Harm to susceptible populations of aquatic life and humans due to the addition of fluoride (fluorosilicates) in drinking water

Petition

Petition under the Auditor General Act, section 22 requesting the discontinuation of artificial water fluoridation

The addition of H2SiF6 and NaSiF6 (fluorosilicates) is causing health harm to susceptible populations of aquatic life and humans in violation of the Fishing Act, section 34(1), which describes the provisions to conserve and protect fish habitat that sustain Canada’s fisheries resources; the harmful alteration, section 35(1), which prohibits the harmful alteration, disruption or destruction (HADD) of fish habitat; and sections 36-42 which control the deposition of any deleterious substance to water frequented by fish.

Name:         James S. Beck, M.D., Ph.D.
Address:     4959 Vantage Cres. NW
                    Calgary, Alberta T3A 1X6
Email:          beck@ucalgary.ca
Telephone:  (403)286-4977
Signature:    [Original signed by James S. Beck]

Office of the Auditor General of Canada
Commissioner of the Environment and Sustainable Development
Attention: Petitions
240 Sparks Street
Ottawa, Ontario K1A 0G6

Toll free:          1-888-761-5953 (toll free)
Telephone:       613-995-3708
Fax:                 613-941-8286
Email:              petitions@oag-bvg.gc.ca

Introduction

Water fluoridation, a sixty-year-old policy, generally exposes entire populations to 1 mg F-/L in the drinking water and unknown quantities of fluorosilicates. The work of Marier and Rose of the National Research Council (NRC) of Canada,¹ the more recent research by the United States NRC 2006 committee,² the 1993 Agency for Toxic Substances and Disease Registry (ATSDR)³ from the United States Public Health Service and the 1979 Report prepared for the Minister of the Environment in Quebec⁴ enables one to predict that an adult exposed to water containing 1ppm of fluoride (here “fluoride” is used to indicate F in all forms) will consume on average between 2 and 4 mg of fluoride per day from fluoridated water.

Several government documents^1-4 include discussion of the various susceptible populations who retain greater than normal amounts of F- (kidney patients, young children), ingest more than average amounts of water (10 liters or more—see below) or who have a particular intolerance to chronic exposures of small amounts of F-. These people have been shown to demonstrate adverse health effects such as dental and skeletal fluorosis and disruption of vital endocrine organs (thyroid, parathyroid, pancreas, etc.) resulting in exacerbation or promotion of symptoms of hypothyroidism, kidney failure, diabetes and cardiovascular disease, to name just a few.

According to the WHO 2002 Fluorides: Environmental Health Criteria 227; “adult intakes exceeding 5 mg of fluoride per day from all sources probably pose a significant risk of skeletal fluorosis.”

According to the NRC 2006 (p. 263) Report on Fluorides in Drinking Water, a 70 kg person ingesting 0.7 mg fluoride per day, if iodine-desufficient, may experience suppressed thyroid function; “In humans effects on thyroid function were associated with fluoride exposures of 0.05–0.13 mg/kg/day when iodine intake was adequate and 0.01–0.03 mg/kg/day when iodine intake was inadequate…”. According to the Centers for Disease Control (CDC), the average urinary iodine level today is half what it was in 1971. The agency estimates that 36% of U.S. women now have sub-optimal iodine intake (http://www.cdc.gov/nchs/products/pubs/pubd/hestats/iodine.htm).

Background levels of fluoride for Lake Ontario and the St. Lawrence River are up to 0.25mg/L which is double the 0.12mg/L Canadian Water Quality Guideline (CWQG) [Drinking Water Surveillance Program (DWSP) http://www.ene.gov.on.ca/envision/water/dwsp/0002/eastern/eastern.htm].

Evidence from the study by Daemker and Dey (1989) indicates that some species of fish (salmon) are harmed at levels of about 0.25mg/L.²⁰ Levels below 0.1 ppm were shown to be lethal to the water flea, Daphnia magna.²¹ These two studies suggest that salmon species also may be affected by fluoride-induced reduction of food supply as well as fluoride-induced chemical barriers to migration.

The evidence suggests health harm to susceptible aquatic species, land species and humans. The additions of toxic substances hydrofluorosilicic acid, arsenic, lead, mercury, etc. are therefore not justifiable.

Research evidence
Table 2-4 from the NRC 2006 report shows information regarding water and fluoride ingestion, assuming a fluoride concentration of 0.7-1.2mg/L (blanketing the recommended fluoride concentration of 0.8-1.0mg/L recommended by Health Canada).

Nephrogenic diabetes insipidus patients (70kg):

• typically consume 3.5 liters of water/day;
• typically consume 2.5 – 4.2 mg/day of fluoride from water alone;
• high consumers (reasonably high but not upper bound levels) ingest 10.5 liters of water/day;
• high consumers (reasonably high but not upper bound levels) ingest 7.3-13 mg/day of fluoride from water alone.

These levels of consumption exceed the Health Canada TDI. The Health Canada TDI is reportedly 105 µg/kg body weight/day which would be 7.35mg/day for a 70 kg Canadian adult.

Water/day                                Fluoride consumed/day
1L/day                          0.6        0.8        1.0        1.2        1.5(mg/day)
2L/day                          1.2        1.6        2.0        2.4        3.0
3L/day                          1.8        2.4        3.0        3.6        4.5
4L/day                          2.4        3.2        4.0        4.8        6.0
5L/day                          3.0        4.0        5.0        6.0        7.5
6L/day                          3.6        4.8        6.0        7.2        9.0
7L/day                          4.2        5.6        7.0        8.4        10.5
8L/day                          4.8        6.4        8.0        9.6        12.0
9L/day                          5.4        7.2        9.0        10.8      13.5
10L/day                        6.0        8.0        10.0      12.0      15.0
11L/day                        6.6        8.8        11.0      13.2      16.5

Someone with nephrogenic diabetes insipidus would exceed the TDI from drinking water sources alone. (10.5liters x 0.8mg/L = 8.4mg/day of fluoride) (10.5liters x 1.0mg/L = 10.5mg/day of fluoride) Athletes and workers also exceed the TDI (8.4liters x 0.8mg/L = 6.72mg/day of fluoride) (8.4liters x 1.0mg/L = 8.4mg/day of fluoride).

This calculation does not include the steadily increasing fluoride exposure from other sources. Any discussion of fluorides in drinking water must acknowledge the global increases of sources of fluoride. Fluoride is present in the air, water, foods (pesticides, fertilizers and post-harvest fumigants contribute to the fluoride content in our food), consumer products and drugs. Increased uses of fluoridated drinking water in the processing of foods and beverages has a certain multiplier effect in the food chain, as discussed in the report prepared for the Quebec Minister of the Environment in 1979⁴ and other sources.^1-3,5,7

Health effects

• The daily dose is determined by how much fluoridated water is consumed in a day plus how much fluoride you consume from other sources: dental products, consumer products, air, food.
• The load in various body organs is influenced by how well your body eliminates fluoride.
• The dose is influenced by the nutritional status of an individual.The amount in the body is cumulative over a lifetime.
• Dosage is related to body weight (babies consume more water per unit weight).

We cannot control the dose of fluoride because we cannot tell individuals how much to drink; we have no idea how much fluoride exposure individuals receive from air, dental products, consumer products, drugs, foods and beverages using artificially fluoridated water, pesticides and fertilizers. Due to this inability to control the dose, it is reasonable to assume that the incidence and severity of adverse health effects is likely to rise with the increases in fluoride exposures from all sources. Fluoride in drinking water is the easiest source of fluoride to eliminate to minimize exposure.

Not only are municipalities unable to control the dose (the amount of fluoride consumed in a day), but the concentration of fluoride in our drinking water may be poorly controlled. The Region of Waterloo 2005 Annual Reports show that the recommended guidelines for fluoride concentration were achieved between 7.2-74.7% of the time. The Region of Waterloo 2006 Annual Report showed that fluoride concentration levels in water exceeded the recommended guidelines several times (e.g. 3.3mg/L May 22-24, 2006). These results roughly correspond with the work by Reeves8 who reported that only 65% of fluoridated water systems meet their target levels of fluoride in the drinking water.

Susceptible populations (Canadian NRC 1977, ATSDR 1993, US NRC 2006)

• 1-5% of population are hypersensitive to fluoride.
• 5% of population are diabetic.
• 5% of population have renal disease.
• 5 % of population have cardiovascular disease.
• 5% of population have thyroid dysfunction.
• 27-44% of diets are low in calcium, magnesium, iodine (EPA/CDC).

Young children

• eliminate only 15% of ingested fluoride (Whitford 1994);
• consume more water per body weight than adults.
• Young males up to age 20 who use fluoridated water are 5-7 times more susceptible to bone cancer than are those who use non-fluoridated water.⁸

People who are unable to filter toxins adequately include those with

• kidney disease where less fluoride is eliminated,
• disorders of water and sodium metabolism such as diabetes insipidus.

People who consume more water than average include

• those with high activity levels (e.g., athletes, workers with physically demanding duties, military personnel),
• people living in hot climates, especially outdoor workers,
• pregnant and lactating women,
• people with health conditions that affect water intake such as diabetes mellitus and conditions requiring rapid rehydration such as gastrointestinal upsets or food poisoning (EPA 2000a).

York Review 2000

Two authors of the 2000 “York Review” from Britain and three authors of the recent NRC 2006 Review recently signed a petition asking for the discontinuation of water fluoridation.

Two advisors of the 2000 York Review recently stated: “Water fluoridation has not been proved to reduce tooth decay” and “No drug would be licensed for effectiveness or safety on the present evidence” and “if fluoride is a medicine, evidence on its effects should be subject to the standards of proof expected of drugs, including evidence from randomised trials…. There have been no randomised trials of water fluoridation.” (Cheng KK, Chalmer I, Sheldon TA 2007 British Medical Journal October 6, 335: 699-702).

Ontario Ministry of Health & Long-term Care, 1999 Review

“The magnitude of [fluoridation’s] effect is not large in absolute terms, is often not statistically significant, and may not be of clinical significance… Canadian studies do not provide systematic evidence that water fluoridation is effective in reducing decay in contemporary child populations. The few studies of communities where fluoridation has been withdrawn do not suggest significant increases in dental caries as a result.”

“Current studies support the view that dental fluorosis has increased in both fluoridated and non-fluoridated communities. North American studies suggest rates of 20 to 75% in the former and 12 to 45% in the latter.”

“In Canada, actual intakes are larger than recommended intakes for formula-fed infants and those living in fluoridated communities. Efforts are required to reduce intakes among the most vulnerable age group, children aged 7 months to 4 years.”

“In the absence of comprehensive, high-quality evidence with respect to the benefits and risks of water fluoridation, the moral status of advocacy for this practice is, at best, indeterminate, and could perhaps be considered immoral.” Cohen H, Locker D. The Science and Ethics of Water Fluoridation, Journal of the Canadian Dental Association. 2001 67(10): 578-80.

The 2007 Pizzo et al. review:
“It is now accepted that systemic fluoride plays a limited role in caries prevention.” Giuseppe Pizzo, Maria Piscopo, Ignazio Pizzo and Giovanna Giulliana. Community water fluoridation and caries prevention: a critical review. Clinical and Oral Investigations Sept 2007;11(3):189-193.

Aluminum-fluoride (AlFx) – synergistic effects
Fluoride and AlFx are demonstrated to inhibit antioxidant enzymes, induce free-radical generation, induce lipid peroxidation in the brain, activate inflammatory ecosanoid pathways, depress mitochondrial energy production, depress melatonin.¹⁶

The potential for impairing homeostasis, development, behaviour and cognition is significant. The use of calcium, vitamins C,D,E and iodine have all been reported to ameliorate these effects.¹⁶ Fluoride has been known to influence the activity of many enzymes for some time. It has now been demonstrated that many of these effects are due to the synergistic action of fluoride in combination with aluminum (AlFx). Fluoride, AlFx and aluminum are all known to interfere with enzymes necessary for cellular energy production.¹⁶

Phosphoryl transfer is the fundamental mechanism underlying energy metabolism and signal transduction in cells. AlFx is an inorganic molecule that mimics the chemical structure of a phosphate. As phosphate analogs, they affect the activity of phosphoryl transfer enzymes, such as GTPases, ATPases, phosphohydrolyases, phospholipase D.¹⁷

Fluoride is also known as the “universal G protein activator” in biochemistry, meaning it can activate all G protein families.¹⁸ As such, AlFx sends false messages which are then amplified with the involvement of the various G proteins. G proteins are cell transducers which relay and amplify signals from outside of cells to the inside of cells. According to the NRC 2006 Report,² “Aluminum combined with fluoride in very small quantities [0.5mg/L] influences the following: Thyroid Hormone; Growth Hormone; Melatonin; Neural Transmitters; Insulin/Glucagon; Prostaglandins; Vasopressin etc.”

QUESTIONS

1. What is clearly emerging in the research literature is that fluoride is a toxic substance which should not be ingested. What does Health Canada consider to be a safe daily dosage of fluoride, with an adequate safety margin? Please consider all potential recipients including persons with thyroid disease, presons with kidney disease, infants and children and fetuses. Please show calculations, justifications and references for your determination.
2. How can a Canadian citizen determine the daily dose of fluoride from all sources? Please show calculations and references to justify your response.
3. Health Canada warns against all intake sources of fluorides from toothpaste, mouthwash, and supplements for young children under 6. Health Canada also warns the public not to give fluoridated dental products to children: “Children under six years of age should be supervised while brushing, and children under the age of three should have their teeth brushed by an adult without using any toothpaste.” “Never give fluoridated mouthwash or mouth rinses to children under six years of age, as they may swallow it.” Health Canada's "Fluoride-Containing Anti-Caries Products Monograph" states that the labels of fluoride containing mouthwashes and toothpastes must carry the following cautionary statement by 2009: "If more than used for brushing is accidentally swallowed, get medical help or contact a Poison Control Centre right away". Why is the pharmaceutical grade fluoride from toothpaste considered to be unsafe and yet the industrial grade fluoride from water is considered to be safe? Please provide references.
4. “The major dietary source of fluoride for most people in the United States is fluoridated water…” (NRC 2006 p.24) Why does Health Canada not advise against this fluoride source intake for young children?
5. Does Health Canada believe that one can control the daily dose of fluoride ingested from fluoride in food and beverages? If so, how? If not, how do you justify ignoring such sources? Please show calculations and references to justify your response.
6. According to Health Canada, prescribing controlled doses of pharmaceutical grade of fluoride, under the care of a doctor is no longer recommended. "Health Canada does not recommend the use of fluoride supplements (drops or tablets). This guideline is consistent with recommendations made by Health Canada's First Nations and Inuit Health Branch (FNIHB) and the Canadian Association of Public Health Dentistry (CAPHD)." (http://www.hc-sc.gc.ca/iyh-vsv/environ/fluor_e.html) Why is the use of uncontrolled doses of hydrofluorosilicic acid, an industrial grade of fluoride which is not regulated by our federal government (it has no DIN) promoted for use in our drinking water in Canada by the Public Health Service and Health Canada when controlled doses of pharmaceutical grade fluorides are not recommended? Does Health Canada believe that administering uncontrolled doses is preferable to controlled doses?
7. Examples of high water consumers from NRC 2006 illustrate that many individuals consume more than 5mg/day, while the WHO states that bone effects are expected to occur with such exposure. Does Health Canada consider these individuals to be consuming a safe dose?
8. The 2006 Fluoride in Drinking Water: A Scientific Review of EPA’s Standards does a risk assessment which illustrates that many individuals consume more than 0.7mg/day where many (especially women) may be vulnerable to thyroid effects. Does Health Canada disagree with the risk assessment done by the NRC 2006 Committee? If so, on what points and why? If you agree, why does Health Canada insist that recommended concentration levels are safe for everyone? Please provide references you use to come to your conclusions.

REFERENCES

1. Rose D, Marier JR. Environmental Fluoride 1977 Associate Committee on Scientific Criteria for Environmental Quality. National Research Council, Canada, 1977.
2. NRC (National Research Council). 2006. Fluoride in Drinking Water: A Scientific Review of EPA’s Standards. Washington, DC: The National Academies Press. [Available at http://www.nap.edu/catalog/11571.html]
3. A Toxicological Profile by the U.S. Dept. of Health and Human Services, Public Health Service, Agency for Toxic Substances and Disease Registry (ATSDR) TP – 91/17, Pages 3-4, Section 1.2, Paragraph 7 (Public Health Statement), April 1993.
4. Report prepared for the Minister of the Environment by the Advisory Committee on the fluoridation of Water Supplies. Fluorides, Fluoridation and Environmental Quality. November 1979.
5. Morin JP, Remington Graham J, Parent G. La fluoration: Autopsie d’une erreur scientifique. Berger. 2005, chapitre 7.
6. World Health Organization Geneva, 2002 Environmental Health Criteria 227. http://www.intox.org/databank/documents/chemical/fluoride/ehc227.htm
7. Martin DJ. Fluoride Content of vegetables cooked in fluoride containing water. J Dent Res 30:676.
8.  Bassin EB, Wypij D, Davis RB, Mittleman MA. (2006). Age-specific fluoride exposure in drinking water and osteosarcoma (United States). Cancer Causes and Control 17: 421-8
9. Reeves TG (1996) Status and strategic plans for fluoridation: Centers for Disease Control. J Public Health Dent 56:242–245.
10. Smith G.E., Fluoride and bone : an unusual hypothesis. Xenobiotica. 1985 15(3):177-186.
11. Gray AS. Time for a new base line? 1987 J. Canadian Dent Assoc 10:763-765.
12. "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... There is a clear need for more information about the renal handling and general metabolism of fluoride in young children..." Whitford GM. (1994). Intake and metabolism of fluoride. Advances in Dental Research 8:5-14.
13. Cox, W.R. 1953. Hello test Animals... Chinchillas or You and Children. Olsen Publ. Co., Milwaukee. Wis.
14. Justus CJ, Krook LP. (2006). Allergy in horses from artificially fluoridated water. Fluoride 39:89-94.
15. Krook LP, Justus C. 2006 Fluoride poisoning of horses from artificially fluoridated drinking water. Fluoride 39(1)3–10.
16. "Fluoride's predominant effect is posteruptive and topical." MMWR Weekly Report. Vol 50, No. RR-14, August 17, 2001, p. 4.“Fluoride’s caries-preventive properties initially were attributed to changes in enamel during tooth development because of the association between fluoride and cosmetic changes in enamel and a belief that fluoride incorporated into enamel during tooth development would result in a more acid-resistant mineral. However, laboratory and epidemiologic research suggests that fluoride prevents dental caries predominately after eruption of the tooth into the mouth, and its actions primarily are topical for both adults and children.” MMWR Weekly Report. 1999;48:933-940. The CDC also state that the concentration of fluoride in drinking water is too low to have a topical effect. “Studies have shown that even a drop of 0.2 mg/L below the optimum (fluoride) level can reduce dental benefits significantly.” CDC Fluoridation Course 3017-G, pg. 8, para. 3 According to the estimates by CDC, fluoride level for Ontario should be 1.2mg/L. According to CDC’s own calculations, the concentrations (0.5-0.8mg/L) recommended by the MOE are ineffective.
17. Strunecka A, Patocka J, Blaylock RL, Chinoy N. 2007 Fluoride Interactions: From Molecules to Disease. Current Signal Transduction Therapy 2: 190-213.
18. Li L. (2003). The biochemistry and physiology of metallic fluoride: action, mechanism, and implications. Critical Reviews of Oral Biology and Medicine 41(2):100-14.
19. Wittinghofer, A. 1997 Signaling mechanistics: aluminum fluoride for molecule of the year. Current Biology 7:R682-5.
20. Daemker, DM, Dey, DB. Evidence for fluoride effects on salmon passage at John Day Dam, Columbia River 1982-1986, North American Journal of fisheries management, 1989, 9:154-162.
21. Dave G. Effects of fluoride on growth reproduction and survival in Daphnia magna, Comparative Biochemistry and Physiology, 78c(2) 425-431 (1984).

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Joint Response: Health Canada, Public Health Agency of Canada

25 August 2008

James S. Beck, M.D., Ph.D.
4959 Vantage Crescent NW
Calgary, Alberta  T3A 1X6

Dear Dr. Beck:

This is in response to your environmental petition no. 244 of April 18, 2008, addressed to Mr. Ronald C. Thompson, the former Interim Commissioner of the Environment and Sustainable Development (CESD).

In your petition you raised concerns about the addition of fluoridation chemicals to drinking water as it relates to its safety, toxicity and efficacy.

I am pleased to provide you with the enclosed joint Health Canada and Public Health Agency of Canada response to your petition.

I appreciate your interest in this important matter, and I hope that you will find this information useful.

Yours sincerely,

[Original signed by Tony Clement, Minister of Health and the Minister for the Federal Economic Development Initiative for Northern Ontario]

Tony Clement

Enclosure

c.c.  Mr. Scott Vaughan, CESD

---

Response to
Environmental Petition 244 filed by Mr. James S. Beck
under Section 22 of the Auditor General Act
Received April 18, 2008

Petition for the discontinuation of the addition of toxic substances to our drinking water (inorganic fluorides, inorganic arsenic, lead)

August 30, 2008

Minister of Health and the Minister for the Federal Economic
Development Initiative for Northern Ontario

Background:

Health Canada works with the provinces and territories to develop the Guidelines for Canadian Drinking Water Quality. The Guidelines are then used by each province and territory as a basis to establish their own requirements for drinking water quality. Fluoride is one of the many substances for which a guideline has been established. The Maximum Acceptable Concentration (MAC) for fluoride has been established taking into consideration all sources of exposure to fluoride, including foods and dental products. In Canada, the fluoridation of drinking water supplies is a decision that is made by each municipality, in collaboration with the appropriate provincial or territorial authority. This decision may also include consultation with residents, often through a referendum.

Fluoride occurs naturally in many source waters in Canada. It can also be added to drinking water as a public health measure to protect dental health and prevent or reduce tooth decay. The fluoridation of drinking water supplies is a well-accepted measure to protect public health and is strongly supported by scientific evidence. Fluoride is used internationally to protect dental health. It has been added to public drinking water supplies around the world for more than half a century, as a public health/dental health measure. The use of fluoride in the prevention of dental caries continues to be endorsed by over 90 national and international professional health organizations including Health Canada, the Canadian Dental Association, the Canadian Medical Association, the World Health Organization and the Food and Drug Administration of the United States.

As part of its ongoing review of the health effects of exposure to fluoride in drinking water, Health Canada convened a panel of experts in January 2007 to provide advice and recommendations based on the current state of relevant science with respect to the fluoridation of water. Advice was sought from the Expert Panel on five specific issues of concern including Total Daily Intake of Fluoride; Dental Fluorosis; Other Health Effects; Risk Assessment; and Drinking Water Fluoridation: Risks and Benefits. Discussions were based on topic-specific literature reviews developed and presented by some of the invited experts. 

The report produced by the Expert Panel will be used to help inform the development of an updated fluoride guideline for Canadian drinking water, by ensuring our analysis is based on the latest sciencific evidence. The Expert Panel report was posted online and can be found at http://www.hc-sc.gc.ca/ewh-semt/pubs/water-eau/2008-fluoride-fluorure/index-eng.php.

Health Canada will continue to monitor the science and review new scientific reports and articles which explore possible links between fluoride and various health effects to ensure the health of Canadians is protected.

1. What is clearly emerging in the research literature is that fluoride is a toxic substance which should not be ingested. What does Health Canada consider to be a safe daily dosage of fluoride, with an adequate safety margin? Please consider all potential recipients including persons with thyroid disease, persons with kidney disease, infants and children and fetuses. Please show calculations, justifications and references for your determination.

Health Canada uses a population-based approach in the risk assessment process; drinking water guidelines are developed to be protective of the sub-population at greatest risk and are therefore protective of all Canadians. Fluoride is a mineral nutrient used by the human body to maintain dental health. The sub-population most affected by exposure to fluoride is young children aged 22-26 months old, which is also the sub-population used for establishing a drinking water guideline which is protective of all Canadians. There is very limited data to support or refute an increased susceptibility to fluoride in any sub-population other than small children. There are no data to suggest that exposure to fluoride at the Canadian maximum acceptable concentration of 1.5 mg/L would result in adverse effects in these potentially susceptible sub-populations.

2. How can a Canadian citizen determine the daily dose of fluoride from all sources? Please show calculations and references to justify your response.

Determining the daily dose of any specific nutrient from all sources on an individual basis is complicated, as it is dependant on a number of factors such as: the level of fluoride in the water you drink and use for food preparation, and the amount consumed; the amount of fluoride in your foods and the amount consumed; the amount of fluoride in any food supplements or vitamins consumed; etc. If a Canadian citizen is interested in determining their daily dose of fluoride from all sources, they would need to keep a detailed food journal, have access to a laboratory that can analyze their samples and would likely need the support of a qualified professional to help identify all the variables that would affect their daily dose.  

3. Health Canada warns against all intake sources of fluorides from toothpaste, mouthwash, and supplements for young children under 6. Health Canada also warns the public not to give fluoridated dental products to children: “Children under six years of age should be supervised while brushing, and children under the age of three should have their teeth brushed by an adult without using any toothpaste.” “Never give fluoridated mouthwash or mouth rinses to children under six years of age, as they may swallow it.” Health Canada's "Fluoride-Containing Anti-Caries Products Monograph" states that the labels of fluoride containing mouthwashes and toothpastes must carry the following cautionary statement by 2009: "If more than used for brushing is accidentally swallowed, get medical help or contact a Poison Control Centre right away". Why is the pharmaceutical grade fluoride from toothpaste considered to be unsafe and yet the industrial grade fluoride from water is considered to be safe? Please provide references.

The cautionary statements regarding paediatric exposure/ingestion of fluoride that appear in Health Canada's "Fluoride-Containing Anti-Caries Products Monograph" take into account that the pharmaceutical grade may present certain risks depending on the age of the sub-population and how the product is used.  In addition, cautionary statements that speak to the potential for an accidental exposure are considered useful for consumer information purposes since they are better informed and know what to do should such a situation arise.

The references that appear to have been cited further to statements in a Labelling Standard or Monograph (Labelling Standard: Fluoride-containing Treatment Gels and Rinses for Consumer Use. 2003-01-15; Monograph- Fluoride-containing anti-caries products, August 16, 2007), are noted below:

FDA 1995: USA Department of Health and Human Services, Food and Drug Administration. 21 CFR Part 355. Anticaries Drug Products for Over-the-Counter Human Use, Final Monograph. 1995. [Accessed 2007-05-17]. Available at: www.fda.gov/cder/otcmonographs/Anticaries/anticaries(355).pdf

Smith RG. Prevention of hygiene-related oral disorders. In: Berardi RR, DeSimone II EM, Newton GD, Oszko MA, Popovich NG, Rollins CJ, Shimp LA, Tietze KJ, editors. Handbook of Nonprescription Drugs: An Interactive Approach to Self-care, 13th edition. Washington (DC): American Pharmaceutical Association; 2002

CDA 2005b: Canadian Dental Association. CDA Position on Use of Fluorides in Caries Prevention. 2005. [Accessed 2007-05-17]. Available at: www.cda-adc.ca/_files/position_statements/fluorides.pdf

4. "The major dietary source of fluoride for most people in the United States is fluoridated water…” (NRC 2006 p.24) Why does Health Canada not advise against this fluoride source intake for young children?

6. According to Health Canada, prescribing controlled doses of pharmaceutical grade of fluoride, under the care of a doctor is no longer recommended. "Health Canada does not recommend the use of fluoride supplements (drops or tablets). This guideline is consistent with recommendations made by Health Canada's First Nations and Inuit Health Branch (FNIHB) and the Canadian Association of Public Health Dentistry (CAPHD)." (http://www.hc-sc.gc.ca/iyh-vsv/environ/fluor_e.html) Why is the use of uncontrolled doses of hydrofluorosilicic acid, an industrial grade of fluoride which is not regulated by our federal government (it has no DIN) promoted for use in our drinking water in Canada by the Public Health Service and Health Canada when controlled doses of pharmaceutical grade fluorides are not recommended? Does Health Canada believe that administering uncontrolled doses is preferable to controlled doses?

Answer to Questions 4 and 6:

Fluoridated drinking water is not a source of exposure to fluorosilicate compounds such as hydrofluorosilicic acid. When added to water, fluorosilicate compounds readily hydrolyse completely to release fluoride ions, which means that drinking water is not a source of exposure to these compounds. It is also important to note the significant concentrations of fluoride in toothpastes, which are in the range of 1000 to 1500 ppm.

Health Canada has taken into account exposure to fluoride from all sources to determine the maximum acceptable and optimal concentrations in drinking water. For further information, please consult the Guideline Technical Document on Fluoride available on the Health Canada website (http://www.hc-sc.gc.ca/ewh-semt/pubs/water-eau/fluoride-fluorure/index-eng.php).

Water that is optimally fluoridated does not pose a problem with respect to moderate fluorosis for any age group.  Rather, it is the use of fluoride supplements and the ingestion of fluoridated toothpaste during the critical ages that is of concern. As a result, Health Canada recommends the following steps to minimize exposure in small children:

• Never give fluoridated mouthwash or mouth rinses to children under six years of age, as they may swallow it.
• Talk to your dentist before using fluoridated mouthwash.
• Health Canada does not recommend the use of fluoride supplements (drops or tablets). This guideline is consistent with recommendations made by Health Canada's First Nations and Inuit Health Branch (FNIHB) and the Canadian Association of Public Health Dentistry (CAPHD).
• Make sure that your children use no more than a pea-sized amount of toothpaste on their toothbrush, and teach them not to swallow toothpaste. Children under six years of age should be supervised while brushing, and children under the age of three should have their teeth brushed by an adult without using any toothpaste.

For further information, please consult the It’s your Health publication available on the Health Canada website (http//www.hc-sc.gc.ca/hl-vs/iyh-vsv/environ/fluor-eng.php).

5. Does Health Canada believe that one can control the daily dose of fluoride ingested from fluoride in food and beverages? If so, how? If not, how do you justify ignoring such sources? Please show calculations and references to justify your response.

Health Canada has taken into account exposure to fluoride from all sources to determine the maximum acceptable and optimal concentrations in drinking water. For further information, please consult the Guideline Technical Document on Fluoride available on the Health Canada website (http://www.hc-sc.gc.ca/ewh-semt/pubs/water-eau/fluoride-fluorure/index-eng.php). 

7. Examples of high water consumers from NRC 2006 illustrate that many individuals consume more than 5mg/day, while the WHO states that bone effects are expected to occur with such exposure. Does Health Canada consider these individuals to be consuming a safe dose?

It is not appropriate for Health Canada to comment on possible exposures in other countries, particularly as their acceptable levels are much higher than those in place in Canada. Our conclusions are based on internal comprehensive scientific reviews of original relevant scientific studies that are published in internationally recognized peer-reviewed journals.

8. The 2006 Fluoride in Drinking Water: A Scientific Review of EPA’s Standards does a risk assessment which illustrates that many individuals consume more than 0.7mg/day where many (especially women) may be vulnerable to thyroid effects. Does Health Canada disagree with the risk assessment done by the NRC 2006 Committee? If so, on what points and why? If you agree, why does Health Canada insist that recommended concentration levels are safe for everyone? Please provide references you use to come to your conclusions.

As stated earlier, Health Canada uses a population-based approach in risk assessment and therefore establishes drinking water guidelines based on the sub-population likely to be most affected. The sub-population most affected by exposure to fluoride is young children aged 22-26 months old, which is also the sub-population used for establishing a drinking water guideline which is protective of all Canadians. There are no data to suggest that exposure to fluoride at the Canadian maximum acceptable concentration of 1.5 mg/L would result in adverse effects for those consuming larger quantities of drinking water.  

It is not appropriate for Health Canada to comment on the opinion or position of individuals or agencies. Health Canada’s conclusions are based on internal comprehensive scientific reviews of original relevant scientific studies that are published in internationally recognized peer-reviewed journals.