Know Your Environment. Protect Your Health.

Fluoride

Metropolitan Utilities District

Fluoride occurs naturally in surface and groundwater and is also added to drinking water by many water systems to prevent cavities and support oral health in people.

In 2015, the Department of Health and Human Services updated its recommendation of an optimal level of 0.7 parts per million, or ppm, added to drinking water based on the health benefits of tooth decay prevention. Studies have shown that fluoride added to community water systems at this level reduces dental cavities, especially in children.

And studies have conclusively shown that fluoride in toothpaste and mouthwash can also provide these benefits. Read More.

Health Concerns

Although the HHS-recommended level of 0.7 ppm can help promote oral health in children and adults, this level is likely too high for bottle-fed babies. EWG recommends that caregivers mix baby formula with fluoride-free water.

And fluoride in water at higher levels can be detrimental for everyone, especially children.

Long-term ingestion of higher levels of fluoride in water increases dental fluorosis, which includes mottling, pitting and weakening of the teeth in children.

A 2024 authoritative assessment by the National Toxicology Program found that higher levels of fluoride exposure, such as drinking water containing more than 1.5 ppm of fluoride, are associated with lower IQ in children. The conclusion was based on studies in human populations outside of the U.S.

Affecting systems with naturally occurring fluoride, EPA’s maximum legal limit is set at 4 parts per million (ppm) to prevent skeletal fluorosis, a condition where bones become brittle and more susceptible to fracture. But these effects may occur at lower levels of exposure, raising concerns that the current limit may not adequately protect public health.

 

52

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.691 ppm12120.352 ppm - 0.868 ppm
20190.658 ppm1514ND - 0.924 ppm
20200.544 ppm17170.238 ppm - 0.850 ppm
20210.665 ppm440.631 ppm - 0.738 ppm
20220.696 ppm220.694 ppm - 0.697 ppm
20230.466 ppm220.270 ppm - 0.662 ppm

ppm = parts per million

State, National, and Health Guidelines for Drinking Water

EPA Maximum Contaminant
Level (MCL): 4 ppm

ppm = parts per million

All test results

Date Lab ID Result
2018-01-025301900.776 ppm
2018-02-135357650.762 ppm
2018-03-125392460.781 ppm
2018-04-045425380.744 ppm
2018-05-085487610.352 ppm
2018-06-115539830.649 ppm
2018-07-105586420.356 ppm
2018-08-135663920.868 ppm
2018-09-115705940.843 ppm
2018-10-015765320.677 ppm
2018-11-195820280.718 ppm
2018-12-045858550.762 ppm
2019-01-075892750.755 ppm
2019-02-045947040.761 ppm
2019-03-045981050.726 ppm
2019-04-086019720.526 ppm
2019-05-146095920.683 ppm
2019-06-10603528ND
2019-06-106035270.683 ppm
2019-06-106135060.712 ppm
2019-07-086194930.682 ppm
2019-07-156221410.684 ppm
2019-08-136272840.924 ppm
2019-09-096314950.699 ppm
2019-10-156367690.737 ppm
2019-11-056435130.672 ppm
2019-12-106482550.632 ppm
2020-01-146526660.725 ppm
2020-02-196574050.687 ppm
2020-03-096610750.253 ppm
2020-04-206660550.238 ppm
2020-05-056710020.269 ppm
2020-05-206688350.770 ppm
2020-05-206688340.258 ppm
2020-05-206688310.320 ppm
2020-05-206688320.263 ppm
2020-05-206688330.313 ppm
2020-06-096770400.788 ppm
2020-07-136808460.850 ppm
2020-08-106888690.708 ppm
2020-09-096941530.704 ppm
2020-10-066982730.720 ppm
2020-11-047054940.711 ppm
2020-12-147096590.670 ppm
2021-01-127137970.640 ppm
2021-02-087190270.651 ppm
2021-03-027233060.738 ppm
2021-04-127256200.631 ppm
2022-04-117929200.694 ppm
2022-07-118100120.697 ppm
2023-01-178448300.270 ppm
2023-04-058557710.662 ppm