Fluoride
City of Glendale
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 |
---|---|---|---|---|
2013 | N/A | 0 | 0 | N/A |
2014 | 0.386 ppm | 12 | 10 | ND - 0.660 ppm |
2015 | 0.270 ppm | 3 | 2 | ND - 0.450 ppm |
2016 | 0.461 ppm | 12 | 11 | ND - 0.700 ppm |
2017 | 0.479 ppm | 11 | 11 | 0.170 ppm - 0.680 ppm |
2018 | 0.359 ppm | 11 | 9 | ND - 0.603 ppm |
2019 | 0.303 ppm | 10 | 7 | ND - 0.588 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 |
---|---|---|
2014-01-02 | 201401020046I | 0.410 ppm |
2014-01-06 | 1401061121OSF | 0.660 ppm |
2014-01-06 | 1401060900PPF | 0.300 ppm |
2014-01-16 | 1401161225A22 | 0.410 ppm |
2014-01-16 | 1401161005CB1 | ND |
2014-05-15 | 1405151035W43I | 0.590 ppm |
2014-05-15 | 1405150920W30 | 0.580 ppm |
2014-05-21 | 1405211250CZ1 | 0.310 ppm |
2014-05-21 | 1405211210W16 | 0.630 ppm |
2014-05-21 | 1405211140W27 | ND |
2014-05-27 | 1405271200CHB | 0.350 ppm |
2014-07-18 | 1407181055W18 | 0.390 ppm |
2015-04-06 | 1504061040OSF | 0.450 ppm |
2015-04-06 | 1504061200CZ1 | ND |
2015-04-06 | 1504061325PPF | 0.360 ppm |
2016-04-18 | 1604181055W22 | 0.360 ppm |
2016-04-18 | 1604180950W30 | 0.590 ppm |
2016-04-19 | 1604191030A22 | 0.480 ppm |
2016-04-19 | 1604190950W27 | 0.300 ppm |
2016-04-21 | 1604211048W43 | 0.510 ppm |
2016-04-21 | 1604210935CHB | 0.460 ppm |
2016-04-25 | 1604251114CZ1 | 0.600 ppm |
2016-04-25 | 1604250953OSF | 0.700 ppm |
2016-04-25 | 1604250855PPF | 0.610 ppm |
2016-04-27 | 1604271045W16 | 0.560 ppm |
2016-04-29 | 1604290935W18 | 0.360 ppm |
2016-06-09 | 1606091220CB1 | ND |
2017-04-03 | 201704030392I | 0.680 ppm |
2017-04-03 | 201704030394I | 0.490 ppm |
2017-04-03 | 201704030393I | 0.570 ppm |
2017-04-19 | 201704190434I | 0.600 ppm |
2017-04-19 | 201704190433I | 0.480 ppm |
2017-04-19 | 201704190432I | 0.550 ppm |
2017-04-19 | 201704190431I | 0.320 ppm |
2017-04-26 | 201704260364I | 0.370 ppm |
2017-04-26 | 201704260363I | 0.540 ppm |
2017-04-27 | 201704270335I | 0.500 ppm |
2017-05-16 | 201705160653I | 0.170 ppm |
2018-02-28 | 1802281235PPF | 0.344 ppm |
2018-02-28 | 1802281018W27 | 0.312 ppm |
2018-02-28 | 1802280941W30 | 0.603 ppm |
2018-04-10 | 1804100946A22 | 0.422 ppm |
2018-04-11 | 1804111024CZ1 | 0.510 ppm |
2018-04-11 | 1804111048OSF | ND |
2018-04-12 | 1804121302W43 | 0.495 ppm |
2018-04-12 | 1804121158CB1 | ND |
2018-04-12 | 1804121100W16 | 0.395 ppm |
2018-04-12 | 1804120932CHB | 0.524 ppm |
2018-04-24 | 1804240917W22 | 0.343 ppm |
2019-04-15 | 1904151258PPFI | 0.352 ppm |
2019-04-15 | 1904151118CZ1FI | 0.394 ppm |
2019-04-15 | 1904150959OSFI | ND |
2019-04-18 | 1904181345A22R | 0.464 ppm |
2019-04-18 | 1904181226CB1FI | ND |
2019-04-18 | 1904181120W16FI | ND |
2019-04-18 | 1904180955CHBFI | 0.483 ppm |
2019-04-18 | 1904180915W30F | 0.588 ppm |
2019-04-19 | 1904190841W27F | 0.310 ppm |
2019-05-02 | 1905020914W43F | 0.437 ppm |