Fluoride
City of Chesapeake - Northwest River System
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 | 0.973 ppm | 26 | 26 | 0.640 ppm - 1.10 ppm |
2015 | 0.880 ppm | 27 | 27 | 0.680 ppm - 1.11 ppm |
2016 | 0.831 ppm | 27 | 27 | 0.703 ppm - 0.962 ppm |
2017 | 0.765 ppm | 33 | 33 | 0.620 ppm - 0.927 ppm |
2018 | 0.850 ppm | 2 | 2 | 0.780 ppm - 0.920 ppm |
2019 | 0.825 ppm | 2 | 2 | 0.800 ppm - 0.850 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 |
---|---|---|
2014-01-08 | 14-0108-NWR | 1.000 ppm |
2014-01-08 | 14-0108-LG | 1.000 ppm |
2014-01-27 | 14-01148-INO | 1.04 ppm |
2014-02-12 | 14-0212-NWR | 1.000 ppm |
2014-02-12 | 14-0212-LG | 1.000 ppm |
2014-03-06 | 14-0306-NWR | 1.000 ppm |
2014-03-12 | 14-0312-LG | 1.000 ppm |
2014-04-08 | 234920 | 1.000 ppm |
2014-04-08 | 234919 | 0.900 ppm |
2014-05-08 | 247942 | 1.000 ppm |
2014-05-08 | 247943 | 0.900 ppm |
2014-06-10 | 259827 | 0.900 ppm |
2014-06-10 | 259826 | 0.800 ppm |
2014-07-09 | 270680 | 1.10 ppm |
2014-07-09 | 270679 | 1.000 ppm |
2014-08-13 | 282792 | 1.10 ppm |
2014-08-13 | 282793 | 1.000 ppm |
2014-08-20 | E140800081 | 0.870 ppm |
2014-09-08 | 293995 | 1.10 ppm |
2014-09-08 | 293996 | 1.000 ppm |
2014-10-08 | 305387 | 1.10 ppm |
2014-10-08 | 305388 | 1.000 ppm |
2014-11-12 | 320331 | 0.920 ppm |
2014-11-12 | 320330 | 0.640 ppm |
2014-12-08 | 332113 | 1.05 ppm |
2014-12-08 | 332114 | 0.890 ppm |
2015-01-08 | 460011-CENTRAL E | 1.000 ppm |
2015-01-08 | 460011-CENTRAL E | 0.900 ppm |
2015-01-27 | VA010-DCLS | 1.000 ppm |
2015-01-27 | VA010-DCLS | 0.990 ppm |
2015-02-09 | 460011-CENTRAL E | 0.950 ppm |
2015-02-09 | 460011-CENTRAL E | 0.820 ppm |
2015-03-10 | 460011-CENTRAL E | 0.990 ppm |
2015-03-10 | 460011-CENTRAL E | 0.850 ppm |
2015-04-08 | 460011-CENTRAL E | 1.11 ppm |
2015-04-08 | 460011-CENTRAL E | 0.820 ppm |
2015-05-11 | 460011-CENTRAL E | 0.800 ppm |
2015-05-11 | 460011-CENTRAL E | 0.680 ppm |
2015-06-15 | 460011-CENTRAL E | 0.930 ppm |
2015-06-15 | 460011-CENTRAL E | 0.910 ppm |
2015-07-13 | 460011-CENTRAL E | 0.936 ppm |
2015-07-13 | 460011-CENTRAL E | 0.914 ppm |
2015-08-10 | 460011-CENTRAL E | 0.922 ppm |
2015-08-10 | 460011-CENTRAL E | 0.762 ppm |
2015-08-18 | VA010-DCLS | 0.920 ppm |
2015-09-09 | 460011-CENTRAL E | 0.920 ppm |
2015-09-09 | 460011-CENTRAL E | 0.702 ppm |
2015-10-07 | 460011-CENTRAL E | 0.986 ppm |
2015-10-07 | 460011-CENTRAL E | 0.875 ppm |
2015-11-10 | 460011-CENTRAL E | 0.786 ppm |
2015-11-10 | 460011-CENTRAL E | 0.751 ppm |
2015-12-07 | 460011-CENTRAL E | 0.780 ppm |
2015-12-07 | 460011-CENTRAL E | 0.769 ppm |
2016-01-12 | 497239 | 0.774 ppm |
2016-01-12 | 497240 | 0.720 ppm |
2016-01-25 | E160103278 | 0.960 ppm |
2016-02-10 | 510639 | 0.795 ppm |
2016-02-10 | 510640 | 0.748 ppm |
2016-03-08 | 523547 | 0.802 ppm |
2016-03-08 | 523548 | 0.791 ppm |
2016-04-13 | 542678 | 0.760 ppm |
2016-04-13 | 542679 | 0.703 ppm |
2016-05-11 | 557501 | 0.787 ppm |
2016-05-11 | 557502 | 0.752 ppm |
2016-06-15 | 574814 | 0.962 ppm |
2016-06-15 | 574813 | 0.842 ppm |
2016-07-13 | 590417 | 0.930 ppm |
2016-07-13 | 590418 | 0.860 ppm |
2016-08-10 | 606773 | 0.858 ppm |
2016-08-10 | 606772 | 0.838 ppm |
2016-08-22 | E160802676 | 0.870 ppm |
2016-08-22 | E160802678 | 0.860 ppm |
2016-09-14 | 626684 | 0.950 ppm |
2016-09-14 | 626683 | 0.826 ppm |
2016-10-19 | 648440 | 0.810 ppm |
2016-10-19 | 648439 | 0.885 ppm |
2016-11-09 | 660001 | 0.929 ppm |
2016-11-09 | 660002 | 0.861 ppm |
2016-12-06 | 675398 | 0.799 ppm |
2016-12-06 | 675397 | 0.753 ppm |
2017-01-11 | 694504 | 0.802 ppm |
2017-01-11 | 694503 | 0.679 ppm |
2017-02-13 | E170100166 | 0.780 ppm |
2017-02-13 | E170100163 | 0.770 ppm |
2017-02-13 | E170100164 | 0.770 ppm |
2017-02-13 | 714325 | 0.770 ppm |
2017-02-13 | E170100162 | 0.760 ppm |
2017-02-13 | E170100161 | 0.790 ppm |
2017-02-13 | E170100165 | 0.790 ppm |
2017-02-13 | E170100167 | 0.790 ppm |
2017-02-13 | 714326 | 0.740 ppm |
2017-03-15 | 728757 | 0.631 ppm |
2017-03-15 | 728756 | 0.620 ppm |
2017-04-12 | 749011 | 0.752 ppm |
2017-04-12 | 749012 | 0.681 ppm |
2017-05-10 | 766048 | 0.756 ppm |
2017-05-10 | 766049 | 0.737 ppm |
2017-06-07 | 781723 | 0.819 ppm |
2017-06-07 | 781724 | 0.829 ppm |
2017-07-12 | 802450 | 0.854 ppm |
2017-07-12 | 802449 | 0.843 ppm |
2017-08-01 | E170701931 | 0.890 ppm |
2017-08-01 | E170701929 | 0.880 ppm |
2017-08-09 | 819549 | 0.781 ppm |
2017-08-09 | 819550 | 0.927 ppm |
2017-09-06 | 835889 | 0.717 ppm |
2017-09-06 | 835888 | 0.671 ppm |
2017-10-11 | 856838 | 0.793 ppm |
2017-10-11 | 856837 | 0.724 ppm |
2017-11-08 | 873873 | 0.709 ppm |
2017-11-08 | 873874 | 0.845 ppm |
2017-12-13 | 893241 | 0.687 ppm |
2017-12-13 | 893240 | 0.662 ppm |
2018-02-12 | E180102304 | 0.920 ppm |
2018-08-21 | E180802579 | 0.780 ppm |
2019-01-28 | E181206806 | 0.800 ppm |
2019-08-26 | E190802876 | 0.850 ppm |