Know Your Environment. Protect Your Health.

Fluoride

Cornell 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.

 

148

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.767 ppm24240.660 ppm - 0.844 ppm
20190.706 ppm24240.610 ppm - 0.790 ppm
20200.663 ppm21210.600 ppm - 0.740 ppm
20210.673 ppm28280.620 ppm - 0.770 ppm
20220.693 ppm26260.610 ppm - 0.780 ppm
20230.701 ppm25250.660 ppm - 0.770 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
2018-01-163631530010.730 ppm
2018-01-163631530010.815 ppm
2018-02-213682060010.720 ppm
2018-02-213682060010.796 ppm
2018-03-143714220010.660 ppm
2018-03-143714220010.781 ppm
2018-04-183772660010.780 ppm
2018-04-183772660010.834 ppm
2018-05-163830250010.720 ppm
2018-05-163830250010.775 ppm
2018-06-273915250010.680 ppm
2018-06-273915250010.809 ppm
2018-07-183956520010.690 ppm
2018-07-183956520010.806 ppm
2018-08-294043170010.758 ppm
2018-08-294043170010.760 ppm
2018-09-194093990010.780 ppm
2018-09-194093990010.818 ppm
2018-10-244164480010.710 ppm
2018-10-244164480010.794 ppm
2018-11-214209210010.780 ppm
2018-11-214209210010.844 ppm
2018-12-124243010010.750 ppm
2018-12-124243010010.819 ppm
2019-01-234290010010.776 ppm
2019-01-234290010010.790 ppm
2019-02-204325730010.721 ppm
2019-02-204325730010.740 ppm
2019-03-274375620010.704 ppm
2019-03-274375620010.750 ppm
2019-04-174412780010.710 ppm
2019-04-174412780010.730 ppm
2019-05-224478370010.674 ppm
2019-05-224478370010.740 ppm
2019-06-194531060010.675 ppm
2019-06-194531060010.770 ppm
2019-07-244599150010.640 ppm
2019-07-244599150010.670 ppm
2019-08-214654990010.667 ppm
2019-08-214654990010.700 ppm
2019-09-184713620010.692 ppm
2019-09-184713620010.760 ppm
2019-10-094757310010.686 ppm
2019-10-094757310010.730 ppm
2019-11-064804820010.670 ppm
2019-11-064804820010.720 ppm
2019-12-114858550010.610 ppm
2019-12-114858550010.630 ppm
2020-01-154896920010.639 ppm
2020-01-154896920010.680 ppm
2020-04-085003340010.660 ppm
2020-04-085003340010.740 ppm
2020-05-135048430010.652 ppm
2020-05-135048430010.700 ppm
2020-06-175104480010.666 ppm
2020-06-175104480010.700 ppm
2020-07-155151530010.636 ppm
2020-07-155151530010.700 ppm
2020-08-125198260010.627 ppm
2020-08-125198260010.700 ppm
2020-09-165263250010.600 ppm
2020-09-165263250010.635 ppm
2020-09-2212168000.670 ppm
2020-10-145314540010.640 ppm
2020-10-145314540010.647 ppm
2020-11-045348160010.658 ppm
2020-11-045348160010.660 ppm
2020-12-025385680010.650 ppm
2020-12-025385680010.661 ppm
2021-01-135438800010.670 ppm
2021-01-135438800010.770 ppm
2021-02-105473380010.620 ppm
2021-02-105473380010.688 ppm
2021-02-105473380010.620 ppm
2021-02-105473380010.688 ppm
2021-03-105514210010.675 ppm
2021-03-105514210010.720 ppm
2021-03-105514210010.675 ppm
2021-03-105514210010.720 ppm
2021-04-075554050010.680 ppm
2021-04-075554050010.750 ppm
2021-05-125616350010.640 ppm
2021-05-125616350010.660 ppm
2021-06-095663700010.638 ppm
2021-06-095663700010.760 ppm
2021-07-075711550010.630 ppm
2021-07-075711550010.634 ppm
2021-08-115780120010.660 ppm
2021-08-115780120010.660 ppm
2021-09-085825610010.640 ppm
2021-09-085825610010.648 ppm
2021-10-135898190010.646 ppm
2021-10-135898190010.710 ppm
2021-11-035931360010.620 ppm
2021-11-035931360010.666 ppm
2021-12-085979320010.676 ppm
2021-12-085979320010.680 ppm
2022-01-126019970010.610 ppm
2022-01-126019970010.675 ppm
2022-02-096055700010.696 ppm
2022-02-096055700010.780 ppm
2022-03-026079570010.727 ppm
2022-03-026079570010.780 ppm
2022-04-066129370010.712 ppm
2022-04-066129370010.740 ppm
2022-05-116194300010.702 ppm
2022-05-116194300010.710 ppm
2022-06-086243010010.690 ppm
2022-06-086243010010.750 ppm
2022-07-206324200010.644 ppm
2022-07-206324230010.656 ppm
2022-07-206324200010.680 ppm
2022-07-206324230010.690 ppm
2022-08-176378390010.628 ppm
2022-08-176378390010.670 ppm
2022-09-146429150010.650 ppm
2022-09-146429150010.716 ppm
2022-10-056471460010.640 ppm
2022-10-056471460010.659 ppm
2022-11-026515860010.640 ppm
2022-11-026515860010.713 ppm
2022-12-076563830010.702 ppm
2022-12-076563830010.760 ppm
2023-01-116605540010.670 ppm
2023-01-116605540010.676 ppm
2023-02-016628970010.680 ppm
2023-02-016628970010.687 ppm
2023-03-076675240010.696 ppm
2023-03-076675240010.750 ppm
2023-04-056717740010.713 ppm
2023-04-056717740010.770 ppm
2023-05-036767300010.662 ppm
2023-05-036767300010.740 ppm
2023-05-16CB05110-010.660 ppm
2023-06-076827510010.694 ppm
2023-06-076827510010.730 ppm
2023-07-056872570010.670 ppm
2023-07-056872570010.721 ppm
2023-08-026928270010.686 ppm
2023-08-026928270010.700 ppm
2023-09-066990440010.693 ppm
2023-09-066990440010.700 ppm
2023-10-097058920010.680 ppm
2023-10-097058920010.714 ppm
2023-11-017090130010.720 ppm
2023-11-017090130010.757 ppm
2023-12-067138760010.680 ppm
2023-12-067138760010.681 ppm