Fluoride
Marion Waterworks
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 | 0.718 ppm | 36 | 36 | 0.320 ppm - 1.15 ppm |
2015 | 0.691 ppm | 40 | 38 | ND - 0.970 ppm |
2016 | 0.759 ppm | 35 | 35 | 0.520 ppm - 1.000 ppm |
2017 | 0.804 ppm | 30 | 30 | 0.710 ppm - 0.990 ppm |
2018 | 0.805 ppm | 31 | 30 | ND - 1.11 ppm |
2019 | 0.663 ppm | 24 | 24 | 0.550 ppm - 0.940 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 |
---|---|---|
2014-01-28 | 140340002 | 0.750 ppm |
2014-01-28 | 140340003 | 0.750 ppm |
2014-01-28 | 140340004 | 0.800 ppm |
2014-02-05 | 140410021 | 0.320 ppm |
2014-02-10 | 140490006 | 0.790 ppm |
2014-02-10 | 140490007 | 0.700 ppm |
2014-03-18 | 140900018 | 0.740 ppm |
2014-03-18 | 140900016 | 0.770 ppm |
2014-03-18 | 140900017 | 0.830 ppm |
2014-04-14 | 141110008 | 0.590 ppm |
2014-04-14 | 141110007 | 0.590 ppm |
2014-04-14 | 141110006 | 0.610 ppm |
2014-05-21 | 141470019 | 0.580 ppm |
2014-05-21 | 141470020 | 0.540 ppm |
2014-05-21 | 141470021 | 0.520 ppm |
2014-06-03 | 141600015 | 0.500 ppm |
2014-06-03 | 141600014 | 0.590 ppm |
2014-06-03 | 141600013 | 0.500 ppm |
2014-07-15 | 142020010 | 0.660 ppm |
2014-07-15 | 142020011 | 0.660 ppm |
2014-07-15 | 142020009 | 0.640 ppm |
2014-08-19 | 142370007 | 0.500 ppm |
2014-08-19 | 142370009 | 0.550 ppm |
2014-08-19 | 142370008 | 0.500 ppm |
2014-09-23 | 142720014 | 0.660 ppm |
2014-09-23 | 142720015 | 0.660 ppm |
2014-09-26 | 142720013 | 0.660 ppm |
2014-10-22 | Y143000036 | 0.930 ppm |
2014-10-22 | Y143000035 | 0.840 ppm |
2014-10-22 | Y143000037 | 0.970 ppm |
2014-11-05 | Y143110029 | 0.890 ppm |
2014-11-05 | Y143110031 | 1.05 ppm |
2014-11-05 | Y143110030 | 0.980 ppm |
2014-12-08 | Y143490026 | 1.06 ppm |
2014-12-08 | Y143490028 | 1.15 ppm |
2014-12-08 | Y143490027 | 1.000 ppm |
2015-01-22 | Y150260023 | 0.680 ppm |
2015-01-22 | Y150260022 | 0.860 ppm |
2015-01-22 | Y150260024 | 0.970 ppm |
2015-01-27 | Y150330018 | 0.460 ppm |
2015-02-24 | Y150610020 | 0.800 ppm |
2015-02-24 | Y150610021 | 0.860 ppm |
2015-02-24 | Y150610019 | 0.920 ppm |
2015-03-30 | Y150960010 | 0.510 ppm |
2015-03-30 | Y150960012 | 0.570 ppm |
2015-03-30 | Y150960011 | 0.530 ppm |
2015-04-30 | Y151280013 | 0.350 ppm |
2015-04-30 | Y151280011 | 0.360 ppm |
2015-04-30 | Y151280012 | 0.430 ppm |
2015-05-06 | Y151340021 | 0.630 ppm |
2015-05-06 | Y151340022 | 0.630 ppm |
2015-05-06 | Y151340020 | 0.640 ppm |
2015-06-30 | Y151890003 | 0.870 ppm |
2015-06-30 | Y151890004 | 0.940 ppm |
2015-06-30 | Y151890005 | 0.780 ppm |
2015-07-09 | Y151950013 | 0.720 ppm |
2015-07-09 | Y151950015 | 0.700 ppm |
2015-07-09 | Y151950014 | 0.720 ppm |
2015-08-05 | Y152260039 | 0.860 ppm |
2015-08-05 | Y152260046 | 0.880 ppm |
2015-08-05 | Y152260050 | 0.830 ppm |
2015-09-16 | Y152600001 | ND |
2015-09-16 | Y152600003 | 0.520 ppm |
2015-09-22 | Y152710014 | 0.890 ppm |
2015-09-22 | Y152710012 | 0.840 ppm |
2015-09-22 | Y152710013 | 0.830 ppm |
2015-10-07 | Y152850038 | 0.920 ppm |
2015-10-07 | Y152850039 | 0.820 ppm |
2015-10-07 | Y152850037 | 0.860 ppm |
2015-11-19 | Y153240001 | ND |
2015-11-25 | Y153340025 | 0.620 ppm |
2015-11-25 | Y153340023 | 0.620 ppm |
2015-11-25 | Y153340004 | 0.660 ppm |
2015-12-08 | Y153480027 | 0.860 ppm |
2015-12-08 | Y153480028 | 0.850 ppm |
2015-12-08 | Y153480026 | 0.860 ppm |
2016-01-12 | Y160200034 | 0.950 ppm |
2016-01-12 | Y160200035 | 1.000 ppm |
2016-01-12 | Y160200036 | 1.000 ppm |
2016-02-08 | Y160470021 | 0.890 ppm |
2016-02-08 | Y160470022 | 0.860 ppm |
2016-02-08 | Y160470023 | 0.840 ppm |
2016-02-15 | Y160530006 | 0.580 ppm |
2016-03-07 | Y160680012 | 0.520 ppm |
2016-03-07 | Y160680013 | 0.540 ppm |
2016-03-07 | Y160680015 | 0.540 ppm |
2016-04-11 | Y161060042 | 0.820 ppm |
2016-04-11 | Y161060043 | 0.820 ppm |
2016-04-11 | Y161060044 | 0.820 ppm |
2016-05-10 | Y161380026 | 0.660 ppm |
2016-05-11 | Y161380025 | 0.640 ppm |
2016-05-11 | Y161380027 | 0.640 ppm |
2016-06-06 | Y161650011 | 0.720 ppm |
2016-06-06 | Y161650017 | 0.700 ppm |
2016-06-06 | Y161650018 | 0.670 ppm |
2016-07-11 | Y162000038 | 0.760 ppm |
2016-07-11 | Y162000039 | 0.790 ppm |
2016-07-11 | Y162000040 | 0.780 ppm |
2016-08-02 | Y162170008 | 0.770 ppm |
2016-08-02 | Y162170009 | 0.810 ppm |
2016-08-02 | Y162170010 | 0.840 ppm |
2016-09-12 | Y162640025 | 0.780 ppm |
2016-09-12 | Y162640033 | 0.790 ppm |
2016-09-12 | Y162640041 | 0.770 ppm |
2016-10-05 | Y162880062 | 0.620 ppm |
2016-10-05 | Y162880063 | 0.720 ppm |
2016-10-05 | Y162880043 | 0.670 ppm |
2016-11-17 | Y163260011 | 0.770 ppm |
2016-11-17 | Y163260012 | 0.760 ppm |
2016-11-17 | Y163260013 | 0.760 ppm |
2016-12-05 | Y163420005 | 0.970 ppm |
2017-01-17 | Y170200002 | 0.790 ppm |
2017-02-06 | Y170400071 | 0.990 ppm |
2017-02-06 | Y170400070 | 0.960 ppm |
2017-02-07 | Y170400035 | 0.780 ppm |
2017-03-13 | Y170790027 | 0.910 ppm |
2017-03-13 | Y170790028 | 0.920 ppm |
2017-04-03 | Y171000002 | 0.840 ppm |
2017-04-03 | Y171000001 | 0.850 ppm |
2017-05-08 | Y171350033 | 0.870 ppm |
2017-05-08 | Y171350032 | 0.870 ppm |
2017-06-05 | Y171630010 | 0.820 ppm |
2017-06-05 | Y171630009 | 0.820 ppm |
2017-07-10 | Y171980007 | 0.800 ppm |
2017-07-10 | Y171980008 | 0.740 ppm |
2017-08-07 | Y172260003 | 0.800 ppm |
2017-08-07 | Y172260004 | 0.800 ppm |
2017-09-18 | Y172680009 | 0.710 ppm |
2017-09-18 | Y172680010 | 0.710 ppm |
2017-10-16 | Y172960009 | 0.750 ppm |
2017-10-16 | Y172960010 | 0.790 ppm |
2017-10-16 | Y172960011 | 0.790 ppm |
2017-10-16 | Y172960012 | 0.790 ppm |
2017-11-06 | Y173170004 | 0.740 ppm |
2017-11-06 | Y173170005 | 0.740 ppm |
2017-11-06 | Y173170006 | 0.730 ppm |
2017-12-04 | Y173450011 | 0.770 ppm |
2017-12-04 | Y173450012 | 0.770 ppm |
2017-12-04 | Y173450013 | 0.770 ppm |
2017-12-04 | Y173450014 | 0.770 ppm |
2017-12-06 | Y173410001 | 0.740 ppm |
2018-01-22 | Y180240014 | 0.810 ppm |
2018-01-22 | Y180240013 | 0.860 ppm |
2018-01-22 | Y180240015 | 0.820 ppm |
2018-02-05 | Y180370022 | 0.800 ppm |
2018-02-05 | Y180370023 | 0.820 ppm |
2018-02-05 | Y180370021 | 0.820 ppm |
2018-03-27 | Y180920014 | 0.800 ppm |
2018-03-27 | Y180920013 | 0.910 ppm |
2018-03-27 | Y180920015 | 0.790 ppm |
2018-04-03 | Y180990029 | 0.790 ppm |
2018-04-03 | Y180990030 | 0.760 ppm |
2018-05-07 | Y181340005 | 0.800 ppm |
2018-05-07 | Y181340004 | 0.720 ppm |
2018-06-04 | Y181620006 | 0.860 ppm |
2018-06-04 | Y181620007 | 0.860 ppm |
2018-07-09 | Y181970049 | 0.910 ppm |
2018-07-10 | Y181970048 | 0.910 ppm |
2018-08-15 | Y182280001 | 1.10 ppm |
2018-08-15 | Y182280007 | 1.11 ppm |
2018-08-20 | Y182400004 | 0.970 ppm |
2018-08-20 | Y182400003 | 0.960 ppm |
2018-09-10 | Y182560022 | 0.800 ppm |
2018-09-17 | Y182610042 | 0.790 ppm |
2018-09-17 | Y182610041 | 0.790 ppm |
2018-10-01 | Y182750030 | 0.710 ppm |
2018-10-01 | Y182750031 | 0.710 ppm |
2018-10-15 | Y182910002 | ND |
2018-11-13 | Y183240017 | 0.740 ppm |
2018-11-13 | Y183240018 | 0.740 ppm |
2018-12-03 | Y183440011 | 0.710 ppm |
2018-12-03 | Y183440010 | 0.780 ppm |
2019-01-22 | Y190280011 | 0.710 ppm |
2019-01-22 | Y190280012 | 0.720 ppm |
2019-02-04 | Y190420008 | 0.620 ppm |
2019-02-04 | Y190420007 | 0.630 ppm |
2019-03-04 | Y190700004 | 0.640 ppm |
2019-03-04 | Y190700003 | 0.650 ppm |
2019-04-02 | Y190980024 | 0.610 ppm |
2019-04-02 | Y190980025 | 0.550 ppm |
2019-05-06 | Y191330011 | 0.610 ppm |
2019-05-06 | Y191330010 | 0.610 ppm |
2019-06-03 | Y191610014 | 0.620 ppm |
2019-06-03 | Y191610015 | 0.620 ppm |
2019-07-08 | Y191960063 | 0.620 ppm |
2019-07-08 | Y191960064 | 0.620 ppm |
2019-08-26 | Y192530007 | 0.940 ppm |
2019-08-26 | Y192530006 | 0.920 ppm |
2019-09-09 | Y192530020 | 0.640 ppm |
2019-09-09 | Y192530021 | 0.640 ppm |
2019-10-08 | Y192880067 | 0.650 ppm |
2019-10-08 | Y192880066 | 0.700 ppm |
2019-11-18 | Y193290001 | 0.620 ppm |
2019-11-18 | Y193290003 | 0.620 ppm |
2019-12-16 | Y193540011 | 0.680 ppm |
2019-12-16 | Y193540012 | 0.680 ppm |