Fluoride
Muscoda 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.
Samples
Samples exceeding legal limit (MCL)
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2018 | 1.08 ppm | 24 | 24 | 0.807 ppm - 1.37 ppm |
| 2019 | 1.12 ppm | 24 | 24 | 0.973 ppm - 1.32 ppm |
| 2020 | 0.858 ppm | 22 | 22 | 0.0500 ppm - 1.25 ppm |
| 2021 | 0.778 ppm | 29 | 29 | 0.120 ppm - 1.08 ppm |
| 2022 | 0.695 ppm | 24 | 24 | 0.504 ppm - 0.830 ppm |
| 2023 | 0.554 ppm | 26 | 26 | 0.110 ppm - 0.840 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 |
|---|---|---|
| 2018-01-08 | 361983001 | 0.957 ppm |
| 2018-01-08 | 361983001 | 1.23 ppm |
| 2018-02-13 | 366984001 | 1.000 ppm |
| 2018-02-13 | 366984001 | 1.04 ppm |
| 2018-03-19 | 371910001 | 1.02 ppm |
| 2018-03-19 | 371910001 | 1.22 ppm |
| 2018-04-09 | 375386001 | 1.06 ppm |
| 2018-04-09 | 375386001 | 1.18 ppm |
| 2018-05-14 | 382160001 | 0.996 ppm |
| 2018-05-14 | 382160001 | 1.11 ppm |
| 2018-06-20 | 390081001 | 0.829 ppm |
| 2018-06-20 | 390081001 | 1.16 ppm |
| 2018-07-10 | 393610001 | 0.807 ppm |
| 2018-07-10 | 393610001 | 0.960 ppm |
| 2018-08-01 | 398195001 | 1.02 ppm |
| 2018-08-01 | 398195001 | 1.20 ppm |
| 2018-09-17 | 408405001 | 1.08 ppm |
| 2018-09-17 | 408405001 | 1.22 ppm |
| 2018-10-15 | 414651001 | 1.04 ppm |
| 2018-10-15 | 414651001 | 1.21 ppm |
| 2018-11-14 | 420130001 | 1.13 ppm |
| 2018-11-14 | 420130001 | 1.37 ppm |
| 2018-12-12 | 424238001 | 1.02 ppm |
| 2018-12-12 | 424238001 | 1.11 ppm |
| 2019-01-09 | 427255001 | 1.02 ppm |
| 2019-01-09 | 427255001 | 1.16 ppm |
| 2019-02-26 | 433076001 | 1.08 ppm |
| 2019-02-26 | 433076001 | 1.31 ppm |
| 2019-03-25 | 437109001 | 1.07 ppm |
| 2019-03-25 | 437109001 | 1.20 ppm |
| 2019-04-22 | 441778001 | 1.000 ppm |
| 2019-04-22 | 441778001 | 1.000 ppm |
| 2019-05-08 | 445110001 | 1.14 ppm |
| 2019-05-08 | 445110001 | 1.32 ppm |
| 2019-06-05 | 450217001 | 1.02 ppm |
| 2019-06-05 | 450217001 | 1.21 ppm |
| 2019-07-17 | 458397001 | 0.980 ppm |
| 2019-07-17 | 458397001 | 1.02 ppm |
| 2019-08-15 | 464189001 | 1.05 ppm |
| 2019-08-15 | 464189001 | 1.09 ppm |
| 2019-09-09 | 468731001 | 1.08 ppm |
| 2019-09-09 | 468731001 | 1.26 ppm |
| 2019-10-01 | 473961001 | 1.10 ppm |
| 2019-10-01 | 473961001 | 1.18 ppm |
| 2019-11-05 | 480036001 | 1.05 ppm |
| 2019-11-05 | 480036001 | 1.28 ppm |
| 2019-12-11 | 485823001 | 0.973 ppm |
| 2019-12-11 | 485823001 | 1.29 ppm |
| 2020-01-09 | 488762001 | 1.03 ppm |
| 2020-01-09 | 488762001 | 1.18 ppm |
| 2020-04-13 | 20D0406-01 | 0.0500 ppm |
| 2020-04-13 | 20D0406-02 | 0.0800 ppm |
| 2020-04-14 | 501002001 | 1.14 ppm |
| 2020-04-14 | 501002001 | 1.25 ppm |
| 2020-05-11 | 504261001 | 0.990 ppm |
| 2020-05-11 | 504261001 | 1.09 ppm |
| 2020-06-24 | 511583001 | 1.03 ppm |
| 2020-06-24 | 511583001 | 1.10 ppm |
| 2020-07-21 | 516087001 | 0.718 ppm |
| 2020-07-21 | 516087001 | 0.950 ppm |
| 2020-08-25 | 521986001 | 0.670 ppm |
| 2020-08-25 | 521986001 | 0.840 ppm |
| 2020-09-22 | 527324001 | 0.707 ppm |
| 2020-09-22 | 527324001 | 1.08 ppm |
| 2020-10-22 | 532821001 | 0.619 ppm |
| 2020-10-22 | 532821001 | 0.760 ppm |
| 2020-11-16 | 536555001 | 0.745 ppm |
| 2020-11-16 | 536555001 | 0.930 ppm |
| 2020-12-15 | 540746001 | 0.790 ppm |
| 2020-12-15 | 540746001 | 1.12 ppm |
| 2021-01-25 | 544987001 | 0.668 ppm |
| 2021-01-25 | 544987001 | 0.800 ppm |
| 2021-02-10 | 547271001 | 0.722 ppm |
| 2021-02-10 | 547271001 | 0.940 ppm |
| 2021-02-10 | 547271001 | 0.722 ppm |
| 2021-02-10 | 547271001 | 0.940 ppm |
| 2021-03-16 | 552293001 | 0.736 ppm |
| 2021-03-16 | 552293001 | 0.960 ppm |
| 2021-03-16 | 552293001 | 0.736 ppm |
| 2021-03-16 | 552293001 | 0.960 ppm |
| 2021-04-20 | 557666001 | 0.707 ppm |
| 2021-04-20 | 557666001 | 0.880 ppm |
| 2021-05-25 | 563808001 | 0.811 ppm |
| 2021-05-25 | 563808001 | 1.08 ppm |
| 2021-06-16 | 21F0629-01 | 0.120 ppm |
| 2021-06-21 | 568280001 | 0.689 ppm |
| 2021-06-21 | 568280001 | 0.870 ppm |
| 2021-07-07 | 571039001 | 0.665 ppm |
| 2021-07-07 | 571039001 | 0.870 ppm |
| 2021-08-23 | 579842001 | 0.662 ppm |
| 2021-08-23 | 579842001 | 0.760 ppm |
| 2021-09-27 | 586414001 | 0.672 ppm |
| 2021-09-27 | 586414001 | 0.950 ppm |
| 2021-10-25 | 591506001 | 0.680 ppm |
| 2021-10-25 | 591506001 | 0.980 ppm |
| 2021-11-22 | 595793001 | 0.703 ppm |
| 2021-11-22 | 595793001 | 0.730 ppm |
| 2021-12-27 | 599967001 | 0.673 ppm |
| 2021-12-27 | 599967001 | 0.880 ppm |
| 2022-01-24 | 603121001 | 0.634 ppm |
| 2022-01-24 | 603121001 | 0.660 ppm |
| 2022-02-07 | 604915001 | 0.504 ppm |
| 2022-02-07 | 604915001 | 0.720 ppm |
| 2022-03-02 | 607921001 | 0.517 ppm |
| 2022-03-02 | 607921001 | 0.700 ppm |
| 2022-04-13 | 614120001 | 0.639 ppm |
| 2022-04-13 | 614120001 | 0.800 ppm |
| 2022-05-23 | 621271001 | 0.702 ppm |
| 2022-05-23 | 621271001 | 0.760 ppm |
| 2022-06-27 | 627445001 | 0.670 ppm |
| 2022-06-27 | 627445001 | 0.810 ppm |
| 2022-07-25 | 633140001 | 0.667 ppm |
| 2022-07-25 | 633140001 | 0.830 ppm |
| 2022-08-03 | 635046001 | 0.656 ppm |
| 2022-08-03 | 635046001 | 0.670 ppm |
| 2022-09-21 | 644252001 | 0.688 ppm |
| 2022-09-21 | 644252001 | 0.700 ppm |
| 2022-10-18 | 649336001 | 0.698 ppm |
| 2022-10-18 | 649336001 | 0.750 ppm |
| 2022-11-21 | 654357001 | 0.667 ppm |
| 2022-11-21 | 654357001 | 0.830 ppm |
| 2022-12-19 | 657994001 | 0.626 ppm |
| 2022-12-19 | 657994001 | 0.780 ppm |
| 2023-01-24 | 662060001 | 0.584 ppm |
| 2023-01-24 | 662060001 | 0.840 ppm |
| 2023-02-14 | 664784001 | 0.456 ppm |
| 2023-02-14 | 664784001 | 0.620 ppm |
| 2023-03-21 | 669588001 | 0.612 ppm |
| 2023-03-21 | 669588001 | 0.800 ppm |
| 2023-04-17 | 673613001 | 0.317 ppm |
| 2023-04-17 | 673613001 | 0.620 ppm |
| 2023-05-25 | 680775001 | 0.651 ppm |
| 2023-05-25 | 680775001 | 0.760 ppm |
| 2023-06-07 | 682680001 | 0.181 ppm |
| 2023-06-07 | 682680001 | 0.620 ppm |
| 2023-06-12 | 23F0340-01 | 0.110 ppm |
| 2023-06-12 | 23F0340-02 | 0.140 ppm |
| 2023-07-17 | 689402001 | 0.464 ppm |
| 2023-07-17 | 689402001 | 0.780 ppm |
| 2023-08-14 | 694896001 | 0.476 ppm |
| 2023-08-14 | 694896001 | 0.600 ppm |
| 2023-09-19 | 701459001 | 0.459 ppm |
| 2023-09-19 | 701459001 | 0.780 ppm |
| 2023-10-23 | 707697001 | 0.499 ppm |
| 2023-10-23 | 707697001 | 0.680 ppm |
| 2023-11-15 | 711260001 | 0.549 ppm |
| 2023-11-15 | 711260001 | 0.580 ppm |
| 2023-12-18 | 715312001 | 0.607 ppm |
| 2023-12-18 | 715312001 | 0.610 ppm |