Frequently Asked Questions

What is community water fluoridation?

Community water fluoridation is the adding of the fluoride ion to water supplies to achieve an optimum fluoride concentration of 0.7 – 1.2 parts per million (ppm)*. Some locations in the US have fluoride naturally occurring in their water. These places may not require fluoride to be added to their water supplies to achieve the optimal fluoridation level. It is also possible that the naturally occurring fluoridated water may be too high in its fluoride concentration, and the water may need to monitored and adjusted so that the fluoride concentration does not exceed the optimum levels. Most of the water supplies in Louisiana do not have naturally occurring fluoride and thus need fluoride to be added to achieve optimal levels (American Dental Association, 2005).

*You may also see fluoride concentrations expressed as mg/L; 1 ppm = 1 mg/L

Why is community fluoridation important?

Fluoridating drinking water is a safe, practical, effective, and cost efficient method to prevent tooth decay and cavities (U.S. Department of Health and Human Services, 2000). Fluoridating water benefits all who drink the water, regardless of age, gender, race, economic status, or education. Additionally, fluoride benefits those who are not able to access dental care, or who do not access dental care regularly (Centers for Disease Control, 2005).

How does fluoride in the drinking water prevent cavities?

Firstly, when your teeth are developing, the fluoride is deposited into the tooth surface making it stronger and providing long-lasting protection against decay.

Secondly, when you eat foods, food particles get stuck between teeth and between the teeth and the gums. These food particles have sugars that bacteria consume. All foods have sugars, even fruits and vegetables, not just sweets like cookies and candies. When the bacteria eat the sugars lactic acid is released, which causes the mouth's over all pH to be lowered to a point where the enamel of the teeth can begin to break down. If the enamel is broken down at a faster rate than it can be repaired, cavities will develop. Enamel repair, called remineralization, is aided by fluoride. Fluoride ions are able to repair some of the broken molecules in the enamel, and it also enhances the deposition of calcium and phosphate, both of which are needed for remineralization.


What if I don’t like to drink water?

If you are using fluoridated water in your home for food preparation you are ingesting fluoride. If you use fluoridated water for preparing beverages, like juices from concentrate or coffee, you are ingesting fluoride. Food and beverage items produced in fluoridated communities can also introduce the benefits of fluoride to non-fluoridated communities (known as a halo-effect) (American Dental Association, 2005).

Doesn’t my toothpaste have fluoride already?

Yes. Most toothpastes sold in the US do contain fluoride. The concentration of fluoride in toothpastes is significantly higher than that of water, starting at or around 1000 ppm. This is why it is so important for parents to supervise their children when using fluoridated toothpastes.

Certain mouth rinses also have fluoride. Fluoride concentrations for mouth rinses generally range from 230 ppm to 920 ppm.

There are also fluoride treatments, similar to those done at the dentist office that can be done at home. These treatments have fluoride concentrations anywhere from 1000 ppm to 12300 ppm (Centers for Disease Control, 2008).


If my toothpaste already has fluoride, why does my drinking water need it too?

Not everyone is able to brush as often or as adequately as is recommended. Fluoridated water, therefore, is a method of providing a level of fluoride that is helpful in fighting tooth decay in times when brushing is not possible. Additionally, not everyone is able to acquire or afford the fluoridated mouth rinses, at home treatments, or even visit a dentist regularly. Fluoridated water is of tremendous benefit to these individuals.

Is there anything I should be worried about with fluoride or fluoridated water?

The optimum fluoride concentration for fluoridated water is 0.7 –1.2 ppm. The Environmental Protection Agency (EPA) Safe Drinking Water Act has set 4.0 ppm as the maximum contaminant level (MCL) for fluoride.  To ensure the safety of the public, fluoride concentrations cannot exceed the maximum contaminant level (American Dental Association, 2005). It is unlikely that routine daily life exposure to fluoride through water, food and beverage products, and recommended daily oral health practices, like brushing your teeth, would cause excessive fluoride exposure.

As mentioned above topical fluoride methods, like toothpaste and mouth rinses, contain significantly higher levels of fluoride than drinking water.  To prevent accidental ingestion of too much fluoride, parents should monitor their children when their children are using these products (Centers for Disease Control, 2008).