Know Your Environment. Protect Your Health.

Fluoride

Gilbert Water Works

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.

 

39

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.690 ppm220.680 ppm - 0.700 ppm
20190.498 ppm43ND - 0.850 ppm
20200.308 ppm84ND - 1.04 ppm
2021ND10ND
20220.245 ppm119ND - 0.510 ppm
20230.254 ppm1311ND - 0.520 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
2018-04-1618042000-03A0.680 ppm
2018-07-1118071425-02A0.700 ppm
2019-04-1719042259-04A0.310 ppm
2019-05-1519051937-01A0.830 ppm
2019-09-1119091642-03A0.850 ppm
2019-12-129120364-01ND
2020-01-160011286-01ND
2020-01-160011286-01ND
2020-02-130020466-01ND
2020-02-130020466-01ND
2020-03-120030236-011.04 ppm
2020-04-160041000-010.540 ppm
2020-05-140050485-010.250 ppm
2020-10-080100291-010.630 ppm
2021-11-111110289-01ND
2022-05-122050415-010.510 ppm
2022-05-122050415-020.480 ppm
2022-05-122050416-010.370 ppm
2022-06-162060295-010.180 ppm
2022-07-142073904-01ND
2022-07-142070384-01ND
2022-08-112080382-010.200 ppm
2022-09-082090208-010.200 ppm
2022-10-132100199-010.210 ppm
2022-11-102110299-010.310 ppm
2022-12-082120278-010.230 ppm
2023-01-123010178-010.120 ppm
2023-02-093020197-01ND
2023-03-093030206-010.140 ppm
2023-04-133040254-010.520 ppm
2023-05-093050440-010.230 ppm
2023-06-133060170-010.250 ppm
2023-07-133070274-010.440 ppm
2023-07-133100011-010.430 ppm
2023-08-103080388-010.330 ppm
2023-09-143090279-010.320 ppm
2023-10-123100341-01ND
2023-11-093110331-010.320 ppm
2023-12-143120286-010.200 ppm