Fluoride
Appleton Waterworks
Fluoride occurs naturally in surface and groundwater and is also added to drinking water by many water systems. Read More.
Fluoride has been promoted as a chemical that reduces dental cavities. Yet it is now well-established that fluoride primarily exerts its protective effects through topical mechanisms, such as sodium fluoride in toothpaste and mouthwash. In contrast, long-term ingestion of fluoride in water increases dental fluorosis, which includes mottling, pitting and weakening of the teeth. 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 fractures, although these effects may occur at lower doses.
Even fluoride levels of 0.7 ppm, the amount of fluoride in drinking water recommended by the U.S. Public Health Service, can result in too much fluoride for bottle-fed babies. EWG recommends that caregivers mix baby formula with fluoride-free water. The National Toxicology Program is investigating the potential for low doses of fluoride to alter thyroid function and childhood brain development.
Samples
Samples exceeding legal limit (MCL)
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2014 | 0.719 ppm | 25 | 25 | 0.430 ppm - 0.860 ppm |
| 2015 | 0.694 ppm | 25 | 25 | 0.394 ppm - 0.850 ppm |
| 2016 | 0.698 ppm | 25 | 25 | 0.630 ppm - 0.780 ppm |
| 2017 | 0.710 ppm | 25 | 25 | 0.623 ppm - 0.800 ppm |
| 2018 | 0.646 ppm | 25 | 25 | 0.568 ppm - 0.750 ppm |
| 2019 | 0.616 ppm | 25 | 25 | 0.468 ppm - 0.710 ppm |
ppm = parts per million
State and national drinking water standards and health guidelines
EPA Maximum Contaminant
Level (MCL) 4 ppm
ppm = parts per million
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2014-01-13 | 116259001 | 0.430 ppm |
| 2014-01-13 | 116259001 | 0.740 ppm |
| 2014-02-03 | 118430001 | 0.684 ppm |
| 2014-02-03 | 118430001 | 0.780 ppm |
| 2014-03-10 | 122923001 | 0.583 ppm |
| 2014-03-10 | 122923001 | 0.660 ppm |
| 2014-04-01 | 125930001 | 0.581 ppm |
| 2014-04-01 | 125930001 | 0.650 ppm |
| 2014-04-21 | 781795 | 0.760 ppm |
| 2014-05-05 | 131128001 | 0.780 ppm |
| 2014-05-05 | 131128001 | 0.810 ppm |
| 2014-06-02 | 136806001 | 0.723 ppm |
| 2014-06-02 | 136806001 | 0.750 ppm |
| 2014-07-07 | 144088001 | 0.747 ppm |
| 2014-07-07 | 144088001 | 0.790 ppm |
| 2014-08-04 | 149982001 | 0.653 ppm |
| 2014-08-04 | 149982001 | 0.670 ppm |
| 2014-09-02 | 154944001 | 0.584 ppm |
| 2014-09-02 | 154944001 | 0.630 ppm |
| 2014-10-07 | 162738001 | 0.840 ppm |
| 2014-10-07 | 162738001 | 0.860 ppm |
| 2014-11-10 | 168247001 | 0.828 ppm |
| 2014-11-10 | 168247001 | 0.830 ppm |
| 2014-12-01 | 170755001 | 0.781 ppm |
| 2014-12-01 | 170755001 | 0.830 ppm |
| 2015-01-05 | 174648001 | 0.781 ppm |
| 2015-01-05 | 174648001 | 0.840 ppm |
| 2015-02-03 | 178463001 | 0.637 ppm |
| 2015-02-03 | 841742 | 0.640 ppm |
| 2015-02-03 | 178463001 | 0.780 ppm |
| 2015-03-03 | 182153001 | 0.578 ppm |
| 2015-03-03 | 182153001 | 0.710 ppm |
| 2015-04-01 | 185883001 | 0.619 ppm |
| 2015-04-01 | 185883001 | 0.660 ppm |
| 2015-05-04 | 191755001 | 0.394 ppm |
| 2015-05-04 | 191755001 | 0.460 ppm |
| 2015-06-03 | 197851001 | 0.731 ppm |
| 2015-06-03 | 197851001 | 0.850 ppm |
| 2015-07-01 | 203715001 | 0.721 ppm |
| 2015-07-01 | 203715001 | 0.780 ppm |
| 2015-08-05 | 210340001 | 0.746 ppm |
| 2015-08-05 | 210340001 | 0.770 ppm |
| 2015-09-02 | 215565001 | 0.714 ppm |
| 2015-09-02 | 215565001 | 0.800 ppm |
| 2015-10-26 | 225922001 | 0.659 ppm |
| 2015-10-26 | 225922001 | 0.710 ppm |
| 2015-11-04 | 227376001 | 0.646 ppm |
| 2015-11-04 | 227376001 | 0.760 ppm |
| 2015-12-02 | 231046001 | 0.664 ppm |
| 2015-12-02 | 231046001 | 0.700 ppm |
| 2016-01-06 | 235010001 | 0.641 ppm |
| 2016-01-06 | 235010001 | 0.760 ppm |
| 2016-02-03 | 238393001 | 0.689 ppm |
| 2016-02-03 | 238393001 | 0.750 ppm |
| 2016-03-02 | 242186001 | 0.650 ppm |
| 2016-03-02 | 242186001 | 0.700 ppm |
| 2016-04-06 | 247595001 | 0.647 ppm |
| 2016-04-06 | 914084 | 0.690 ppm |
| 2016-04-06 | 247595001 | 0.760 ppm |
| 2016-05-04 | 252827001 | 0.630 ppm |
| 2016-05-04 | 252827001 | 0.670 ppm |
| 2016-06-01 | 257868001 | 0.636 ppm |
| 2016-06-01 | 257868001 | 0.670 ppm |
| 2016-07-06 | 264813001 | 0.714 ppm |
| 2016-07-06 | 264813001 | 0.770 ppm |
| 2016-08-03 | 270428001 | 0.679 ppm |
| 2016-08-03 | 270428001 | 0.760 ppm |
| 2016-09-07 | 276457001 | 0.677 ppm |
| 2016-09-07 | 276457001 | 0.710 ppm |
| 2016-10-06 | 282985001 | 0.631 ppm |
| 2016-10-06 | 282985001 | 0.690 ppm |
| 2016-11-08 | 288462001 | 0.694 ppm |
| 2016-11-08 | 288462001 | 0.780 ppm |
| 2016-12-07 | 292234001 | 0.698 ppm |
| 2016-12-07 | 292234001 | 0.760 ppm |
| 2017-01-11 | 296124001 | 0.672 ppm |
| 2017-01-11 | 296124001 | 0.750 ppm |
| 2017-02-07 | 299362001 | 0.716 ppm |
| 2017-02-07 | 299362001 | 0.800 ppm |
| 2017-03-02 | 302180001 | 0.623 ppm |
| 2017-03-02 | 302180001 | 0.720 ppm |
| 2017-04-10 | 309673001 | 0.675 ppm |
| 2017-04-10 | 309673001 | 0.720 ppm |
| 2017-05-04 | 314016001 | 0.720 ppm |
| 2017-05-04 | 314016001 | 0.720 ppm |
| 2017-05-22 | 992959 | 0.700 ppm |
| 2017-06-01 | 319782001 | 0.718 ppm |
| 2017-06-01 | 319782001 | 0.770 ppm |
| 2017-07-06 | 327276001 | 0.692 ppm |
| 2017-07-06 | 327276001 | 0.750 ppm |
| 2017-08-01 | 333146001 | 0.696 ppm |
| 2017-08-01 | 333146001 | 0.700 ppm |
| 2017-09-05 | 340486001 | 0.735 ppm |
| 2017-09-05 | 340486001 | 0.790 ppm |
| 2017-10-03 | 347154001 | 0.630 ppm |
| 2017-10-03 | 347154001 | 0.644 ppm |
| 2017-11-02 | 352297001 | 0.658 ppm |
| 2017-11-02 | 352297001 | 0.750 ppm |
| 2017-12-08 | 358891001 | 0.700 ppm |
| 2017-12-08 | 358891001 | 0.707 ppm |
| 2018-01-10 | 362573001 | 0.631 ppm |
| 2018-01-10 | 362573001 | 0.660 ppm |
| 2018-02-14 | 367282001 | 0.640 ppm |
| 2018-02-14 | 367282001 | 0.674 ppm |
| 2018-03-06 | 370130001 | 0.655 ppm |
| 2018-03-06 | 370130001 | 0.750 ppm |
| 2018-04-10 | 376101001 | 0.619 ppm |
| 2018-04-10 | 376101001 | 0.670 ppm |
| 2018-05-08 | 381302001 | 0.640 ppm |
| 2018-05-08 | 381302001 | 0.658 ppm |
| 2018-06-05 | 386979001 | 0.680 ppm |
| 2018-06-05 | 386979001 | 0.700 ppm |
| 2018-06-12 | 1060763 | 0.690 ppm |
| 2018-07-10 | 393922001 | 0.590 ppm |
| 2018-07-10 | 393922001 | 0.670 ppm |
| 2018-08-07 | 399879001 | 0.582 ppm |
| 2018-08-07 | 399879001 | 0.660 ppm |
| 2018-09-04 | 405511001 | 0.568 ppm |
| 2018-09-04 | 405511001 | 0.700 ppm |
| 2018-10-10 | 413990001 | 0.594 ppm |
| 2018-10-10 | 413990001 | 0.610 ppm |
| 2018-11-06 | 418775001 | 0.579 ppm |
| 2018-11-06 | 418775001 | 0.680 ppm |
| 2018-12-04 | 422855001 | 0.581 ppm |
| 2018-12-04 | 422855001 | 0.660 ppm |
| 2019-01-09 | 427333001 | 0.579 ppm |
| 2019-01-09 | 427333001 | 0.670 ppm |
| 2019-02-06 | 431140001 | 0.578 ppm |
| 2019-02-06 | 431140001 | 0.710 ppm |
| 2019-03-05 | 434356001 | 0.581 ppm |
| 2019-03-05 | 434356001 | 0.680 ppm |
| 2019-04-02 | 438697001 | 0.468 ppm |
| 2019-04-02 | 438697001 | 0.540 ppm |
| 2019-05-07 | 445123001 | 0.640 ppm |
| 2019-05-07 | 445123001 | 0.690 ppm |
| 2019-06-04 | 450104001 | 0.609 ppm |
| 2019-06-04 | 450104001 | 0.660 ppm |
| 2019-07-09 | 457026001 | 0.548 ppm |
| 2019-07-09 | 457026001 | 0.630 ppm |
| 2019-07-16 | 1135148 | 0.600 ppm |
| 2019-08-06 | 462585001 | 0.593 ppm |
| 2019-08-06 | 462585001 | 0.700 ppm |
| 2019-09-03 | 467866001 | 0.499 ppm |
| 2019-09-03 | 467866001 | 0.570 ppm |
| 2019-10-02 | 474463001 | 0.600 ppm |
| 2019-10-02 | 474463001 | 0.660 ppm |
| 2019-11-05 | 480540001 | 0.575 ppm |
| 2019-11-05 | 480540001 | 0.710 ppm |
| 2019-12-03 | 484578001 | 0.645 ppm |
| 2019-12-03 | 484578001 | 0.670 ppm |