Fluoride
City of Tyler
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 | 0.253 ppm | 8 | 8 | 0.0975 ppm - 0.659 ppm |
2015 | 0.464 ppm | 2 | 2 | 0.411 ppm - 0.516 ppm |
2016 | 0.167 ppm | 3 | 1 | ND - 0.501 ppm |
2017 | 0.1000 ppm | 5 | 5 | 0.0412 ppm - 0.228 ppm |
2018 | 0.307 ppm | 2 | 2 | 0.0740 ppm - 0.540 ppm |
2019 | 0.291 ppm | 2 | 2 | 0.0385 ppm - 0.544 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 |
---|---|---|
2014-03-31 | Q1410257004 | 0.132 ppm |
2014-06-18 | Q1421982005 | 0.659 ppm |
2014-06-18 | Q1421982004 | 0.524 ppm |
2014-06-18 | Q1421982003 | 0.123 ppm |
2014-06-18 | Q1421982002 | 0.254 ppm |
2014-12-03 | Q1458264019 | 0.114 ppm |
2014-12-03 | Q1458264004 | 0.0975 ppm |
2014-12-03 | Q1458264003 | 0.120 ppm |
2015-02-26 | Q1507535006 | 0.516 ppm |
2015-02-26 | Q1507535005 | 0.411 ppm |
2016-01-07 | Q1600562014 | ND |
2016-01-07 | Q1600562013 | 0.501 ppm |
2016-04-07 | Q1613869018 | ND |
2017-01-19 | Q1702466002 | 0.0412 ppm |
2017-05-02 | Q1718006004 | 0.228 ppm |
2017-05-02 | Q1718006003 | 0.0996 ppm |
2017-11-09 | Q1757796002 | 0.0477 ppm |
2017-11-09 | Q1757796011 | 0.0835 ppm |
2018-06-26 | Q1825822006 | 0.0740 ppm |
2018-06-26 | Q1825822005 | 0.540 ppm |
2019-01-16 | Q1902313005 | 0.544 ppm |
2019-01-16 | Q1902313006 | 0.0385 ppm |