Fluoride
North Springs Improvement District
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 | 0.594 ppm | 3 | 3 | 0.500 ppm - 0.642 ppm |
2015 | 0.500 ppm | 2 | 2 | 0.500 ppm |
2016 | 0.678 ppm | 2 | 2 | 0.678 ppm |
2017 | 0.593 ppm | 2 | 2 | 0.593 ppm |
2018 | 0.568 ppm | 7 | 7 | 0.542 ppm - 0.603 ppm |
2019 | 0.548 ppm | 20 | 20 | 0.479 ppm - 0.612 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 | Result |
---|---|
2014-04-16 | 0.500 ppm |
2014-10-07 | 0.642 ppm |
2014-10-07 | 0.641 ppm |
2015-04-16 | 0.500 ppm |
2015-04-16 | 0.500 ppm |
2016-04-20 | 0.678 ppm |
2016-04-20 | 0.678 ppm |
2017-04-13 | 0.593 ppm |
2017-04-13 | 0.593 ppm |
2018-04-24 | 0.603 ppm |
2018-04-24 | 0.603 ppm |
2018-08-06 | 0.544 ppm |
2018-10-15 | 0.563 ppm |
2018-10-15 | 0.542 ppm |
2018-12-18 | 0.559 ppm |
2018-12-18 | 0.559 ppm |
2019-02-05 | 0.560 ppm |
2019-02-05 | 0.550 ppm |
2019-03-05 | 0.541 ppm |
2019-03-05 | 0.523 ppm |
2019-04-08 | 0.550 ppm |
2019-04-08 | 0.556 ppm |
2019-04-24 | 0.590 ppm |
2019-04-24 | 0.590 ppm |
2019-05-14 | 0.585 ppm |
2019-05-14 | 0.612 ppm |
2019-06-11 | 0.479 ppm |
2019-06-11 | 0.534 ppm |
2019-07-08 | 0.510 ppm |
2019-07-08 | 0.503 ppm |
2019-09-10 | 0.542 ppm |
2019-10-08 | 0.575 ppm |
2019-10-08 | 0.575 ppm |
2019-11-12 | 0.588 ppm |
2019-12-16 | 0.486 ppm |
2019-12-16 | 0.505 ppm |