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EWG's Tap Water Database — 2021 UPDATE

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Fluoride

Chaska

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.

 

30

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2013N/A00N/A
20140.623 ppm109ND - 1.50 ppm
20150.933 ppm440.610 ppm - 1.40 ppm
20160.628 ppm440.550 ppm - 0.730 ppm
20170.680 ppm440.600 ppm - 0.770 ppm
20180.590 ppm440.530 ppm - 0.630 ppm
20190.615 ppm440.590 ppm - 0.650 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
2014-02-0414B0177-020.290 ppm
2014-02-0414B0177-030.220 ppm
2014-02-0414B0177-04ND
2014-02-0414B0191-010.290 ppm
2014-02-0414B0191-020.290 ppm
2014-02-0414B0471-011.50 ppm
2014-02-0414B0177-010.240 ppm
2014-05-2014E2630-010.900 ppm
2014-08-1814H1909-011.20 ppm
2014-10-0614J0572-011.30 ppm
2015-01-2615A1216-011.10 ppm
2015-04-0115D0218-011.40 ppm
2015-07-3115H0119-010.620 ppm
2015-11-3015L0303-010.610 ppm
2016-02-0816B0576-010.580 ppm
2016-05-1116E0992-010.550 ppm
2016-08-0116H0323-010.730 ppm
2016-11-0116K0242-010.650 ppm
2017-02-1517B1017-010.770 ppm
2017-04-1817D1083-010.710 ppm
2017-08-2817H2261-010.600 ppm
2017-11-1417K0613-010.640 ppm
2018-02-0618B0422-010.580 ppm
2018-05-0918E0940-010.630 ppm
2018-08-0118H0150-010.620 ppm
2018-10-2418J1369-010.530 ppm
2019-02-1119B0437-010.650 ppm
2019-05-0619E0614-010.590 ppm
2019-07-2919G2172-010.600 ppm
2019-10-2219J1257-010.620 ppm