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EWG's Tap Water Database — 2021 UPDATE

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Fluoride

City of Davis

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.

 

81

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20140.168 ppm1816ND - 0.250 ppm
20150.185 ppm1614ND - 0.300 ppm
20160.226 ppm1614ND - 0.350 ppm
20170.173 ppm129ND - 0.410 ppm
20180.169 ppm119ND - 0.400 ppm
20190.186 ppm87ND - 0.340 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
2014-08-055810-052-0935ND
2014-08-055810-002-08220.200 ppm
2014-08-055810-004-08100.180 ppm
2014-08-055810-006-08370.240 ppm
2014-08-055810-009-11200.250 ppm
2014-08-055810-010-09180.170 ppm
2014-08-055810-014-09500.220 ppm
2014-08-055810-015-10360.200 ppm
2014-08-055810-016-08530.130 ppm
2014-08-055810-017-09090.160 ppm
2014-08-055810-018-07530.200 ppm
2014-08-055810-019-07370.200 ppm
2014-08-055810-020-06570.190 ppm
2014-08-055810-023-07200.180 ppm
2014-08-055810-024-10250.200 ppm
2014-08-055810-025-10000.170 ppm
2014-08-055810-026-1014ND
2014-08-055810-030-10590.130 ppm
2015-07-075810-004-12530.220 ppm
2015-07-075810-052-0648ND
2015-07-075810-030-09190.120 ppm
2015-07-075810-026-1041ND
2015-07-075810-025-08320.180 ppm
2015-07-075810-024-11200.220 ppm
2015-07-075810-023-09040.200 ppm
2015-07-075810-020-07570.210 ppm
2015-07-075810-002-13330.230 ppm
2015-07-075810-018-07210.220 ppm
2015-07-075810-006-11150.300 ppm
2015-07-075810-017-10300.180 ppm
2015-07-075810-010-11480.200 ppm
2015-07-075810-016-09570.180 ppm
2015-07-075810-015-13210.220 ppm
2015-07-215810-009-07470.280 ppm
2016-01-265810-019-10050.230 ppm
2016-07-135810-030-08440.150 ppm
2016-07-205810-026-0757ND
2016-07-205810-052-0843ND
2016-07-275810-015-09430.290 ppm
2016-07-275810-010-10210.280 ppm
2016-07-275810-016-08460.230 ppm
2016-07-275810-006-08170.350 ppm
2016-07-275810-017-10270.250 ppm
2016-07-275810-004-07500.260 ppm
2016-07-275810-018-08030.290 ppm
2016-07-275810-020-08360.270 ppm
2016-07-275810-019-09220.270 ppm
2016-07-275810-025-10090.220 ppm
2016-07-275810-024-09550.270 ppm
2016-07-275810-023-08550.260 ppm
2017-03-205810-057-1120ND
2017-06-145810-057-0820ND
2017-08-025810-052-1115ND
2017-08-025810-006-08590.320 ppm
2017-08-025810-019-08230.250 ppm
2017-08-025810-025-09250.410 ppm
2017-08-025810-018-08430.250 ppm
2017-08-025810-026-09430.120 ppm
2017-08-025810-020-08050.240 ppm
2017-08-035810-030-06250.160 ppm
2017-09-205810-057-09100.210 ppm
2017-12-125810-057-07350.110 ppm
2018-02-145810-057-0925ND
2018-04-185810-028-08550.130 ppm
2018-08-155810-019-09020.250 ppm
2018-08-155810-020-10010.250 ppm
2018-08-155810-018-08190.260 ppm
2018-08-155810-025-07550.400 ppm
2018-08-155810-057-08400.120 ppm
2018-08-155810-052-0930ND
2018-08-155810-028-07200.150 ppm
2018-08-155810-030-06400.140 ppm
2018-11-075810-028-08180.160 ppm
2019-08-079590-025-11020.340 ppm
2019-08-079590-028-10330.150 ppm
2019-08-079590-057-12000.120 ppm
2019-08-079590-052-1134ND
2019-08-079590-030-10080.130 ppm
2019-08-089590-018-10100.270 ppm
2019-08-089590-019-10330.250 ppm
2019-08-089590-020-11030.230 ppm