Elevated Fluoride Levels

Subject: Central Zone Water Systems (including Rumsey Waterworks) with Elevated Fluoride Levels-- Information for Operators and Water System Users

Dear Operator and Water System Users:

Alberta Health Services (AHS) Central Zone is aware that the water supplied by this system contains naturally occurring fluoride at 2.0 mg/L, based on sampling which occurred on February 2025. This level is greater than the maximum acceptable concentration (MAC) for fluoride set by Health Canada of 1.5 mg/L for drinking water (water used for drinking and food preparation).

This letter provides information about the health effects of fluoride and makes recommendations about the use of water with fluoride levels above the MAC for drinking, handwashing, and bathing, as well as recommendations about ongoing testing. Information about the safe use of other sources of fluoride to maintain dental health is also included.

What is fluoride and what are its health effects?

Fluoride is a naturally occurring mineral that plays an important role in keeping teeth healthy. As fluoride occurs naturally in the earth’s surface, all well water, ground water, and lakes and rivers have some level of fluoride.

Small amounts of fluoride, up to 0.7 mg/L, are added to some community water supplies with low levels of naturally occurring fluoride to help prevent tooth decay and maintain good dental health. However, levels above 1.5 mg/L may cause dental fluorosis.

Mild dental fluorosis looks like white flecks on the teeth and may be difficult to notice; however, teeth with moderate or severe fluorosis have large white patches and may have rough enamel or stains. These changes only happen while the teeth are developing under the gum in children under 9 years of age. Fluorosis will not be seen until adult teeth erupt into the mouth, up to 5 or 6 years after consuming the water with a high fluoride level. Afterwards, there is no more risk of dental fluorosis.

Although rare in Canada, exposure to high levels of fluoride in drinking water over long periods of time may result in skeletal fluorosis. Skeletal fluorosis results in fluoride being deposited in bones, causing them to become more dense and at greater risk of fracture. It can also lead to the calcification of ligaments, joints, and vertebrae, in turn leading to arthritis and reduced mobility.

Exposure to very high levels of fluoride can cause acute toxicity, including fatigue, gastrointestinal, neurologic, and cardiac signs and symptoms, and potentially, death.

There is no risk of moderate dental fluorosis, skeletal fluorosis, or acute toxicity if drinking water concentrations do not exceed 1.5 mg/L.

Recommendations

Drinking Water Uses, Fluoride Reduction, and Testing

1. Use water with no more than 1.5 mg/L of fluoride:

  • To mix baby formula and in the preparation of other drinks.
  • For regular drinking and cooking.

2. Ways to reduce fluoride concentration to 1.5 mg/L or less:

  • Use only bottled water; check the label to make sure it contains no more than 1.5 mg/L.
  • Mix tap water with bottled water to reduce concentration to no more than 1.5 mg/L.
  • Use treatments such as reverse-osmosis, distillation, or activated alumina.

− Consult the documentation included with any treatment device to confirm that fluoride is removed and to determine maintenance procedures.

− NSF-certified products are recommended. − Pour-through or pitcher-type filters do not remove fluoride.

− Consider both installation and maintenance costs, and test following installation.

3. Breastfeeding or chestfeeding by persons drinking water with fluoride levels at 1.5mg/L or less is safe, since only small amounts of fluoride are transferred to infants by this route.

4. Handwashing and bathing are safe because skin absorption from contact with drinking water is expected to be low.

5. Systems regulated by AHS and private drinking water systems are eligible to test their chemical water quality every three years at no charge through the Alberta Center for Toxicology. Systems licensed by Alberta Environment and Protected Areas (EPA) have specified sampling requirements ranging from annually to quarterly

Safe Use of Other Sources of Fluoride to Maintain Dental Health

6. Supervise toothpaste use for children:

  • Caregivers should apply the toothpaste to the toothbrush and ensure the child’s teeth are brushed thoroughly twice a day.
  • Toothpaste is not meant to be ingested. To minimize ingesting toothpaste, children should be taught to spit and not swallow.
  • From first tooth to 3 years, it is recommended that caregivers use a grain-of-rice-size amount of fluoride toothpaste to brush children’s teeth.
  • For children 3 years and older, it is recommended that caregivers use a pea-size amount of fluoride toothpaste.

7. Avoid giving fluoride mouth rinse to children younger than 6 years old (risk of swallowing).

  • Most children over 6 years of age can be instructed not to swallow, but parental supervision is still recommended.

8. Inform your dentist and dental hygienist of your drinking water fluoride content. Maintain regular dental check-ups and preventive fluoride therapies as advised by your dental office or by the oral health program AHS. Fluoride therapies used properly (gels, foams, and varnishes) do not contribute to the risk of dental fluorosis.

More Information on Fluoride in Drinking Water

You may also contact your local AHS Public Health Inspector at: 1-833-476-4743.

Sincerely,

Dr. Digby Horne, MD

Medical Officer of Health

Alberta Health Services, Central Zone

cc: Pamela Kutuadu, Public Health Inspector, AHS Jesse Skwaruk, Drinking Water Operational Specialist, EPA

Medical Officers of Health, Central Zone 300 Jordan Parkway Red Deer, Alberta T4P 0G8

2025-03-25-Rumsey-Waterworks-System-Elevated-Fluoride-Letter.pdf