Fluoride

River Falls 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.

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260

Samples

Samples exceeding legal limit (MCL)

Samples exceeding
health guidelines

Testing results - average by year

Year	Average result	Samples taken	Detections	Range of results
2013	N/A	0	0	N/A
2014	0.824 ppm	29	29	0.673 ppm - 1.03 ppm
2015	0.867 ppm	31	31	0.630 ppm - 3.80 ppm
2016	0.684 ppm	49	49	0.130 ppm - 0.830 ppm
2017	0.696 ppm	53	53	0.140 ppm - 0.980 ppm
2018	0.740 ppm	49	49	0.130 ppm - 0.973 ppm
2019	0.653 ppm	49	49	0.130 ppm - 0.753 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
2014-01-17	116689001	0.876 ppm
2014-01-17	116689001	0.950 ppm
2014-02-20	120546001	0.840 ppm
2014-02-20	120546001	0.878 ppm
2014-03-20	124441001	0.760 ppm
2014-03-20	124441001	0.834 ppm
2014-04-21	129335001	0.720 ppm
2014-04-21	129335001	0.900 ppm
2014-05-19	134210001	0.764 ppm
2014-05-19	134210001	1.03 ppm
2014-06-11	796161	0.690 ppm
2014-06-11	796158	0.710 ppm
2014-06-11	796164	0.760 ppm
2014-06-11	796170	0.820 ppm
2014-06-11	796167	1.000 ppm
2014-06-17	140453001	0.770 ppm
2014-06-17	140453001	0.846 ppm
2014-07-23	147557001	0.826 ppm
2014-07-23	147557001	0.880 ppm
2014-08-20	153029001	0.808 ppm
2014-08-20	153029001	0.870 ppm
2014-09-22	159570001	0.896 ppm
2014-09-22	159570001	0.980 ppm
2014-10-24	165472001	0.761 ppm
2014-10-24	165472001	0.780 ppm
2014-11-21	169719001	0.673 ppm
2014-11-21	169719001	0.750 ppm
2014-12-15	173018001	0.745 ppm
2014-12-15	173018001	0.790 ppm
2015-01-16	176089001	0.780 ppm
2015-01-16	176089001	0.830 ppm
2015-02-12	180353001	0.835 ppm
2015-02-12	180353001	0.840 ppm
2015-03-10	183308001	0.840 ppm
2015-03-10	183308001	0.860 ppm
2015-04-17	189306001	0.790 ppm
2015-04-17	189306001	0.798 ppm
2015-05-15	193838001	0.830 ppm
2015-05-15	193838001	0.837 ppm
2015-06-12	199404001	0.740 ppm
2015-06-12	199404001	0.796 ppm
2015-07-08	204786001	0.690 ppm
2015-07-08	204786001	0.696 ppm
2015-08-05	210268001	0.630 ppm
2015-08-05	210268001	0.690 ppm
2015-09-10	216785001	0.668 ppm
2015-09-10	216785001	0.710 ppm
2015-09-24	885689	3.80 ppm
2015-10-12	223789001	0.670 ppm
2015-10-12	223789001	0.684 ppm
2015-10-19	225193001	0.827 ppm
2015-10-19	225193001	0.950 ppm
2015-11-10	228443001	0.690 ppm
2015-11-10	228443001	0.742 ppm
2015-11-10	228311001	0.840 ppm
2015-11-10	228311001	0.855 ppm
2015-12-07	232399001	0.675 ppm
2015-12-07	232399001	0.820 ppm
2015-12-10	232401001	0.700 ppm
2015-12-10	232401001	0.760 ppm
2016-01-12	236027001	0.679 ppm
2016-01-12	235930001	0.700 ppm
2016-01-12	235930001	0.720 ppm
2016-01-12	236027001	0.760 ppm
2016-02-08	239258001	0.660 ppm
2016-02-08	239258001	0.730 ppm
2016-02-10	239573001	0.650 ppm
2016-02-10	239573001	0.704 ppm
2016-03-07	243566001	0.813 ppm
2016-03-07	243566001	0.830 ppm
2016-03-09	243621001	0.680 ppm
2016-03-09	243621001	0.704 ppm
2016-04-07	247620001	0.571 ppm
2016-04-07	247620001	0.620 ppm
2016-04-07	247655001	0.628 ppm
2016-04-07	247655001	0.640 ppm
2016-05-09	253870001	0.541 ppm
2016-05-09	253880001	0.590 ppm
2016-05-09	253880001	0.636 ppm
2016-05-09	253870001	0.650 ppm
2016-05-31	923423	0.130 ppm
2016-06-06	259040001	0.660 ppm
2016-06-06	259040001	0.720 ppm
2016-06-09	259611001	0.710 ppm
2016-06-09	259611001	0.718 ppm
2016-07-07	264862001	0.647 ppm
2016-07-07	264861001	0.660 ppm
2016-07-07	264861001	0.688 ppm
2016-07-07	264862001	0.730 ppm
2016-08-09	271623001	0.635 ppm
2016-08-09	271623001	0.680 ppm
2016-08-11	271843001	0.690 ppm
2016-08-11	271843001	0.695 ppm
2016-09-08	276488001	0.633 ppm
2016-09-08	276488001	0.750 ppm
2016-09-13	277943001	0.685 ppm
2016-09-13	277943001	0.780 ppm
2016-10-03	282272001	0.675 ppm
2016-10-03	282272001	0.740 ppm
2016-10-10	283559001	0.696 ppm
2016-10-10	283559001	0.820 ppm
2016-11-10	289426001	0.700 ppm
2016-11-10	289426001	0.728 ppm
2016-11-10	288661001	0.750 ppm
2016-11-10	288661001	0.799 ppm
2016-12-12	293376001	0.705 ppm
2016-12-12	293376001	0.760 ppm
2016-12-13	293257001	0.718 ppm
2016-12-13	293257001	0.720 ppm
2017-01-09	296113001	0.667 ppm
2017-01-09	295856001	0.685 ppm
2017-01-09	295856001	0.730 ppm
2017-01-09	296113001	0.830 ppm
2017-02-06	299242001	0.655 ppm
2017-02-06	299242001	0.740 ppm
2017-02-09	299541001	0.744 ppm
2017-02-09	299541001	0.780 ppm
2017-03-02	302178001	0.660 ppm
2017-03-02	302178001	0.690 ppm
2017-03-09	303633001	0.696 ppm
2017-03-09	303633001	0.810 ppm
2017-04-03	307991001	0.652 ppm
2017-04-03	307966001	0.694 ppm
2017-04-03	307991001	0.710 ppm
2017-04-03	307966001	0.780 ppm
2017-05-01	986328	0.140 ppm
2017-05-01	313814001	0.685 ppm
2017-05-01	313814001	0.980 ppm
2017-05-02	986332	0.550 ppm
2017-05-02	313687001	0.647 ppm
2017-05-02	986340	0.660 ppm
2017-05-02	986344	0.690 ppm
2017-05-02	313687001	0.710 ppm
2017-05-02	986336	0.820 ppm
2017-06-01	319195001	0.686 ppm
2017-06-01	319196001	0.696 ppm
2017-06-01	319195001	0.770 ppm
2017-06-01	319196001	0.820 ppm
2017-07-03	325747001	0.659 ppm
2017-07-03	325749001	0.673 ppm
2017-07-03	325747001	0.820 ppm
2017-07-03	325749001	0.890 ppm
2017-08-03	333403001	0.584 ppm
2017-08-03	333403001	0.585 ppm
2017-08-03	333404001	0.616 ppm
2017-08-03	333404001	0.639 ppm
2017-09-05	340665001	0.603 ppm
2017-09-05	340665001	0.615 ppm
2017-09-05	340666001	0.635 ppm
2017-09-05	340666001	0.642 ppm
2017-10-02	346760001	0.684 ppm
2017-10-02	346754001	0.732 ppm
2017-10-02	346760001	0.754 ppm
2017-10-02	346754001	0.789 ppm
2017-11-02	352274001	0.552 ppm
2017-11-02	352289001	0.653 ppm
2017-11-02	352274001	0.699 ppm
2017-11-02	352289001	0.751 ppm
2017-12-04	358084001	0.655 ppm
2017-12-04	358084001	0.733 ppm
2017-12-04	357941001	0.778 ppm
2017-12-04	357941001	0.780 ppm
2018-01-08	362346001	0.674 ppm
2018-01-08	362346001	0.748 ppm
2018-01-08	362362001	0.792 ppm
2018-01-08	362362001	0.793 ppm
2018-02-12	366980001	0.653 ppm
2018-02-12	366980001	0.768 ppm
2018-02-12	366976001	0.880 ppm
2018-02-12	366976001	0.916 ppm
2018-03-05	370121001	0.764 ppm
2018-03-05	370121001	0.803 ppm
2018-03-12	371406001	0.648 ppm
2018-03-12	371406001	0.696 ppm
2018-04-09	376291001	0.664 ppm
2018-04-09	376183001	0.783 ppm
2018-04-09	376183001	0.895 ppm
2018-04-09	376291001	0.911 ppm
2018-05-03	379933001	0.847 ppm
2018-05-03	379933001	0.847 ppm
2018-05-07	381008001	0.653 ppm
2018-05-07	381008001	0.694 ppm
2018-06-04	386974001	0.670 ppm
2018-06-04	386974001	0.703 ppm
2018-06-04	386980001	0.771 ppm
2018-06-04	386980001	0.778 ppm
2018-06-05	1060416	0.130 ppm
2018-07-05	392447001	0.681 ppm
2018-07-05	392447001	0.749 ppm
2018-07-09	393621001	0.657 ppm
2018-07-09	393621001	0.683 ppm
2018-08-06	399595001	0.748 ppm
2018-08-06	399589001	0.750 ppm
2018-08-06	399595001	0.754 ppm
2018-08-06	399589001	0.763 ppm
2018-09-04	405654001	0.776 ppm
2018-09-04	405654001	0.801 ppm
2018-09-04	405650001	0.942 ppm
2018-09-04	405650001	0.973 ppm
2018-10-04	413064001	0.661 ppm
2018-10-04	413064001	0.662 ppm
2018-10-04	413065001	0.731 ppm
2018-10-04	413065001	0.737 ppm
2018-11-05	418590001	0.634 ppm
2018-11-05	418590001	0.652 ppm
2018-11-05	418576001	0.735 ppm
2018-11-05	418576001	0.757 ppm
2018-12-03	422688001	0.678 ppm
2018-12-03	422688001	0.680 ppm
2018-12-03	422852001	0.786 ppm
2018-12-03	422852001	0.788 ppm
2019-01-07	427093001	0.649 ppm
2019-01-07	427093001	0.672 ppm
2019-01-07	427094001	0.726 ppm
2019-01-07	427094001	0.753 ppm
2019-02-04	430647001	0.662 ppm
2019-02-04	430647001	0.663 ppm
2019-02-04	430648001	0.711 ppm
2019-02-04	430648001	0.713 ppm
2019-03-04	434053001	0.666 ppm
2019-03-04	434053001	0.684 ppm
2019-03-04	434248001	0.718 ppm
2019-03-04	434248001	0.720 ppm
2019-04-08	439809001	0.633 ppm
2019-04-08	439809001	0.661 ppm
2019-04-08	439810001	0.705 ppm
2019-04-08	439810001	0.716 ppm
2019-05-06	445211001	0.660 ppm
2019-05-06	445211001	0.679 ppm
2019-05-07	445212001	0.680 ppm
2019-05-07	445212001	0.682 ppm
2019-06-03	450004001	0.649 ppm
2019-06-03	449997001	0.662 ppm
2019-06-03	449997001	0.679 ppm
2019-06-03	450004001	0.680 ppm
2019-07-08	456703001	0.582 ppm
2019-07-08	456703001	0.600 ppm
2019-07-08	456695001	0.619 ppm
2019-07-08	456695001	0.651 ppm
2019-08-05	462440001	0.592 ppm
2019-08-05	462455001	0.603 ppm
2019-08-05	462455001	0.679 ppm
2019-08-05	462440001	0.687 ppm
2019-09-09	469403001	0.654 ppm
2019-09-09	469403001	0.657 ppm
2019-09-09	469400001	0.736 ppm
2019-09-09	469400001	0.740 ppm
2019-09-10	1146567	0.130 ppm
2019-10-07	475745001	0.642 ppm
2019-10-07	475743001	0.647 ppm
2019-10-07	475745001	0.654 ppm
2019-10-07	475743001	0.675 ppm
2019-11-11	481540001	0.657 ppm
2019-11-11	481549001	0.668 ppm
2019-11-11	481549001	0.678 ppm
2019-11-11	481540001	0.678 ppm
2019-12-09	485986001	0.470 ppm
2019-12-09	485986001	0.543 ppm
2019-12-09	485700001	0.653 ppm
2019-12-09	485700001	0.670 ppm