Fluoride
Superior Water Light & Power Company
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.
Testing results - average by year
Year | Average result | Samples taken | Detections | Range of results |
---|---|---|---|---|
2014 | 0.726 ppm | 25 | 25 | 0.635 ppm - 0.860 ppm |
2015 | 0.732 ppm | 25 | 25 | 0.586 ppm - 0.810 ppm |
2016 | 0.670 ppm | 25 | 25 | 0.600 ppm - 0.810 ppm |
2017 | 0.684 ppm | 25 | 25 | 0.485 ppm - 0.950 ppm |
2018 | 0.737 ppm | 25 | 25 | 0.597 ppm - 0.920 ppm |
2019 | 0.706 ppm | 25 | 25 | 0.620 ppm - 0.889 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 |
---|---|---|
2014-01-22 | 117544001 | 0.831 ppm |
2014-01-22 | 117544001 | 0.850 ppm |
2014-02-18 | 120487001 | 0.714 ppm |
2014-02-18 | 120487001 | 0.760 ppm |
2014-03-17 | 124278001 | 0.780 ppm |
2014-03-17 | 124278001 | 0.804 ppm |
2014-04-23 | 782244 | 0.640 ppm |
2014-04-24 | 129337001 | 0.635 ppm |
2014-04-24 | 129337001 | 0.700 ppm |
2014-05-19 | 134453001 | 0.667 ppm |
2014-05-19 | 134453001 | 0.750 ppm |
2014-06-16 | 140260001 | 0.810 ppm |
2014-06-16 | 140260001 | 0.860 ppm |
2014-07-28 | 148498001 | 0.670 ppm |
2014-07-28 | 148498001 | 0.683 ppm |
2014-08-26 | 154175001 | 0.697 ppm |
2014-08-26 | 154175001 | 0.750 ppm |
2014-09-16 | 158595001 | 0.670 ppm |
2014-09-16 | 158595001 | 0.680 ppm |
2014-10-16 | 164301001 | 0.700 ppm |
2014-10-16 | 164301001 | 0.708 ppm |
2014-11-18 | 169620001 | 0.686 ppm |
2014-11-18 | 169620001 | 0.710 ppm |
2014-12-09 | 172503001 | 0.690 ppm |
2014-12-09 | 172503001 | 0.700 ppm |
2015-01-13 | 176053001 | 0.737 ppm |
2015-01-13 | 176053001 | 0.790 ppm |
2015-02-09 | 842349 | 0.750 ppm |
2015-02-09 | 179627001 | 0.757 ppm |
2015-02-09 | 179627001 | 0.790 ppm |
2015-03-10 | 183423001 | 0.725 ppm |
2015-03-10 | 183423001 | 0.780 ppm |
2015-04-13 | 188347001 | 0.719 ppm |
2015-04-13 | 188347001 | 0.780 ppm |
2015-05-26 | 196292001 | 0.630 ppm |
2015-05-26 | 196292001 | 0.682 ppm |
2015-06-16 | 200843001 | 0.690 ppm |
2015-06-16 | 200843001 | 0.802 ppm |
2015-07-15 | 206377001 | 0.750 ppm |
2015-07-15 | 206377001 | 0.810 ppm |
2015-08-11 | 211858001 | 0.716 ppm |
2015-08-11 | 211858001 | 0.780 ppm |
2015-09-15 | 218442001 | 0.715 ppm |
2015-09-15 | 218442001 | 0.720 ppm |
2015-10-15 | 224205001 | 0.695 ppm |
2015-10-15 | 224205001 | 0.750 ppm |
2015-11-10 | 228490001 | 0.687 ppm |
2015-11-10 | 228490001 | 0.790 ppm |
2015-12-08 | 232368001 | 0.586 ppm |
2015-12-08 | 232368001 | 0.680 ppm |
2016-01-25 | 237416001 | 0.642 ppm |
2016-01-25 | 237416001 | 0.670 ppm |
2016-02-16 | 905546 | 0.730 ppm |
2016-02-18 | 240511001 | 0.721 ppm |
2016-02-18 | 240511001 | 0.810 ppm |
2016-03-14 | 244734001 | 0.676 ppm |
2016-03-14 | 244734001 | 0.690 ppm |
2016-04-13 | 248943001 | 0.649 ppm |
2016-04-13 | 248943001 | 0.680 ppm |
2016-05-17 | 255776001 | 0.664 ppm |
2016-05-17 | 255776001 | 0.680 ppm |
2016-06-21 | 262521001 | 0.655 ppm |
2016-06-21 | 262521001 | 0.680 ppm |
2016-07-13 | 266424001 | 0.610 ppm |
2016-07-13 | 266424001 | 0.617 ppm |
2016-08-15 | 272834001 | 0.640 ppm |
2016-08-15 | 272834001 | 0.686 ppm |
2016-09-13 | 278036001 | 0.685 ppm |
2016-09-13 | 278036001 | 0.690 ppm |
2016-10-25 | 286290001 | 0.668 ppm |
2016-10-25 | 286290001 | 0.680 ppm |
2016-11-08 | 288656001 | 0.600 ppm |
2016-11-08 | 288656001 | 0.691 ppm |
2016-12-14 | 293587001 | 0.610 ppm |
2016-12-14 | 293587001 | 0.629 ppm |
2017-01-23 | 297727001 | 0.629 ppm |
2017-01-23 | 297727001 | 0.690 ppm |
2017-02-21 | 301459001 | 0.586 ppm |
2017-02-21 | 301459001 | 0.590 ppm |
2017-03-21 | 306049001 | 0.558 ppm |
2017-03-21 | 306049001 | 0.590 ppm |
2017-04-11 | 309866001 | 0.485 ppm |
2017-04-11 | 309866001 | 0.540 ppm |
2017-04-25 | 985192 | 0.560 ppm |
2017-05-23 | 318342001 | 0.538 ppm |
2017-05-23 | 318342001 | 0.550 ppm |
2017-06-06 | 320687001 | 0.770 ppm |
2017-06-06 | 320687001 | 0.783 ppm |
2017-07-19 | 330333001 | 0.730 ppm |
2017-07-19 | 330333001 | 0.742 ppm |
2017-08-21 | 338218001 | 0.758 ppm |
2017-08-21 | 338218001 | 0.780 ppm |
2017-09-20 | 344317001 | 0.720 ppm |
2017-09-20 | 344317001 | 0.763 ppm |
2017-10-19 | 350164001 | 0.710 ppm |
2017-10-19 | 350164001 | 0.760 ppm |
2017-11-01 | 352290001 | 0.727 ppm |
2017-11-01 | 352290001 | 0.740 ppm |
2017-12-11 | 359495001 | 0.850 ppm |
2017-12-11 | 359495001 | 0.950 ppm |
2018-01-10 | 362609001 | 0.648 ppm |
2018-01-10 | 362609001 | 0.790 ppm |
2018-02-21 | 369135001 | 0.648 ppm |
2018-02-21 | 369135001 | 0.670 ppm |
2018-02-21 | 1042018 | 0.680 ppm |
2018-03-20 | 372599001 | 0.631 ppm |
2018-03-20 | 372599001 | 0.640 ppm |
2018-04-04 | 374866001 | 0.597 ppm |
2018-04-04 | 374866001 | 0.670 ppm |
2018-05-08 | 381468001 | 0.700 ppm |
2018-05-08 | 381468001 | 0.777 ppm |
2018-06-11 | 388538001 | 0.676 ppm |
2018-06-11 | 388538001 | 0.680 ppm |
2018-07-18 | 395865001 | 0.770 ppm |
2018-07-18 | 395865001 | 0.772 ppm |
2018-08-02 | 398543001 | 0.760 ppm |
2018-08-02 | 398543001 | 0.817 ppm |
2018-09-12 | 407803001 | 0.660 ppm |
2018-09-12 | 407803001 | 0.776 ppm |
2018-10-08 | 413920001 | 0.903 ppm |
2018-10-08 | 413920001 | 0.920 ppm |
2018-11-20 | 420924001 | 0.800 ppm |
2018-11-20 | 420924001 | 0.860 ppm |
2018-12-10 | 424233001 | 0.752 ppm |
2018-12-10 | 424233001 | 0.840 ppm |
2019-01-23 | 1102680 | 0.690 ppm |
2019-01-25 | 429446001 | 0.660 ppm |
2019-01-25 | 429446001 | 0.703 ppm |
2019-02-27 | 434054001 | 0.650 ppm |
2019-02-27 | 434054001 | 0.813 ppm |
2019-03-18 | 436772001 | 0.720 ppm |
2019-03-18 | 436772001 | 0.795 ppm |
2019-04-25 | 442588001 | 0.620 ppm |
2019-04-25 | 442588001 | 0.712 ppm |
2019-05-14 | 446669001 | 0.620 ppm |
2019-05-14 | 446669001 | 0.715 ppm |
2019-06-03 | 450212001 | 0.641 ppm |
2019-06-03 | 450212001 | 0.720 ppm |
2019-07-08 | 457015001 | 0.800 ppm |
2019-07-08 | 457015001 | 0.889 ppm |
2019-08-13 | 464192001 | 0.679 ppm |
2019-08-13 | 464192001 | 0.720 ppm |
2019-09-17 | 471543001 | 0.638 ppm |
2019-09-17 | 471543001 | 0.670 ppm |
2019-10-14 | 476944001 | 0.660 ppm |
2019-10-14 | 476944001 | 0.698 ppm |
2019-11-25 | 483489001 | 0.653 ppm |
2019-11-25 | 483489001 | 0.770 ppm |
2019-12-11 | 486016001 | 0.680 ppm |
2019-12-11 | 486016001 | 0.742 ppm |