Fluoride
Chocorua Meadows
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.
Samples
Samples exceeding legal limit (MCL)
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2014 | 0.353 ppm | 23 | 12 | ND - 5.06 ppm |
| 2015 | 4.94 ppm | 1 | 1 | 4.94 ppm |
| 2016 | 0.825 ppm | 23 | 21 | ND - 5.20 ppm |
| 2017 | 0.664 ppm | 22 | 20 | ND - 5.75 ppm |
| 2018 | 0.777 ppm | 22 | 21 | ND - 5.25 ppm |
| 2019 | 1.72 ppm | 21 | 18 | ND - 25.0 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 |
|---|---|---|
| 2014-06-08 | A403386001 | 0.200 ppm |
| 2014-08-18 | 218740 | 5.06 ppm |
| 2014-12-13 | A409746003 | ND |
| 2014-12-13 | A409746014 | ND |
| 2014-12-14 | A409746005 | ND |
| 2014-12-14 | A409746006 | ND |
| 2014-12-14 | A409746009 | 0.260 ppm |
| 2014-12-14 | A409746011 | ND |
| 2014-12-14 | A409746012 | ND |
| 2014-12-14 | A409746013 | 0.310 ppm |
| 2014-12-14 | A409746015 | 0.240 ppm |
| 2014-12-14 | A409746016 | ND |
| 2014-12-14 | A409746017 | 0.340 ppm |
| 2014-12-14 | A409746018 | 0.220 ppm |
| 2014-12-14 | A409746020 | 0.210 ppm |
| 2014-12-14 | A409746021 | 0.210 ppm |
| 2014-12-15 | A409746001 | 0.540 ppm |
| 2014-12-15 | A409746002 | 0.320 ppm |
| 2014-12-15 | A409746004 | ND |
| 2014-12-15 | A409746007 | ND |
| 2014-12-15 | A409746008 | ND |
| 2014-12-15 | A409746010 | 0.210 ppm |
| 2014-12-15 | A409746019 | ND |
| 2015-08-04 | 215080146.01 | 4.94 ppm |
| 2016-08-23 | 216080998 | 4.14 ppm |
| 2016-12-04 | B610684001 | 0.580 ppm |
| 2016-12-04 | B610684002 | 0.600 ppm |
| 2016-12-04 | B610684003 | 0.400 ppm |
| 2016-12-04 | B610684004 | 0.450 ppm |
| 2016-12-04 | B610684005 | 0.210 ppm |
| 2016-12-04 | B610684006 | 0.330 ppm |
| 2016-12-04 | B610684007 | 0.410 ppm |
| 2016-12-04 | B610684008 | 0.860 ppm |
| 2016-12-04 | B610684009 | 0.530 ppm |
| 2016-12-04 | B610684010 | 5.20 ppm |
| 2016-12-04 | B610684011 | 0.410 ppm |
| 2016-12-04 | B610684012 | 0.420 ppm |
| 2016-12-04 | B610684014 | ND |
| 2016-12-04 | B610684015 | 0.530 ppm |
| 2016-12-04 | B610684016 | ND |
| 2016-12-04 | B610684017 | 0.580 ppm |
| 2016-12-04 | B610684019 | 0.400 ppm |
| 2016-12-04 | B610684020 | 0.670 ppm |
| 2016-12-04 | B610684021 | 0.370 ppm |
| 2016-12-05 | B610684013 | 0.500 ppm |
| 2016-12-05 | B610684018 | 1.000 ppm |
| 2016-12-28 | 1612-02079-001 | 0.378 ppm |
| 2017-07-19 | 217070700 | 5.75 ppm |
| 2017-12-03 | B710269007 | 0.370 ppm |
| 2017-12-03 | B710269008 | 0.540 ppm |
| 2017-12-03 | B710269009 | 0.380 ppm |
| 2017-12-03 | B710269010 | 0.240 ppm |
| 2017-12-03 | B710269011 | 0.430 ppm |
| 2017-12-03 | B710269012 | 0.330 ppm |
| 2017-12-03 | B710269013 | 0.410 ppm |
| 2017-12-03 | B710269014 | ND |
| 2017-12-03 | B710269015 | 0.500 ppm |
| 2017-12-03 | B710269016 | ND |
| 2017-12-03 | B710269017 | 1.000 ppm |
| 2017-12-03 | B710269018 | 0.830 ppm |
| 2017-12-03 | B710269019 | 0.530 ppm |
| 2017-12-03 | B710269020 | 0.490 ppm |
| 2017-12-04 | B710269001 | 0.340 ppm |
| 2017-12-04 | B710269002 | 0.680 ppm |
| 2017-12-04 | B710269003 | 0.200 ppm |
| 2017-12-04 | B710269004 | 0.380 ppm |
| 2017-12-04 | B710269005 | 0.590 ppm |
| 2017-12-04 | B710269006 | 0.310 ppm |
| 2017-12-04 | B710269021 | 0.300 ppm |
| 2018-08-14 | 218080640.01 | 5.25 ppm |
| 2018-12-08 | B810042002 | 0.590 ppm |
| 2018-12-08 | B810042003 | 0.270 ppm |
| 2018-12-08 | B810042004 | 0.520 ppm |
| 2018-12-08 | B810042006 | 0.280 ppm |
| 2018-12-08 | B810042009 | 0.230 ppm |
| 2018-12-08 | B810042010 | 0.260 ppm |
| 2018-12-08 | B810042011 | 0.660 ppm |
| 2018-12-08 | B810042012 | 0.440 ppm |
| 2018-12-08 | B810042013 | 0.720 ppm |
| 2018-12-08 | B810042014 | ND |
| 2018-12-08 | B810042015 | 0.350 ppm |
| 2018-12-08 | B810042016 | 2.50 ppm |
| 2018-12-08 | B810042017 | 0.730 ppm |
| 2018-12-08 | B810042018 | 0.720 ppm |
| 2018-12-08 | B810042020 | 0.460 ppm |
| 2018-12-09 | B810042001 | 0.340 ppm |
| 2018-12-09 | B810042005 | 0.600 ppm |
| 2018-12-09 | B810042007 | 0.870 ppm |
| 2018-12-09 | B810042008 | 0.450 ppm |
| 2018-12-09 | B810042019 | 0.590 ppm |
| 2018-12-09 | B810042021 | 0.270 ppm |
| 2019-12-15 | B910771001 | 0.510 ppm |
| 2019-12-15 | B910771002 | 1.30 ppm |
| 2019-12-15 | B910771003 | 0.590 ppm |
| 2019-12-15 | B910771010 | 0.350 ppm |
| 2019-12-15 | B910771011 | 0.730 ppm |
| 2019-12-15 | B910771012 | 0.400 ppm |
| 2019-12-15 | B910771013 | 1.60 ppm |
| 2019-12-15 | B910771014 | ND |
| 2019-12-15 | B910771015 | 0.440 ppm |
| 2019-12-15 | B910771016 | 25.0 ppm |
| 2019-12-15 | B910771017 | 0.860 ppm |
| 2019-12-15 | B910771018 | 0.950 ppm |
| 2019-12-15 | B910771019 | 0.520 ppm |
| 2019-12-16 | B910771004 | ND |
| 2019-12-16 | B910771005 | ND |
| 2019-12-16 | B910771006 | 0.300 ppm |
| 2019-12-16 | B910771007 | 0.700 ppm |
| 2019-12-16 | B910771008 | 0.570 ppm |
| 2019-12-16 | B910771009 | 0.360 ppm |
| 2019-12-16 | B910771020 | 0.510 ppm |
| 2019-12-16 | B910771021 | 0.360 ppm |