Fluoride
Norman
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 |
|---|---|---|---|---|
| 2013 | N/A | 0 | 0 | N/A |
| 2014 | 0.339 ppm | 18 | 9 | ND - 1.09 ppm |
| 2015 | 0.241 ppm | 28 | 11 | ND - 0.748 ppm |
| 2016 | 0.531 ppm | 22 | 19 | ND - 0.939 ppm |
| 2017 | 0.384 ppm | 33 | 33 | 0.122 ppm - 0.885 ppm |
| 2018 | 0.619 ppm | 12 | 12 | 0.508 ppm - 0.781 ppm |
| 2019 | 0.480 ppm | 13 | 13 | 0.160 ppm - 0.630 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 |
|---|---|---|
| 2014-01-08 | 1268266 | 0.520 ppm |
| 2014-02-10 | 1276396 | ND |
| 2014-03-06 | 1283305 | 0.600 ppm |
| 2014-04-03 | 1290746 | 0.558 ppm |
| 2014-05-07 | 1299435 | ND |
| 2014-06-04 | 1313579 | 0.627 ppm |
| 2014-07-09 | 1316337 | 0.644 ppm |
| 2014-08-05 | 1323214 | 1.09 ppm |
| 2014-09-09 | 1333208 | 0.762 ppm |
| 2014-10-08 | 1341041 | 0.794 ppm |
| 2014-10-29 | 1346030 | ND |
| 2014-10-29 | 1346032 | ND |
| 2014-10-29 | 1346038 | ND |
| 2014-11-04 | 1348379 | ND |
| 2014-11-18 | 1351364 | ND |
| 2014-11-19 | 1351772 | ND |
| 2014-11-19 | 1351777 | ND |
| 2014-12-03 | 1355367 | 0.506 ppm |
| 2015-01-06 | 1362212 | 0.584 ppm |
| 2015-02-05 | 1370612 | 0.748 ppm |
| 2015-03-03 | 1376051 | 0.612 ppm |
| 2015-04-07 | 1384983 | 0.717 ppm |
| 2015-04-07 | 1384986 | 0.738 ppm |
| 2015-04-07 | 1384987 | ND |
| 2015-05-04 | 1392519 | ND |
| 2015-05-04 | 1392520 | ND |
| 2015-05-12 | 1394885 | 0.550 ppm |
| 2015-06-01 | 1399027 | ND |
| 2015-06-03 | 1400065 | ND |
| 2015-06-03 | 1400068 | ND |
| 2015-06-03 | 1400069 | ND |
| 2015-06-15 | 1402904 | ND |
| 2015-07-06 | 1407912 | ND |
| 2015-08-04 | 1416269 | 0.663 ppm |
| 2015-09-10 | 1426463 | 0.510 ppm |
| 2015-10-07 | 1433872 | 0.568 ppm |
| 2015-11-03 | 1441381 | ND |
| 2015-11-04 | 1441480 | ND |
| 2015-12-07 | 1449240 | 0.548 ppm |
| 2015-12-29 | 1454877 | ND |
| 2015-12-29 | 1454878 | ND |
| 2015-12-29 | 1454879 | ND |
| 2015-12-29 | 1454880 | ND |
| 2015-12-29 | 1454881 | ND |
| 2015-12-29 | 1454882 | 0.506 ppm |
| 2015-12-30 | 1454865 | ND |
| 2016-01-06 | 1456547 | 0.510 ppm |
| 2016-02-01 | 1463306 | 0.724 ppm |
| 2016-03-01 | 1471232 | ND |
| 2016-03-01 | 1471234 | ND |
| 2016-03-01 | 1471235 | ND |
| 2016-03-01 | 1471250 | 0.764 ppm |
| 2016-04-05 | 1480967 | 0.678 ppm |
| 2016-04-12 | 1482273 | 0.761 ppm |
| 2016-04-12 | 1482274 | 0.503 ppm |
| 2016-05-10 | 1490264 | 0.543 ppm |
| 2016-05-17 | 1492324 | 0.861 ppm |
| 2016-06-02 | 1496451 | 0.939 ppm |
| 2016-07-05 | 1504886 | 0.672 ppm |
| 2016-08-09 | 1515043 | 0.746 ppm |
| 2016-09-02 | 1522222 | 0.893 ppm |
| 2016-10-03 | 1529620 | 0.725 ppm |
| 2016-10-14 | 1533748 | 0.386 ppm |
| 2016-10-14 | 1533749 | 0.329 ppm |
| 2016-10-14 | 1533750 | 0.429 ppm |
| 2016-10-17 | 1533751 | 0.348 ppm |
| 2016-11-07 | 1539001 | 0.412 ppm |
| 2016-12-01 | 1544959 | 0.464 ppm |
| 2017-01-05 | 1553374 | 0.662 ppm |
| 2017-02-02 | 1560949 | 0.325 ppm |
| 2017-02-23 | 1566722 | 0.246 ppm |
| 2017-03-06 | 1569520 | 0.648 ppm |
| 2017-04-04 | 1576614 | 0.300 ppm |
| 2017-04-11 | 1578809 | 0.635 ppm |
| 2017-05-04 | 1585573 | 0.885 ppm |
| 2017-06-01 | 1592670 | 0.580 ppm |
| 2017-07-11 | 1603146 | 0.221 ppm |
| 2017-07-11 | 1603148 | 0.325 ppm |
| 2017-07-11 | 1603151 | 0.560 ppm |
| 2017-08-02 | 1610061 | 0.530 ppm |
| 2017-08-23 | 1616015 | 0.170 ppm |
| 2017-08-23 | 1616016 | 0.145 ppm |
| 2017-08-23 | 1616017 | 0.230 ppm |
| 2017-09-05 | 1619075 | 0.220 ppm |
| 2017-09-05 | 1619077 | 0.175 ppm |
| 2017-09-05 | 1619078 | 0.235 ppm |
| 2017-09-05 | 1619079 | 0.410 ppm |
| 2017-09-05 | 1620582 | 0.506 ppm |
| 2017-10-09 | 1628520 | 0.461 ppm |
| 2017-10-09 | 1628522 | 0.468 ppm |
| 2017-10-09 | 1628527 | 0.187 ppm |
| 2017-10-09 | 1628528 | 0.354 ppm |
| 2017-10-09 | 1628529 | 0.122 ppm |
| 2017-10-09 | 1628530 | 0.311 ppm |
| 2017-10-09 | 1628531 | 0.179 ppm |
| 2017-10-09 | 1628532 | 0.265 ppm |
| 2017-10-09 | 1628533 | 0.267 ppm |
| 2017-11-07 | 1636451 | 0.479 ppm |
| 2017-11-13 | 1638065 | 0.326 ppm |
| 2017-11-13 | 1638071 | 0.591 ppm |
| 2017-12-04 | 1643053 | 0.654 ppm |
| 2018-01-03 | 1650688 | 0.686 ppm |
| 2018-02-21 | 1663784 | 0.586 ppm |
| 2018-03-06 | 1666692 | 0.596 ppm |
| 2018-04-04 | 1674819 | 0.781 ppm |
| 2018-05-01 | 1681116 | 0.508 ppm |
| 2018-06-04 | 1689535 | 0.602 ppm |
| 2018-07-02 | 1697624 | 0.576 ppm |
| 2018-08-02 | AH02082-01 | 0.650 ppm |
| 2018-09-06 | AI06139-03 | 0.510 ppm |
| 2018-10-05 | AJ05018-01 | 0.730 ppm |
| 2018-11-06 | AK06114-03 | 0.610 ppm |
| 2018-12-06 | AL06087-03 | 0.590 ppm |
| 2019-01-03 | BA03045-03 | 0.550 ppm |
| 2019-02-07 | BB07047-03 | 0.540 ppm |
| 2019-03-07 | BC12026-12 | 0.510 ppm |
| 2019-04-04 | BD04048-05 | 0.420 ppm |
| 2019-05-09 | BE09051-01 | 0.590 ppm |
| 2019-05-28 | BE30060-02 | 0.280 ppm |
| 2019-06-06 | BF06058-09 | 0.520 ppm |
| 2019-07-11 | BG11116-07 | 0.600 ppm |
| 2019-08-08 | BH08059-01 | 0.610 ppm |
| 2019-09-05 | BI05081-01 | 0.220 ppm |
| 2019-10-03 | BJ03053-01 | 0.160 ppm |
| 2019-11-14 | BK14097-02 | 0.630 ppm |
| 2019-12-12 | BL12071-01 | 0.610 ppm |