Fluoride
Rockford
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 | 1.03 ppm | 22 | 22 | 0.879 ppm - 1.20 ppm |
| 2015 | 1.23 ppm | 3 | 3 | 1.03 ppm - 1.46 ppm |
| 2016 | 0.670 ppm | 2 | 2 | 0.670 ppm |
| 2017 | 0.738 ppm | 23 | 23 | 0.576 ppm - 0.829 ppm |
| 2018 | 0.315 ppm | 9 | 7 | ND - 0.829 ppm |
| 2019 | 0.726 ppm | 1 | 1 | 0.726 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 |
|---|---|---|
| 2014-01-09 | 4012110-12 | 1.10 ppm |
| 2014-01-09 | 4012110-09 | 0.932 ppm |
| 2014-01-21 | 4012700-06 | 1.01 ppm |
| 2014-01-21 | 4012700-05 | 1.11 ppm |
| 2014-01-21 | 4012700-04 | 1.12 ppm |
| 2014-01-22 | 4012700-01 | 1.06 ppm |
| 2014-01-27 | 4013503-02 | 0.986 ppm |
| 2014-01-28 | 4013503-01 | 1.20 ppm |
| 2014-01-31 | 4020631-04 | 0.882 ppm |
| 2014-01-31 | 4020631-05 | 1.06 ppm |
| 2014-01-31 | 4020631-01 | 0.896 ppm |
| 2014-02-18 | 4022297-01 | 1.20 ppm |
| 2014-02-18 | 4022291-01 | 1.09 ppm |
| 2014-02-18 | 4022289-01 | 1.16 ppm |
| 2014-02-18 | 4022297-02 | 0.879 ppm |
| 2014-02-25 | 4023202-01 | 1.06 ppm |
| 2014-07-01 | 4070553-01 | 0.931 ppm |
| 2014-07-23 | 4073622-04 | 1.04 ppm |
| 2014-07-23 | 4073622-01 | 1.02 ppm |
| 2014-10-28 | 4104357-01 | 1.03 ppm |
| 2014-12-05 | 4121752-01 | 0.943 ppm |
| 2014-12-12 | 4122805-01 | 0.888 ppm |
| 2015-01-28 | 5013651-04 | 1.46 ppm |
| 2015-04-15 | 5042507-02 | 1.19 ppm |
| 2015-06-17 | 5062896-01 | 1.03 ppm |
| 2016-10-12 | 6102040-01 | 0.670 ppm |
| 2016-12-14 | 6122205-01 | 0.670 ppm |
| 2017-01-06 | 7011622-01 | 0.704 ppm |
| 2017-01-06 | 7011622-02 | 0.786 ppm |
| 2017-01-13 | 7012600-01 | 0.702 ppm |
| 2017-01-13 | 7012603-03 | 0.744 ppm |
| 2017-01-13 | 7012600-02 | 0.576 ppm |
| 2017-01-13 | 7012603-02 | 0.710 ppm |
| 2017-01-13 | 7012603-01 | 0.704 ppm |
| 2017-01-13 | 7012600-04 | 0.760 ppm |
| 2017-01-20 | 7013468-02 | 0.696 ppm |
| 2017-01-20 | 7013468-01 | 0.791 ppm |
| 2017-01-20 | 7013468-04 | 0.796 ppm |
| 2017-02-03 | 7021369-01 | 0.737 ppm |
| 2017-02-03 | 7021369-02 | 0.721 ppm |
| 2017-02-10 | 7022427-01 | 0.773 ppm |
| 2017-03-08 | 7031384-01 | 0.744 ppm |
| 2017-05-26 | 7055219-01 | 0.762 ppm |
| 2017-07-24 | 7075084-07 | 0.714 ppm |
| 2017-07-24 | 7075084-06 | 0.765 ppm |
| 2017-07-24 | 7075084-03 | 0.737 ppm |
| 2017-07-24 | 7075084-02 | 0.679 ppm |
| 2017-07-24 | 7075084-05 | 0.758 ppm |
| 2017-10-13 | 7103385-03 | 0.797 ppm |
| 2017-12-06 | 7121184-03 | 0.829 ppm |
| 2018-01-29 | 18A0571-01_02 | 0.145 ppm |
| 2018-01-29 | 18A0571-02_02 | 0.196 ppm |
| 2018-04-06 | 8042289-03 | 0.690 ppm |
| 2018-04-18 | 8043420-02 | 0.764 ppm |
| 2018-05-30 | 18E1190-01_02 | 0.0990 ppm |
| 2018-06-12 | 8062626-01 | 0.829 ppm |
| 2018-10-31 | 18K0014-01_02 | ND |
| 2018-12-05 | 18L0178-01_02 | 0.112 ppm |
| 2018-12-05 | 18L0178-02_02 | ND |
| 2019-11-08 | 9112291-01 | 0.726 ppm |