoridation in UK
123POLITICS versus SCIENCE There are FOUR problems with these dismissals of the relevance of the NRC (2006) review:1) They didn’t wait for the EPA to determine a new MCLG, or attempt their own2) They are confusing concentration and dose. Someone consuming a lot of water at 1 ppm could get a higher dose than someone consuming a little water at 4 ppm (or less than 4 ppm when a new MCLG is determined)3) They didn’t attempt a margin of safety analysis on the levels causing harm reported in the NRC report.4) They didn’t note that in chapter 2 the NRC panel showed that subsets of the population were exceeding the EPA IRIS reference dose drinking water at 1 ppm fluoride
124THE US EPAOn Jan 7, 2011 (after 5 years) the EPA has begun a process that will eventually a determine a new “safe” drinking water standard (MCL) or goal (MCLG)If EPA did this job honestly using routine assumptions and methods used in regulatory health risk assessments it would force a new MCLG LESS than 1 ppmAnd end water fluoridation overnight!
125THE US EPAHowever on Jan 7, 2011 EPA spokesperson made it clear that they will be determining a new “safe” MCLG which would not interfere with the “benefits” of the water fluoridation program.In my view that would be impossible to do honestly (note my calculations on IQ lowering)It is also a violation of the Safe Drinking Water Act which it makes it clear that the MCLG should protect all the people from both known and reasonably anticipated health effects– any consideration of “supposed” benefits should not interfere with this determination
127Sensitivity analysis for IQ risk assessment If the Chinese children were drinking 0.5 liter, LOAEL for lowered IQ = 0.95 mg/day. Safe dose to protect whole population = mg/day.If the Chinese children were drinking 2 liters, lowered IQ at 3.8 mg/day. Safe dose to protect whole population = 0.38 mg/day (less than two glasses of water)If we reduced margin of safety to 5 (instead of 10) Safe dose = mg/day (equivalent to ml of water at 1 ppm a day)
128Fluoride & the thyroid gland European doctors (1930’s to 50’s) used sodium fluoride to reduce thyroid activity in patients with hyperthyroidism (over active thyroid gland).The doses used by Galletti and Joyet (1958) mg of fluoride per day - are currently exceeded by some people living in 1 ppm communities
129Bachinskii 1985 2.3 ppm of fluoride in water “was a risk factor of more rapid development of thyroid pathology.”
130Lin et al., 1991Lin et al. found that for mothers with borderline iodine exposure the IQ in their offspring was further lowered by drinking water at 0.9 ppm fluoridei.e. fluoride exposure makes low iodine intake worse
131Fluoride levels in teaHigh concentrations of fluoride have been reported in the tea drinks of India, Tibet, and China:Gulati et al. 1993:1.55 – 3.21 mg/lCao et al. 1996: – 4.32 mg/lFung et al., 1999: 1.60 – 7.34 mg/l.
132Fluoride levels in tea Gulati et al. 1993:1.55 – 3.21 mg/l Cao et al. 1996: – 4.32 mg/lFung et al., 1999: 1.60 – 7.34 mg/l.I liter = 8 cups or 4 mugs8 cups of tea/day = 0.76 – 7.34 mg/day16 cups of tea/day = mg/dayA heavy tea drinker could damage their bones
134Percent 50 USA States and DC National Survey of Children's Health.U.S. Department of Health and Human Services, Health Resources and Services Administration, Maternal and Child Health Bureau.The National Survey of Children's Health Rockville, Maryland: U.S. Department of Health and Human Services, 2005