Fluoride
Neillsville 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 | 0.740 ppm | 24 | 24 | 0.657 ppm - 0.800 ppm |
| 2019 | 0.692 ppm | 24 | 24 | 0.491 ppm - 0.794 ppm |
| 2020 | 0.746 ppm | 21 | 21 | 0.640 ppm - 1.02 ppm |
| 2021 | 0.720 ppm | 28 | 28 | 0.567 ppm - 0.875 ppm |
| 2022 | 0.792 ppm | 24 | 24 | 0.648 ppm - 0.914 ppm |
| 2023 | 0.710 ppm | 25 | 25 | 0.490 ppm - 0.870 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 |
|---|---|---|
| 2018-01-23 | 364163001 | 0.758 ppm |
| 2018-01-23 | 364163001 | 0.800 ppm |
| 2018-02-12 | 366986001 | 0.728 ppm |
| 2018-02-12 | 366986001 | 0.800 ppm |
| 2018-03-05 | 369676001 | 0.787 ppm |
| 2018-03-05 | 369676001 | 0.800 ppm |
| 2018-04-11 | 376107001 | 0.740 ppm |
| 2018-04-11 | 376107001 | 0.756 ppm |
| 2018-05-16 | 383027001 | 0.750 ppm |
| 2018-05-16 | 383027001 | 0.800 ppm |
| 2018-06-12 | 388365001 | 0.678 ppm |
| 2018-06-12 | 388365001 | 0.750 ppm |
| 2018-07-16 | 394917001 | 0.690 ppm |
| 2018-07-16 | 394917001 | 0.760 ppm |
| 2018-08-14 | 401236001 | 0.682 ppm |
| 2018-08-14 | 401236001 | 0.740 ppm |
| 2018-09-04 | 405279001 | 0.687 ppm |
| 2018-09-04 | 405279001 | 0.710 ppm |
| 2018-10-15 | 414662001 | 0.700 ppm |
| 2018-10-15 | 414662001 | 0.744 ppm |
| 2018-11-06 | 418582001 | 0.750 ppm |
| 2018-11-06 | 418582001 | 0.790 ppm |
| 2018-12-10 | 423688001 | 0.657 ppm |
| 2018-12-10 | 423688001 | 0.706 ppm |
| 2019-01-08 | 427065001 | 0.660 ppm |
| 2019-01-08 | 427065001 | 0.689 ppm |
| 2019-02-13 | 431450001 | 0.590 ppm |
| 2019-02-13 | 431450001 | 0.649 ppm |
| 2019-03-05 | 434111001 | 0.700 ppm |
| 2019-03-05 | 434111001 | 0.738 ppm |
| 2019-04-08 | 439428001 | 0.640 ppm |
| 2019-04-08 | 439428001 | 0.688 ppm |
| 2019-05-14 | 446252001 | 0.660 ppm |
| 2019-05-14 | 446252001 | 0.755 ppm |
| 2019-06-04 | 449996001 | 0.750 ppm |
| 2019-06-04 | 449996001 | 0.752 ppm |
| 2019-07-15 | 457801001 | 0.710 ppm |
| 2019-07-15 | 457801001 | 0.785 ppm |
| 2019-08-06 | 462191001 | 0.710 ppm |
| 2019-08-06 | 462191001 | 0.778 ppm |
| 2019-09-09 | 468849001 | 0.660 ppm |
| 2019-09-09 | 468849001 | 0.766 ppm |
| 2019-10-15 | 476696001 | 0.707 ppm |
| 2019-10-15 | 476696001 | 0.750 ppm |
| 2019-11-05 | 480128001 | 0.676 ppm |
| 2019-11-05 | 480128001 | 0.794 ppm |
| 2019-12-03 | 484342001 | 0.491 ppm |
| 2019-12-03 | 484342001 | 0.500 ppm |
| 2020-01-14 | 489613001 | 0.650 ppm |
| 2020-01-14 | 489613001 | 0.732 ppm |
| 2020-04-06 | 499782001 | 0.729 ppm |
| 2020-04-06 | 499782001 | 0.755 ppm |
| 2020-05-12 | 504614001 | 0.640 ppm |
| 2020-05-12 | 504614001 | 0.704 ppm |
| 2020-06-09 | 509012001 | 0.700 ppm |
| 2020-06-09 | 509012001 | 0.730 ppm |
| 2020-07-20 | 515751001 | 0.690 ppm |
| 2020-07-20 | 515751001 | 0.725 ppm |
| 2020-07-29 | 20G0971-01 | 1.02 ppm |
| 2020-08-05 | 518651001 | 0.686 ppm |
| 2020-08-05 | 518651001 | 0.733 ppm |
| 2020-09-15 | 525901001 | 0.745 ppm |
| 2020-09-15 | 525901001 | 0.776 ppm |
| 2020-10-14 | 531455001 | 0.765 ppm |
| 2020-10-14 | 531455001 | 0.790 ppm |
| 2020-11-19 | 537210001 | 0.764 ppm |
| 2020-11-19 | 537210001 | 0.793 ppm |
| 2020-12-07 | 539639001 | 0.736 ppm |
| 2020-12-07 | 539639001 | 0.807 ppm |
| 2021-01-13 | 543855001 | 0.727 ppm |
| 2021-01-13 | 543855001 | 0.814 ppm |
| 2021-02-10 | 547339001 | 0.639 ppm |
| 2021-02-10 | 547339001 | 0.740 ppm |
| 2021-02-10 | 547339001 | 0.639 ppm |
| 2021-02-10 | 547339001 | 0.740 ppm |
| 2021-03-10 | 551422001 | 0.624 ppm |
| 2021-03-10 | 551422001 | 0.779 ppm |
| 2021-03-10 | 551422001 | 0.624 ppm |
| 2021-03-10 | 551422001 | 0.779 ppm |
| 2021-04-06 | 555004001 | 0.615 ppm |
| 2021-04-06 | 555004001 | 0.803 ppm |
| 2021-05-12 | 561634001 | 0.691 ppm |
| 2021-05-12 | 561634001 | 0.812 ppm |
| 2021-06-15 | 567533001 | 0.729 ppm |
| 2021-06-15 | 567533001 | 0.786 ppm |
| 2021-07-26 | 574673001 | 0.598 ppm |
| 2021-07-26 | 574673001 | 0.680 ppm |
| 2021-08-10 | 577590001 | 0.845 ppm |
| 2021-08-10 | 577590001 | 0.875 ppm |
| 2021-09-13 | 583732001 | 0.725 ppm |
| 2021-09-13 | 583732001 | 0.787 ppm |
| 2021-10-18 | 590328001 | 0.698 ppm |
| 2021-10-18 | 590328001 | 0.787 ppm |
| 2021-11-16 | 595180001 | 0.567 ppm |
| 2021-11-16 | 595180001 | 0.623 ppm |
| 2021-12-14 | 598907001 | 0.653 ppm |
| 2021-12-14 | 598907001 | 0.772 ppm |
| 2022-01-11 | 601797001 | 0.788 ppm |
| 2022-01-11 | 601797001 | 0.811 ppm |
| 2022-02-08 | 605236001 | 0.781 ppm |
| 2022-02-08 | 605236001 | 0.832 ppm |
| 2022-03-02 | 607958001 | 0.751 ppm |
| 2022-03-02 | 607958001 | 0.844 ppm |
| 2022-04-06 | 612938001 | 0.727 ppm |
| 2022-04-06 | 612938001 | 0.843 ppm |
| 2022-05-17 | 620437001 | 0.680 ppm |
| 2022-05-17 | 620437001 | 0.785 ppm |
| 2022-06-15 | 625654001 | 0.709 ppm |
| 2022-06-15 | 625654001 | 0.869 ppm |
| 2022-07-20 | 632424001 | 0.751 ppm |
| 2022-07-20 | 632424001 | 0.914 ppm |
| 2022-08-17 | 637837001 | 0.648 ppm |
| 2022-08-17 | 637837001 | 0.813 ppm |
| 2022-09-20 | 644001001 | 0.745 ppm |
| 2022-09-20 | 644001001 | 0.893 ppm |
| 2022-10-03 | 646489001 | 0.770 ppm |
| 2022-10-03 | 646489001 | 0.907 ppm |
| 2022-11-07 | 652581001 | 0.767 ppm |
| 2022-11-07 | 652581001 | 0.800 ppm |
| 2022-12-13 | 657418001 | 0.753 ppm |
| 2022-12-13 | 657418001 | 0.820 ppm |
| 2023-01-17 | 661261001 | 0.735 ppm |
| 2023-01-17 | 661261001 | 0.850 ppm |
| 2023-02-15 | 665032001 | 0.731 ppm |
| 2023-02-15 | 665032001 | 0.820 ppm |
| 2023-03-08 | 23C0293-01 | 0.490 ppm |
| 2023-03-27 | 670318001 | 0.653 ppm |
| 2023-03-27 | 670318001 | 0.790 ppm |
| 2023-04-24 | 675378001 | 0.790 ppm |
| 2023-04-24 | 675378001 | 0.870 ppm |
| 2023-05-10 | 678371001 | 0.508 ppm |
| 2023-05-10 | 678371001 | 0.590 ppm |
| 2023-06-21 | 685745001 | 0.610 ppm |
| 2023-06-21 | 685745001 | 0.750 ppm |
| 2023-07-17 | 689978001 | 0.736 ppm |
| 2023-07-17 | 689978001 | 0.790 ppm |
| 2023-08-07 | 694453001 | 0.794 ppm |
| 2023-08-07 | 694453001 | 0.830 ppm |
| 2023-09-26 | 703001001 | 0.598 ppm |
| 2023-09-26 | 703001001 | 0.710 ppm |
| 2023-10-04 | 704733001 | 0.625 ppm |
| 2023-10-04 | 704733001 | 0.770 ppm |
| 2023-11-07 | 710099001 | 0.641 ppm |
| 2023-11-07 | 710099001 | 0.720 ppm |
| 2023-12-04 | 713890001 | 0.604 ppm |
| 2023-12-04 | 713890001 | 0.750 ppm |