Fluoride
Juneau 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 | 1.11 ppm | 27 | 27 | 0.270 ppm - 2.71 ppm |
| 2015 | 1.10 ppm | 26 | 26 | 0.885 ppm - 1.54 ppm |
| 2016 | 0.957 ppm | 26 | 26 | 0.110 ppm - 1.20 ppm |
| 2017 | 0.824 ppm | 27 | 27 | 0.480 ppm - 1.20 ppm |
| 2018 | 0.700 ppm | 24 | 24 | 0.325 ppm - 0.890 ppm |
| 2019 | 0.796 ppm | 24 | 24 | 0.660 ppm - 1.05 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 |
|---|---|---|
| 2014-01-07 | 115216001 | 1.24 ppm |
| 2014-01-07 | 115216001 | 1.41 ppm |
| 2014-02-04 | 118509001 | 0.987 ppm |
| 2014-02-04 | 118509001 | 1.25 ppm |
| 2014-03-04 | 121934001 | 0.642 ppm |
| 2014-03-04 | 121934001 | 0.790 ppm |
| 2014-04-01 | 125662001 | 1.07 ppm |
| 2014-04-01 | 125662001 | 1.25 ppm |
| 2014-05-06 | 131134001 | 0.748 ppm |
| 2014-05-06 | 131134001 | 0.840 ppm |
| 2014-06-03 | 136803001 | 0.911 ppm |
| 2014-06-03 | 136803001 | 1.01 ppm |
| 2014-07-01 | 142731001 | 0.670 ppm |
| 2014-07-01 | 142731001 | 0.750 ppm |
| 2014-07-16 | 803697 | 0.270 ppm |
| 2014-07-16 | 803696 | 0.290 ppm |
| 2014-07-16 | 803695 | 0.330 ppm |
| 2014-08-05 | 149735001 | 1.20 ppm |
| 2014-08-05 | 149735001 | 1.32 ppm |
| 2014-09-02 | 154656001 | 1.94 ppm |
| 2014-09-02 | 154656001 | 2.71 ppm |
| 2014-10-07 | 162469001 | 1.05 ppm |
| 2014-10-07 | 162469001 | 1.06 ppm |
| 2014-11-05 | 167410001 | 1.08 ppm |
| 2014-11-05 | 167410001 | 1.08 ppm |
| 2014-12-02 | 170996001 | 1.91 ppm |
| 2014-12-02 | 170996001 | 2.05 ppm |
| 2015-01-06 | 174725001 | 1.41 ppm |
| 2015-01-06 | 174725001 | 1.54 ppm |
| 2015-02-03 | 178321001 | 0.969 ppm |
| 2015-02-03 | 178321001 | 1.16 ppm |
| 2015-03-03 | 181872001 | 1.02 ppm |
| 2015-03-03 | 181872001 | 1.08 ppm |
| 2015-04-07 | 186894001 | 0.963 ppm |
| 2015-04-07 | 186894001 | 1.23 ppm |
| 2015-05-05 | 191729001 | 0.885 ppm |
| 2015-05-05 | 191729001 | 1.02 ppm |
| 2015-05-19 | 194850001 | 1.06 ppm |
| 2015-05-19 | 194850001 | 1.14 ppm |
| 2015-06-03 | 197709001 | 0.956 ppm |
| 2015-06-03 | 197709001 | 1.11 ppm |
| 2015-07-07 | 204252001 | 1.06 ppm |
| 2015-07-07 | 204252001 | 1.25 ppm |
| 2015-08-04 | 209935001 | 0.973 ppm |
| 2015-08-04 | 209935001 | 1.06 ppm |
| 2015-09-02 | 215424001 | 1.01 ppm |
| 2015-09-02 | 215424001 | 1.17 ppm |
| 2015-10-06 | 222498001 | 1.01 ppm |
| 2015-10-06 | 222498001 | 1.12 ppm |
| 2015-11-03 | 227169001 | 1.000 ppm |
| 2015-11-03 | 227169001 | 1.36 ppm |
| 2015-12-01 | 230785001 | 1.04 ppm |
| 2015-12-01 | 230785001 | 1.04 ppm |
| 2016-01-05 | 234748001 | 0.855 ppm |
| 2016-01-05 | 234748001 | 0.930 ppm |
| 2016-02-02 | 238207001 | 0.110 ppm |
| 2016-02-02 | 238207001 | 1.01 ppm |
| 2016-03-01 | 241879001 | 0.890 ppm |
| 2016-03-01 | 241879001 | 0.955 ppm |
| 2016-04-05 | 247313001 | 1.02 ppm |
| 2016-04-05 | 247313001 | 1.07 ppm |
| 2016-05-03 | 252420001 | 0.919 ppm |
| 2016-05-03 | 252420001 | 1.05 ppm |
| 2016-06-07 | 259050001 | 1.11 ppm |
| 2016-06-07 | 259050001 | 1.20 ppm |
| 2016-07-05 | 264238001 | 0.996 ppm |
| 2016-07-05 | 264238001 | 1.04 ppm |
| 2016-08-02 | 270078001 | 1.06 ppm |
| 2016-08-02 | 270078001 | 1.13 ppm |
| 2016-09-06 | 275789001 | 0.850 ppm |
| 2016-09-06 | 275789001 | 0.953 ppm |
| 2016-10-04 | 282543001 | 0.890 ppm |
| 2016-10-04 | 282543001 | 1.12 ppm |
| 2016-10-11 | 283555001 | 1.14 ppm |
| 2016-10-11 | 283555001 | 1.14 ppm |
| 2016-11-01 | 286945001 | 0.956 ppm |
| 2016-11-01 | 286945001 | 1.11 ppm |
| 2016-12-06 | 291828001 | 0.640 ppm |
| 2016-12-06 | 291828001 | 0.750 ppm |
| 2017-01-03 | 294888001 | 0.646 ppm |
| 2017-01-03 | 294888001 | 0.680 ppm |
| 2017-02-07 | 299233001 | 0.824 ppm |
| 2017-02-07 | 299233001 | 0.890 ppm |
| 2017-03-07 | 303176001 | 0.764 ppm |
| 2017-03-07 | 303176001 | 0.850 ppm |
| 2017-04-04 | 307974001 | 0.795 ppm |
| 2017-04-04 | 307974001 | 1.000 ppm |
| 2017-05-02 | 313431001 | 0.750 ppm |
| 2017-05-02 | 313431001 | 0.940 ppm |
| 2017-06-07 | 320526001 | 0.660 ppm |
| 2017-06-07 | 320526001 | 0.840 ppm |
| 2017-07-11 | 327887001 | 0.820 ppm |
| 2017-07-11 | 327887001 | 0.888 ppm |
| 2017-08-01 | 332674001 | 0.887 ppm |
| 2017-08-01 | 332674001 | 1.09 ppm |
| 2017-09-06 | 340471001 | 0.898 ppm |
| 2017-09-06 | 340471001 | 0.900 ppm |
| 2017-09-27 | 1021357 | 0.480 ppm |
| 2017-09-27 | 1021348 | 0.670 ppm |
| 2017-09-27 | 1021353 | 1.20 ppm |
| 2017-10-11 | 348543001 | 0.815 ppm |
| 2017-10-11 | 348543001 | 0.840 ppm |
| 2017-11-07 | 353253001 | 0.769 ppm |
| 2017-11-07 | 353253001 | 0.950 ppm |
| 2017-12-13 | 359353001 | 0.678 ppm |
| 2017-12-13 | 359353001 | 0.720 ppm |
| 2018-01-23 | 364122001 | 0.325 ppm |
| 2018-01-23 | 364122001 | 0.730 ppm |
| 2018-02-06 | 365890001 | 0.677 ppm |
| 2018-02-06 | 365890001 | 0.780 ppm |
| 2018-03-14 | 371413001 | 0.580 ppm |
| 2018-03-14 | 371413001 | 0.700 ppm |
| 2018-04-03 | 374467001 | 0.590 ppm |
| 2018-04-03 | 374467001 | 0.629 ppm |
| 2018-05-01 | 379414001 | 0.698 ppm |
| 2018-05-01 | 379414001 | 0.830 ppm |
| 2018-06-05 | 386676001 | 0.727 ppm |
| 2018-06-05 | 386676001 | 0.890 ppm |
| 2018-07-10 | 393595001 | 0.687 ppm |
| 2018-07-10 | 393595001 | 0.760 ppm |
| 2018-08-14 | 401248001 | 0.709 ppm |
| 2018-08-14 | 401248001 | 0.770 ppm |
| 2018-09-04 | 405112001 | 0.560 ppm |
| 2018-09-04 | 405112001 | 0.594 ppm |
| 2018-10-03 | 412508001 | 0.688 ppm |
| 2018-10-03 | 412508001 | 0.810 ppm |
| 2018-11-06 | 418565001 | 0.747 ppm |
| 2018-11-06 | 418565001 | 0.880 ppm |
| 2018-12-18 | 425161001 | 0.710 ppm |
| 2018-12-18 | 425161001 | 0.717 ppm |
| 2019-01-22 | 428800001 | 0.825 ppm |
| 2019-01-22 | 428800001 | 0.960 ppm |
| 2019-02-05 | 430422001 | 0.700 ppm |
| 2019-02-05 | 430422001 | 0.890 ppm |
| 2019-03-05 | 434070001 | 0.823 ppm |
| 2019-03-05 | 434070001 | 0.960 ppm |
| 2019-04-03 | 438749001 | 0.750 ppm |
| 2019-04-03 | 438749001 | 0.755 ppm |
| 2019-05-07 | 444780001 | 0.670 ppm |
| 2019-05-07 | 444780001 | 0.717 ppm |
| 2019-06-04 | 449998001 | 0.730 ppm |
| 2019-06-04 | 449998001 | 0.890 ppm |
| 2019-07-09 | 456706001 | 0.765 ppm |
| 2019-07-09 | 456706001 | 1.05 ppm |
| 2019-08-06 | 462202001 | 0.774 ppm |
| 2019-08-06 | 462202001 | 0.800 ppm |
| 2019-09-03 | 467549001 | 0.660 ppm |
| 2019-09-03 | 467549001 | 0.783 ppm |
| 2019-10-01 | 473955001 | 0.754 ppm |
| 2019-10-01 | 473955001 | 0.870 ppm |
| 2019-11-05 | 480010001 | 0.762 ppm |
| 2019-11-05 | 480010001 | 0.870 ppm |
| 2019-12-02 | 483920001 | 0.670 ppm |
| 2019-12-02 | 483920001 | 0.686 ppm |