Know Your Environment. Protect Your Health.

Fluoride

Clarendon Waterworks

Fluoride occurs naturally in surface and groundwater and is also added to drinking water by many water systems to prevent cavities and support oral health in people.

In 2015, the Department of Health and Human Services updated its recommendation of an optimal level of 0.7 parts per million, or ppm, added to drinking water based on the health benefits of tooth decay prevention. Studies have shown that fluoride added to community water systems at this level reduces dental cavities, especially in children.

And studies have conclusively shown that fluoride in toothpaste and mouthwash can also provide these benefits. Read More.

Health Concerns

Although the HHS-recommended level of 0.7 ppm can help promote oral health in children and adults, this level is likely too high for bottle-fed babies. EWG recommends that caregivers mix baby formula with fluoride-free water.

And fluoride in water at higher levels can be detrimental for everyone, especially children.

Long-term ingestion of higher levels of fluoride in water increases dental fluorosis, which includes mottling, pitting and weakening of the teeth in children.

A 2024 authoritative assessment by the National Toxicology Program found that higher levels of fluoride exposure, such as drinking water containing more than 1.5 ppm of fluoride, are associated with lower IQ in children. The conclusion was based on studies in human populations outside of the U.S.

Affecting systems with naturally occurring fluoride, 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 fracture. But these effects may occur at lower levels of exposure, raising concerns that the current limit may not adequately protect public health.

 

72

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.717 ppm11110.460 ppm - 1.18 ppm
20190.922 ppm12120.740 ppm - 1.36 ppm
20200.718 ppm13130.220 ppm - 1.06 ppm
20210.573 ppm1211ND - 0.850 ppm
2022ND120ND
20230.146 ppm1210ND - 0.190 ppm

ppm = parts per million

State, National, and Health Guidelines for Drinking Water

EPA Maximum Contaminant
Level (MCL): 4 ppm

ppm = parts per million

All test results

Date Lab ID Result
2018-01-23Y1802400210.670 ppm
2018-02-20Y1805300300.740 ppm
2018-03-26Y1809200040.750 ppm
2018-04-26Y1812200090.650 ppm
2018-05-24Y1814900220.460 ppm
2018-06-28Y1818300250.640 ppm
2018-08-02Y1821900140.590 ppm
2018-09-06Y1825300360.850 ppm
2018-10-30Y1830900190.640 ppm
2018-11-29Y1833700271.18 ppm
2018-12-27Y1836500030.720 ppm
2019-01-31Y1903500250.980 ppm
2019-02-20Y1905600360.830 ppm
2019-03-11Y1907700071.36 ppm
2019-04-15Y1911200080.740 ppm
2019-05-20Y1915300190.970 ppm
2019-06-10Y1916800020.940 ppm
2019-07-08Y1919600500.860 ppm
2019-08-20Y1923800230.890 ppm
2019-09-11Y1925900170.930 ppm
2019-10-22Y1930100100.910 ppm
2019-11-14Y1932900380.840 ppm
2019-12-09Y1934700410.810 ppm
2020-01-22Y2002700060.890 ppm
2020-02-10Y2004900111.06 ppm
2020-03-09Y2007700210.220 ppm
2020-04-21Y2012000250.800 ppm
2020-05-18Y2015400510.760 ppm
2020-06-22Y2017500030.620 ppm
2020-06-23Y2017700270.620 ppm
2020-07-27Y2021000030.580 ppm
2020-08-17Y2023100370.450 ppm
2020-09-28Y2027400020.700 ppm
2020-10-21Y2029600020.740 ppm
2020-11-24Y2033000090.970 ppm
2020-12-14Y2035000030.920 ppm
2021-01-20Y2102200170.800 ppm
2021-02-25Y2105700050.670 ppm
2021-03-10Y2107100040.620 ppm
2021-04-26Y2111700040.610 ppm
2021-05-24Y2114500010.850 ppm
2021-06-28Y2118000060.790 ppm
2021-07-21Y2120300050.780 ppm
2021-08-25Y2123800010.690 ppm
2021-09-22Y2126600110.520 ppm
2021-10-27Y2130100540.320 ppm
2021-11-23Y2132800030.230 ppm
2021-12-15Y213500001ND
2022-01-24Y220250001ND
2022-02-23Y220560023ND
2022-03-24Y220840001ND
2022-04-28Y221220001ND
2022-05-18Y221390009ND
2022-06-23Y221750002ND
2022-07-20Y222020042ND
2022-08-23Y222360001ND
2022-09-20Y222690006ND
2022-10-19Y222930057ND
2022-11-21Y223260020ND
2022-12-28Y223630002ND
2023-01-25Y230260004ND
2023-02-23Y230550012ND
2023-03-21Y2308200020.180 ppm
2023-04-10Y2310300120.180 ppm
2023-04-10Y2310100060.190 ppm
2023-06-26Y2317800030.170 ppm
2023-07-25Y2320700030.160 ppm
2023-08-17Y2323000010.170 ppm
2023-09-25Y2326900010.170 ppm
2023-10-25Y2329800040.170 ppm
2023-11-27Y2333200030.180 ppm
2023-12-18Y2335300060.180 ppm