Fluoride
City of Kearney
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 | 0.807 ppm | 13 | 13 | 0.731 ppm - 0.914 ppm |
2015 | 0.952 ppm | 13 | 13 | 0.857 ppm - 1.03 ppm |
2016 | 0.905 ppm | 14 | 14 | 0.335 ppm - 1.01 ppm |
2017 | 0.896 ppm | 13 | 13 | 0.808 ppm - 0.991 ppm |
2018 | 0.924 ppm | 13 | 13 | 0.835 ppm - 0.979 ppm |
2019 | 0.873 ppm | 14 | 14 | 0.781 ppm - 0.959 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 |
---|---|---|
2014-01-06 | 280692 | 0.756 ppm |
2014-02-03 | 285739 | 0.731 ppm |
2014-03-10 | 289600 | 0.758 ppm |
2014-04-07 | 293046 | 0.793 ppm |
2014-05-05 | 298870 | 0.749 ppm |
2014-06-02 | 304959 | 0.793 ppm |
2014-07-07 | 308799 | 0.822 ppm |
2014-07-14 | 311394 | 0.742 ppm |
2014-08-04 | 316669 | 0.881 ppm |
2014-09-02 | 322321 | 0.849 ppm |
2014-10-06 | 327246 | 0.833 ppm |
2014-11-12 | 334668 | 0.865 ppm |
2014-12-01 | 338149 | 0.914 ppm |
2015-01-12 | 342179 | 0.924 ppm |
2015-02-09 | 347809 | 0.968 ppm |
2015-03-02 | 350664 | 0.914 ppm |
2015-04-13 | 355548 | 0.928 ppm |
2015-05-11 | 363340 | 0.916 ppm |
2015-06-01 | 367618 | 0.857 ppm |
2015-07-13 | 371910 | 1.000 ppm |
2015-07-20 | 377037 | 0.966 ppm |
2015-08-10 | 380133 | 1.01 ppm |
2015-09-08 | 385380 | 1.03 ppm |
2015-10-13 | 390401 | 0.976 ppm |
2015-11-16 | 397362 | 0.942 ppm |
2015-12-07 | 401269 | 0.940 ppm |
2016-01-04 | 0.958 ppm | |
2016-01-04 | 0.335 ppm | |
2016-02-01 | 0.813 ppm | |
2016-03-07 | 0.851 ppm | |
2016-04-11 | 0.912 ppm | |
2016-05-09 | 0.961 ppm | |
2016-06-13 | 0.895 ppm | |
2016-07-11 | 0.996 ppm | |
2016-07-18 | 0.992 ppm | |
2016-08-15 | 1.01 ppm | |
2016-09-06 | 0.995 ppm | |
2016-10-17 | 0.962 ppm | |
2016-11-07 | 0.993 ppm | |
2016-12-12 | 0.993 ppm | |
2017-01-09 | 0.924 ppm | |
2017-02-06 | 0.868 ppm | |
2017-03-13 | 0.920 ppm | |
2017-04-10 | 0.991 ppm | |
2017-05-08 | 0.808 ppm | |
2017-06-12 | 0.901 ppm | |
2017-07-10 | 0.852 ppm | |
2017-07-31 | 0.919 ppm | |
2017-08-08 | 0.894 ppm | |
2017-09-11 | 0.906 ppm | |
2017-10-09 | 0.933 ppm | |
2017-11-13 | 0.889 ppm | |
2017-12-04 | 0.849 ppm | |
2018-01-08 | 530329 | 0.923 ppm |
2018-02-12 | 535904 | 0.900 ppm |
2018-03-13 | 539359 | 0.910 ppm |
2018-04-02 | 542703 | 0.879 ppm |
2018-05-07 | 548909 | 0.893 ppm |
2018-06-05 | 554103 | 0.835 ppm |
2018-07-09 | 558791 | 0.944 ppm |
2018-07-09 | 562080 | 0.938 ppm |
2018-08-13 | 566539 | 0.960 ppm |
2018-09-07 | 570713 | 0.979 ppm |
2018-10-02 | 576672 | 0.946 ppm |
2018-11-19 | 582169 | 0.972 ppm |
2018-12-03 | 585968 | 0.938 ppm |
2019-01-07 | 589414 | 0.927 ppm |
2019-01-07 | 592499 | 0.781 ppm |
2019-02-04 | 594841 | 0.959 ppm |
2019-03-04 | 598216 | 0.908 ppm |
2019-04-09 | 602110 | 0.877 ppm |
2019-05-14 | 609739 | 0.861 ppm |
2019-06-10 | 613628 | 0.832 ppm |
2019-07-01 | 619749 | 0.842 ppm |
2019-07-09 | 621937 | 0.843 ppm |
2019-08-13 | 627432 | 0.882 ppm |
2019-09-09 | 631611 | 0.883 ppm |
2019-10-14 | 636906 | 0.920 ppm |
2019-11-05 | 643654 | 0.893 ppm |
2019-12-10 | 648263 | 0.809 ppm |