Fluoride is present in virtually all waters at some level and it is important to know the fluoride content of your water, particularly if you have children. To find out the fluoride concentration in your well water, it would need to be analyzed by a laboratory. Your public health department should be able to advise how to have your home well water tested. Additional information on testing well water quality in private wells serving homes can be found on the U.S. Environmental Protection Agency Web siteExternal.
The recommended fluoride level in drinking water for good oral health is 0.7 mg/L (milligrams per liter). If fluoride levels in your drinking water are lower than 0.7 mg/L, your child’s dentist or pediatrician should evaluate whether your child could benefit from daily fluoride supplements. Their recommendation will depend on your child’s risk of developing tooth decay, as well as exposure to other sources of fluoride, such as drinking water at school or daycare, and fluoride toothpaste. It is not currently feasible to add fluoride to an individual residence’s well.
In some regions in the United States, community drinking water and home wells can contain levels of naturally occurring fluoride that are greater than the level recommended by the US Public Health Service for preventing tooth decay. The U.S. Environmental Protection Agency (EPA) currently has a non-enforceable recommended guideline for fluoride of 2.0 mg/L that is set to protect against dental fluorosis. If your home is served by a water system that has fluoride levels exceeding this recommended guideline, EPA recommends that children 8 years and younger be provided with alternative sources of drinking water.
It is unusual to have the fluoride content of water be 4 mg/L or higher. If a laboratory report indicates that you have such a high fluoride content, we recommend that you retest the water. You should collect at least four samples over four weeks (one sample each week), and compare the results. If one sample is above 4 mg/L and the other samples are less than 4 mg/L, then the high value may have been an error. If the results for all the samples show levels greater than 4 mg/L, you may want to consider alternate sources of water for drinking and cooking, or installing a device to remove the fluoride from your home water source. Physical contact with water with a high fluoride content, such as through bathing or washing dishes, is safe since fluoride does not pass through the skin.