Know Your Environment. Protect Your Health.

Fluoride

Arlington Waterworks

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.

 

71

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.628 ppm26260.257 ppm - 0.800 ppm
20190.693 ppm24240.582 ppm - 0.858 ppm
20200.611 ppm19190.0716 ppm - 1.46 ppm
20210.0970 ppm110.0970 ppm
2022N/A00N/A
2023ND10ND

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
2018-01-023609120010.257 ppm
2018-01-023609120010.600 ppm
2018-02-083661780010.800 ppm
2018-02-083661780010.349 ppm
2018-03-053696360010.286 ppm
2018-03-053696360010.750 ppm
2018-03-093703130010.460 ppm
2018-03-093703130010.344 ppm
2018-04-023737380010.776 ppm
2018-04-023737380010.800 ppm
2018-05-013794190010.695 ppm
2018-05-013794190010.700 ppm
2018-06-113873680010.784 ppm
2018-06-113873680010.680 ppm
2018-07-023917660010.714 ppm
2018-07-023917660010.670 ppm
2018-08-063986000010.760 ppm
2018-08-063986000010.757 ppm
2018-09-044045440010.700 ppm
2018-09-044045440010.657 ppm
2018-10-014112350010.674 ppm
2018-10-014112350010.600 ppm
2018-11-054175690010.640 ppm
2018-11-054175690010.557 ppm
2018-12-034219040010.740 ppm
2018-12-034219040010.582 ppm
2019-01-034259700010.639 ppm
2019-01-034259700010.710 ppm
2019-02-144314170010.582 ppm
2019-02-144314170010.620 ppm
2019-03-014332330010.659 ppm
2019-03-014332330010.670 ppm
2019-04-014377390010.684 ppm
2019-04-014377390010.690 ppm
2019-05-014431760010.701 ppm
2019-05-014431760010.700 ppm
2019-06-044494350010.660 ppm
2019-06-044494350010.680 ppm
2019-07-014547420010.650 ppm
2019-07-014547420010.669 ppm
2019-08-014608300010.670 ppm
2019-08-014608300010.710 ppm
2019-09-034669560010.690 ppm
2019-09-034669560010.702 ppm
2019-10-044744710010.730 ppm
2019-10-044744710010.858 ppm
2019-11-014791070010.750 ppm
2019-11-014791070010.823 ppm
2019-12-024836020010.679 ppm
2019-12-024836020010.700 ppm
2020-01-024875890010.609 ppm
2020-01-024875890010.680 ppm
2020-04-024993040010.714 ppm
2020-04-024993040010.690 ppm
2020-05-015026680010.700 ppm
2020-05-015026680010.714 ppm
2020-06-015074090010.720 ppm
2020-06-015074090010.759 ppm
2020-06-254385090.180 ppm
2020-07-095137980010.740 ppm
2020-07-095137980010.892 ppm
2020-08-275221860011.46 ppm
2020-08-275221860010.689 ppm
2020-10-015287980010.0716 ppm
2020-10-015287980010.1000 ppm
2020-10-225326620010.442 ppm
2020-10-225326620010.680 ppm
2020-11-115356660010.316 ppm
2020-11-115356660010.450 ppm
2021-05-1212535270.0970 ppm
2023-04-191314807ND