Fluoride
City of Norfolk
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 |
|---|---|---|---|---|
| 2013 | N/A | 0 | 0 | N/A |
| 2014 | 0.665 ppm | 20 | 20 | 0.580 ppm - 0.820 ppm |
| 2015 | 0.602 ppm | 20 | 20 | 0.0800 ppm - 0.820 ppm |
| 2016 | 0.710 ppm | 20 | 20 | 0.590 ppm - 0.780 ppm |
| 2017 | 0.658 ppm | 19 | 19 | 0.550 ppm - 0.770 ppm |
| 2018 | 0.638 ppm | 8 | 8 | 0.170 ppm - 0.770 ppm |
| 2019 | 0.638 ppm | 8 | 8 | 0.600 ppm - 0.680 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 |
|---|---|---|
| 2014-01-08 | E120502575 | 0.820 ppm |
| 2014-02-05 | E120502576 | 0.590 ppm |
| 2014-02-11 | 14026243-INO | 0.640 ppm |
| 2014-02-11 | 14026242-INO | 0.710 ppm |
| 2014-03-10 | E120502578 | 0.600 ppm |
| 2014-04-13 | E120502579 | 0.650 ppm |
| 2014-05-12 | E120502580 | 0.730 ppm |
| 2014-05-13 | 14050227-INO | 0.630 ppm |
| 2014-05-13 | 14050226-INO | 0.750 ppm |
| 2014-06-15 | E120502581 | 0.640 ppm |
| 2014-07-21 | E120502582 | 0.640 ppm |
| 2014-08-12 | 14083425-INO | 0.650 ppm |
| 2014-08-12 | 14083424-INO | 0.620 ppm |
| 2014-08-14 | E140606925 | 0.630 ppm |
| 2014-09-21 | E140606922 | 0.580 ppm |
| 2014-10-14 | E140606927 | 0.690 ppm |
| 2014-11-12 | 14116687-INO | 0.790 ppm |
| 2014-11-12 | 14116688-INO | 0.630 ppm |
| 2014-11-14 | E140606924 | 0.700 ppm |
| 2014-12-15 | E140606926 | 0.600 ppm |
| 2015-01-14 | VA010-DCLS | 0.630 ppm |
| 2015-02-10 | 00225-CITY OF NO | 0.610 ppm |
| 2015-02-10 | 00225-CITY OF NO | 0.670 ppm |
| 2015-02-20 | VA010-DCLS | 0.650 ppm |
| 2015-03-16 | VA010-DCLS | 0.640 ppm |
| 2015-04-20 | VA010-DCLS | 0.560 ppm |
| 2015-05-12 | 00225-CITY OF NO | 0.660 ppm |
| 2015-05-12 | 00225-CITY OF NO | 0.600 ppm |
| 2015-05-20 | VA010-DCLS | 0.610 ppm |
| 2015-06-22 | VA010-DCLS | 0.690 ppm |
| 2015-07-21 | VA010-DCLS | 0.700 ppm |
| 2015-08-11 | 00225-CITY OF NO | 0.680 ppm |
| 2015-08-11 | 00225-CITY OF NO | 0.410 ppm |
| 2015-08-18 | VA010-DCLS | 0.700 ppm |
| 2015-09-24 | VA010-DCLS | 0.600 ppm |
| 2015-10-21 | VA010-DCLS | 0.540 ppm |
| 2015-11-09 | 00225-CITY OF NO | 0.600 ppm |
| 2015-11-09 | 00225-CITY OF NO | 0.0800 ppm |
| 2015-11-25 | VA010-DCLS | 0.590 ppm |
| 2015-12-23 | VA010-DCLS | 0.820 ppm |
| 2016-01-12 | E160101213 | 0.680 ppm |
| 2016-02-09 | 16022726-INO | 0.590 ppm |
| 2016-02-09 | 16022730-INO | 0.750 ppm |
| 2016-02-22 | E160101219 | 0.780 ppm |
| 2016-03-22 | E160101214 | 0.680 ppm |
| 2016-04-24 | E160101215 | 0.740 ppm |
| 2016-05-10 | 16055884-INO | 0.590 ppm |
| 2016-05-10 | 16055885-INO | 0.720 ppm |
| 2016-05-16 | E160101220 | 0.760 ppm |
| 2016-06-23 | E160101216 | 0.640 ppm |
| 2016-07-11 | E160101221 | 0.760 ppm |
| 2016-08-09 | 16089081-INO | 0.750 ppm |
| 2016-08-09 | 16089080-INO | 0.700 ppm |
| 2016-08-16 | E160101217 | 0.760 ppm |
| 2016-09-14 | E160101222 | 0.780 ppm |
| 2016-10-14 | E160101218 | 0.700 ppm |
| 2016-11-08 | 16112158-INO | 0.710 ppm |
| 2016-11-08 | 16112156-INO | 0.650 ppm |
| 2016-11-22 | E160101223 | 0.740 ppm |
| 2016-12-20 | E161102797 | 0.710 ppm |
| 2017-01-17 | E161102802 | 0.740 ppm |
| 2017-02-14 | 17025477-INO | 0.630 ppm |
| 2017-02-14 | 17025478-INO | 0.660 ppm |
| 2017-02-21 | E161102798 | 0.660 ppm |
| 2017-03-16 | E161102801 | 0.720 ppm |
| 2017-04-19 | E161102799 | 0.650 ppm |
| 2017-05-09 | 17058220-INO | 0.690 ppm |
| 2017-05-09 | 17058218-INO | 0.620 ppm |
| 2017-05-12 | E161102800 | 0.730 ppm |
| 2017-06-18 | E170600024 | 0.570 ppm |
| 2017-07-24 | E170600027 | 0.640 ppm |
| 2017-08-08 | 17081353-INO | 0.650 ppm |
| 2017-08-08 | 17081355-INO | 0.720 ppm |
| 2017-08-21 | E170600025 | 0.620 ppm |
| 2017-10-23 | E170600026 | 0.570 ppm |
| 2017-11-13 | E170600029 | 0.770 ppm |
| 2017-11-14 | 17114486-INO | 0.720 ppm |
| 2017-11-14 | 17114481-INO | 0.600 ppm |
| 2017-12-13 | E170906620 | 0.550 ppm |
| 2018-02-13 | 18027239-INO | 0.710 ppm |
| 2018-02-13 | 18027215-INO | 0.630 ppm |
| 2018-05-08 | 18059821-INO | 0.170 ppm |
| 2018-05-08 | 18059847-INO | 0.710 ppm |
| 2018-08-14 | 18083056-INO | 0.710 ppm |
| 2018-08-14 | 18083076-INO | 0.680 ppm |
| 2018-11-13 | 18115916-INO | 0.770 ppm |
| 2018-11-13 | 18115938-INO | 0.720 ppm |
| 2019-02-12 | 19028664-INO | 0.680 ppm |
| 2019-02-12 | 19028692-INO | 0.600 ppm |
| 2019-05-14 | 19052478-INO | 0.620 ppm |
| 2019-05-14 | 19052501-INO | 0.640 ppm |
| 2019-08-13 | 19085323-INO | 0.650 ppm |
| 2019-08-13 | 19085352-INO | 0.620 ppm |
| 2019-11-12 | 19118086-INO | 0.640 ppm |
| 2019-11-12 | 19118056-INO | 0.650 ppm |