What is fluoridation in drinking water?

What is fluoridation?

Fluoridation is the process of adjusting the amount of fluoride in drinking water to a level recommended for preventing cavities, according to the American Dental Association (ADA).

According to the U.S. Centers for Disease Control (CDC), it is a practical, cost-effective and equitable way for communities to improve their residents’ oral health regardless of age, education or income.[1]

What is the history of flouridation in drinking water?

In 1945 Grand Rapids, Michigan, became the first city to add fluoride to its water supply following a fluoridation pilot project. According to the Harvard T.H. Chan School of Public Health, this came after scientists linked high levels of naturally occurring flouride in certain communities with low levels of tooth decay.

Throughout the 1950s and 60s, communities across the U.S. began fluoridating their water, and tooth decay rates dropped significantly as a result, states a Children's Dental Health Project article.

The United States Public Health Service (PHS), in 1962, recommended that public water supplies contain fluoride to help prevent tooth decay. In the same year, federal drinking water standards were updated, including fluoride guidelines with recommended and maximum levels.

These recommendations, at a federal level, remianed the same throughout the creation of the EPA, the Clean Water Act and Safe Drinking Water Act until 2015 when new guidance was suggested advising water systems adopt uniform concentrations of 0.7 mg/L (0.7 ppm).

On Sept. 24, a federal court ordered U.S. EPA to take regulatory action to mitigate "unreasonable risk" from fluoridation to the health of children. Plaintiffs in the case presided by the federal court argued fluoridation posed a risk to neurodevelopment in children.

How does fluoridation work?

Fluoride occurs naturally in most groundwater sources, but usually at levels too low to prevent cavities.

According to the CDC, the recommended fluoride concentration in drinking water (also known as the optimal level) is 0.7 mg of fluoride per liter of water (or 0.7 parts per million (ppm)). This is equal to about 3 drops in a 55-gallon barrel.

The U.S. Environmental Protection Agency (EPA) has set upper limits on the amount of fluoride allowed in drinking water in the form of a Maximum Contaminant Level (MCL) and Maximum Contaminant Level goal (MLCG). Both are set at 4.0 mg/L (4.0 ppm).

The secondary MCLG (SMCLG) of 2.0 mg/L (2.0 ppm) has been set for fluoride to minimize potential dental fluorosis.[2]

It is up to state and local governments to determine whether to implement water fluoridation.

Some states have laws that require water systems of certain sizes to provide fluoridated water to their customers. In some areas, the level of naturally occurring fluoride in water is already at a level proven to prevent cavities.

If a state require fluoridation, water systems can add or remove fluoride as needed to meet the optimum levels.

Is fluoride in drinking water safe?

The ADA states in a fluoridation facts sheet that the overwhelming weight of scientific evidence supports the safety of community water fluoridation.[3]

The ADA states that studies have continued since the inception of fluoridation to determine the effects of fluorides in humans. Studies have determined that fluoride in drinking water is safe and effective when used and consumed in the recommended doses.

Throughout history, humans have lived in areas where fluoride is found naturally in drinking water in concentrations as high or higher than optimal levels.

Through ongoing research agencies such as the U.S. Department of Health and Human Services and the EPA have updated important steps, standards and guidelines over the years.

In 2015, the U.S. Public Health Service issued a report recommending 0.7 mg/L (0.7 ppm) as the optimal level of fluoride in drinking water for all temperature zones in the U.S.

Changes can occur due to continual research and information that is emerging and being disseminated. Government agencies such as the U.S. National Institutes of Health, National Institute of Dental and Craniofacial Research and others continue to fund fluoride research.

According to the Texas Department of State Health Services, not only is fluoridation safe, but it’s the most cost-effective way to deliver fluoride to everyone. On average, it costs $0.64 per person to fluoridate water for a year. For most cities, every $1 invested in water fluoridation yields $38 savings in dental treatment costs. [4]

What are the disadvantages of fluoride in water?

According to the Cleveland Clinic, fluoride is safe and effective when used properly, but it can be hazardous at high doses. The most common side effect of fluoride is fluorosis.

Fluorosis is fluoride-induced tooth discoloration.[5]

People with fluorosis develop spots on their teeth that can range from light white to dark brown. These spots usually occur during tooth development.

Fluorosis most often results from consuming naturally occurring fluoride, like that found in well water.

According to a study titled “Fluoride occurrences, health problems, detection, and remediation methods for drinking water: A comprehensive review,” excess amounts of fluoride ions in drinking water can cause dental fluorosis, skeletal fluorosis, arthritis, bone damage, osteoporosis, muscular damage, fatigue, joint-related problem, and chronicle issues.

The study states that in extreme conditions, it could adversely damage the heart, arteries, kidney, liver, endocrine glands, neuron system and several other delicate parts of a living organism.[6]

Harmony Dental, out of Texas, lists similar side effects, but all are attributed to excess levels of fluoride.[7]