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EWG's Tap Water Database — 2021 UPDATE

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Fluoride

City of Winston-Salem

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.

MORE ABOUT THIS CONTAMINANT

 

216

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20140.577 ppm330.540 ppm - 0.630 ppm
20150.447 ppm32ND - 0.720 ppm
20160.298 ppm6334ND - 0.770 ppm
20170.323 ppm6638ND - 0.850 ppm
20180.686 ppm36360.530 ppm - 1.25 ppm
20190.696 ppm45450.520 ppm - 0.870 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
2014-12-01AA502620.560 ppm
2014-12-01AA502630.630 ppm
2014-12-01AA502640.540 ppm
2015-12-07ND
2015-12-070.720 ppm
2015-12-070.620 ppm
2016-08-088881-080816-EP1I0.660 ppm
2016-08-088881-080816-EP2I0.770 ppm
2016-08-088881-080816-EP3I0.580 ppm
2016-08-158881-081516-EP1I0.540 ppm
2016-08-158881-081516-EP2I0.620 ppm
2016-08-158881-081516-EP3I0.540 ppm
2016-08-228881-082216-EP1I0.550 ppm
2016-08-228881-082216-EP2I0.670 ppm
2016-08-228881-082216-EP3I0.530 ppm
2016-08-298881-082916-EP1I0.530 ppm
2016-08-298881-082916-EP2I0.640 ppm
2016-08-298881-082916-EP3I0.470 ppm
2016-09-058881-090516-EP1I0.590 ppm
2016-09-058881-090516-EP2IND
2016-09-058881-090516-EP3I0.480 ppm
2016-09-128881-091216-EP1I0.470 ppm
2016-09-128881-091216-EP2IND
2016-09-128881-091216-EP3I0.440 ppm
2016-09-198881-091916-EP1I0.590 ppm
2016-09-198881-091916-EP2IND
2016-09-198881-091916-EP3I0.600 ppm
2016-09-268881-092616-EP1I0.540 ppm
2016-09-268881-092616-EP2IND
2016-09-268881-092616-EP3IND
2016-10-038881-100316-EP1I0.430 ppm
2016-10-038881-100316-EP2IND
2016-10-038881-100316-EP3IND
2016-10-108881-101016-EP1I0.550 ppm
2016-10-108881-101016-EP2IND
2016-10-108881-101016-EP3IND
2016-10-178881-101716-EP1I0.520 ppm
2016-10-178881-101716-EP2IND
2016-10-178881-101716-EP3IND
2016-10-248881-102416-EP1I0.510 ppm
2016-10-248881-102416-EP2IND
2016-10-248881-102416-EP3IND
2016-10-318881-103116-EP1I0.590 ppm
2016-10-318881-103116-EP2IND
2016-10-318881-103116-EP3IND
2016-11-078881-110716-EP1I0.560 ppm
2016-11-078881-110716-EP2I0.440 ppm
2016-11-078881-110716-EP3I0.340 ppm
2016-11-148881-111416-EP1I0.580 ppm
2016-11-148881-111416-EP2IND
2016-11-148881-111416-EP3IND
2016-11-218881-112116-EP1I0.550 ppm
2016-11-218881-112116-EP2IND
2016-11-218881-112116-EP3IND
2016-11-288881-112816-EP1I0.550 ppm
2016-11-288881-112816-EP2IND
2016-11-288881-112816-EP3IND
2016-12-058881-120516-EP1I0.630 ppm
2016-12-058881-120516-EP2IND
2016-12-058881-120516-EP3IND
2016-12-128881-121216-EP1I0.530 ppm
2016-12-128881-121216-EP2IND
2016-12-128881-121216-EP3IND
2016-12-198881-121916-EP1I0.530 ppm
2016-12-198881-121916-EP2IND
2016-12-198881-121916-EP3IND
2016-12-268881-122616-EP1I0.650 ppm
2016-12-268881-122616-EP2IND
2016-12-268881-122616-EP3IND
2017-01-038881-010317-EP1I0.580 ppm
2017-01-038881-010317-EP2IND
2017-01-038881-010317-EP3IND
2017-01-108881-011017-EP2IND
2017-01-108881-011017-EP3IND
2017-01-108881-011017-EP1I0.430 ppm
2017-01-178881-011717-EP1I0.530 ppm
2017-01-178881-011717-EP2IND
2017-01-178881-011717-EP3IND
2017-01-238881-012317-EP1I0.630 ppm
2017-01-238881-012317-EP2IND
2017-01-238881-012317-EP3IND
2017-01-308881-013017-EP1I0.630 ppm
2017-01-308881-013017-EP2I0.360 ppm
2017-01-308881-013017-EP3IND
2017-02-068881-020617-EP1I0.610 ppm
2017-02-068881-020617-EP2I0.1000 ppm
2017-02-068881-020617-EP3IND
2017-02-138881-021317-EP1I0.600 ppm
2017-02-138881-021317-EP2IND
2017-02-138881-021317-EP3IND
2017-02-208881-022017-EP1I0.620 ppm
2017-02-208881-022017-EP2IND
2017-02-208881-022017-EP3IND
2017-02-278881-022717-EP1I0.540 ppm
2017-02-278881-022717-EP2IND
2017-02-278881-022717-EP3IND
2017-03-068881-030617-EP1I0.650 ppm
2017-03-068881-030617-EP2IND
2017-03-068881-030617-EP3IND
2017-03-138881-031317-EP1I0.520 ppm
2017-03-138881-031317-EP2IND
2017-03-138881-031317-EP3IND
2017-03-208881-032017-EP1I0.490 ppm
2017-03-208881-032017-EP2IND
2017-03-208881-032017-EP3IND
2017-03-278881-032717-EP1I0.580 ppm
2017-03-278881-032717-EP2IND
2017-03-278881-032717-EP3IND
2017-04-038881-040317-EP1I0.590 ppm
2017-04-038881-040317-EP2IND
2017-04-038881-040317-EP3IND
2017-05-018881-050117-EP1I0.530 ppm
2017-05-018881-050117-EP2IND
2017-05-018881-050117-EP3IND
2017-06-128881-061217-EP1I0.540 ppm
2017-06-128881-061217-EP2I0.520 ppm
2017-06-128881-061217-EP3I0.570 ppm
2017-07-108881-071017-EP1I0.660 ppm
2017-07-108881-071017-EP2I0.580 ppm
2017-07-108881-071017-EP3I0.560 ppm
2017-08-078881-080717-EP1I0.620 ppm
2017-08-078881-080717-EP2I0.600 ppm
2017-08-078881-080717-EP3I0.680 ppm
2017-09-058881-090517-EP1I0.650 ppm
2017-09-058881-090517-EP2I0.630 ppm
2017-09-058881-090517-EP3I0.650 ppm
2017-10-028881-100217-EP1I0.440 ppm
2017-10-028881-100217-EP2I0.460 ppm
2017-10-028881-100217-EP3I0.590 ppm
2017-11-138881-111317-EP1I0.540 ppm
2017-11-138881-111317-EP2I0.520 ppm
2017-11-138881-111317-EP3I0.470 ppm
2017-12-118881-121117-EP1I0.630 ppm
2017-12-118881-121117-EP2I0.580 ppm
2017-12-118881-121117-EP3I0.850 ppm
2018-01-228881-012218-EP1I0.970 ppm
2018-01-228881-012218-EP2I1.25 ppm
2018-01-228881-012218-EP3I0.890 ppm
2018-02-198881-021918-EP1I0.580 ppm
2018-02-198881-021918-EP2I0.590 ppm
2018-02-198881-021918-EP3I0.790 ppm
2018-03-058881-030518-EP1I0.530 ppm
2018-03-058881-030518-EP2I0.620 ppm
2018-03-058881-030518-EP3I0.730 ppm
2018-04-168881-041618-EP1I0.580 ppm
2018-04-168881-041618-EP2I0.620 ppm
2018-04-168881-041618-EP3I0.740 ppm
2018-05-078881-050718-EP1I0.610 ppm
2018-05-078881-050718-EP2I0.620 ppm
2018-05-078881-050718-EP3I0.720 ppm
2018-06-048881-060418-EP1I0.620 ppm
2018-06-048881-060418-EP2I0.640 ppm
2018-06-048881-060418-EP3I0.780 ppm
2018-07-168881-071618-EP1I0.600 ppm
2018-07-168881-071618-EP2I0.570 ppm
2018-07-168881-071618-EP3I0.800 ppm
2018-08-068881-080618-EP1I0.580 ppm
2018-08-068881-080618-EP2I0.570 ppm
2018-08-068881-080618-EP3I0.760 ppm
2018-09-248881-092418-EP1I0.610 ppm
2018-09-248881-092418-EP2I0.620 ppm
2018-09-248881-092418-EP3I0.760 ppm
2018-10-08AA66365 0.623 ppm
2018-10-08AA66366 0.685 ppm
2018-10-08AA66367 0.814 ppm
2018-11-198881-111918-EP1I0.640 ppm
2018-11-198881-111918-EP2I0.650 ppm
2018-11-198881-111918-EP3I0.670 ppm
2018-12-118881_121118_EP1I0.560 ppm
2018-12-118881_121118_EP2I0.600 ppm
2018-12-118881_121118_EP3I0.690 ppm
2019-01-14AA67248 0.678 ppm
2019-01-14AA67249 0.643 ppm
2019-01-14AA67250 0.696 ppm
2019-01-228881-012219-EP1I0.520 ppm
2019-01-228881-012219-EP2I0.540 ppm
2019-01-228881-012219-EP3I0.560 ppm
2019-02-048881-020419-EP1I0.560 ppm
2019-02-048881-020419-EP2I0.600 ppm
2019-02-048881-020419-EP3I0.630 ppm
2019-03-048881-030419-EP1I0.670 ppm
2019-03-048881-030419-EP2I0.690 ppm
2019-03-048881-030419-EP3I0.740 ppm
2019-04-018881-040119-EP1I0.620 ppm
2019-04-018881-040119-EP2I0.740 ppm
2019-04-018881-040119-EP3I0.610 ppm
2019-05-068881-050619-EP1I0.610 ppm
2019-05-068881-050619-EP2I0.680 ppm
2019-05-068881-050619-EP3I0.670 ppm
2019-06-038881-060319-EP1I0.660 ppm
2019-06-038881-060319-EP2I0.790 ppm
2019-06-038881-060319-EP3I0.790 ppm
2019-07-018881-070119-EP1I0.610 ppm
2019-07-018881-070119-EP2I0.710 ppm
2019-07-018881-070119-EP3I0.760 ppm
2019-07-01AA68890 0.642 ppm
2019-07-01AA68891 0.726 ppm
2019-07-01AA68892 0.762 ppm
2019-08-058881-080519-EP1I0.810 ppm
2019-08-058881-080519-EP2I0.660 ppm
2019-08-058881-080519-EP3I0.840 ppm
2019-08-05AA69258 0.827 ppm
2019-08-05AA69259 0.696 ppm
2019-08-05AA69260 0.865 ppm
2019-09-038881-090319-EP1I0.750 ppm
2019-09-038881-090319-EP2I0.730 ppm
2019-09-038881-090319-EP3I0.870 ppm
2019-10-078881-100719-EP1I0.750 ppm
2019-10-078881-100719-EP2I0.680 ppm
2019-10-078881-100719-EP3I0.800 ppm
2019-11-048881-110419-EP1I0.780 ppm
2019-11-048881-110419-EP2I0.600 ppm
2019-11-048881-110419-EP3I0.770 ppm
2019-12-028881-120219-EP1I0.760 ppm
2019-12-028881-120219-EP2I0.520 ppm
2019-12-028881-120219-EP3I0.700 ppm