Fluoride
Yonkers City
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 | 0.659 ppm | 4 | 3 | ND - 0.880 ppm |
2015 | N/A | 0 | 0 | N/A |
2016 | 0.497 ppm | 4 | 3 | ND - 0.667 ppm |
2017 | 0.646 ppm | 4 | 4 | 0.645 ppm - 0.648 ppm |
2018 | 0.526 ppm | 4 | 3 | ND - 0.712 ppm |
2019 | 0.511 ppm | 4 | 3 | ND - 0.684 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 |
---|---|---|
2014-03-20 | 14-4421 INP | 0.877 ppm |
2014-03-20 | 14-4423 INP | 0.879 ppm |
2014-03-20 | 14-2242 INP | 0.880 ppm |
2014-03-20 | 14-4422 INP | ND |
2016-06-22 | 16-8293 INP | 0.660 ppm |
2016-06-22 | 16-8291 INP | 0.661 ppm |
2016-06-22 | 16-8292 INP | ND |
2016-06-27 | 16-8485 INP | 0.667 ppm |
2017-03-07 | 17-2237-INP | 0.646 ppm |
2017-03-07 | 17-2254-INP | 0.645 ppm |
2017-03-07 | 17-2256-INP | 0.648 ppm |
2017-03-07 | 17-2255-INP | 0.645 ppm |
2018-05-15 | 18-5003-INP | ND |
2018-05-15 | 18-5027-INP | 0.703 ppm |
2018-05-15 | 18-5024-INP | 0.712 ppm |
2018-05-29 | 18-5551-INP | 0.688 ppm |
2019-05-16 | 19-5075 INP | ND |
2019-05-16 | 19-5073 INP | 0.684 ppm |
2019-05-16 | 19-5076 INP | 0.678 ppm |
2019-05-16 | 19-5074 INP | 0.681 ppm |