Know Your Environment. Protect Your Health.

Fluoride

Mountain Regional Water Special Service 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.

 

33

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.166 ppm440.142 ppm - 0.188 ppm
20190.102 ppm127ND - 0.430 ppm
20200.106 ppm32ND - 0.200 ppm
20210.112 ppm110.112 ppm
20220.0892 ppm126ND - 0.394 ppm
20230.133 ppm110.133 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 Result
2018-06-060.188 ppm
2018-06-200.165 ppm
2018-08-230.142 ppm
2018-09-050.170 ppm
2019-01-03ND
2019-01-030.120 ppm
2019-01-030.189 ppm
2019-01-030.116 ppm
2019-01-240.110 ppm
2019-01-240.133 ppm
2019-01-24ND
2019-02-250.430 ppm
2019-02-25ND
2019-02-25ND
2019-03-200.120 ppm
2019-11-14ND
2020-02-270.200 ppm
2020-07-14ND
2020-09-210.119 ppm
2021-12-080.112 ppm
2022-02-17ND
2022-02-170.163 ppm
2022-02-17ND
2022-02-170.145 ppm
2022-05-050.132 ppm
2022-05-050.394 ppm
2022-05-050.128 ppm
2022-08-04ND
2022-08-04ND
2022-08-04ND
2022-09-07ND
2022-12-070.109 ppm
2023-12-110.133 ppm