Fluoride
Commerce-city, Water Department
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 | 0.377 ppm | 11 | 11 | 0.289 ppm - 0.772 ppm |
| 2015 | 0.303 ppm | 14 | 14 | 0.270 ppm - 0.327 ppm |
| 2016 | 0.310 ppm | 12 | 12 | 0.301 ppm - 0.321 ppm |
| 2017 | 0.451 ppm | 12 | 12 | 0.297 ppm - 0.776 ppm |
| 2018 | 0.386 ppm | 14 | 14 | 0.304 ppm - 0.779 ppm |
| 2019 | 0.416 ppm | 12 | 12 | 0.302 ppm - 0.712 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 |
|---|---|---|
| 2014-01-07 | 5701-800-1106 | 0.316 ppm |
| 2014-02-04 | 5701-801-1000 | 0.290 ppm |
| 2014-03-04 | 5701-800-0911 | 0.295 ppm |
| 2014-05-06 | 5701-800-0957 | 0.772 ppm |
| 2014-06-02 | 5701-801-1047 | 0.299 ppm |
| 2014-07-01 | 5701-800-0844 | 0.368 ppm |
| 2014-08-05 | 5701-801-1432 | 0.308 ppm |
| 2014-09-03 | 5701-800-0925 | 0.573 ppm |
| 2014-10-01 | 5701-801-0840 | 0.308 ppm |
| 2014-11-04 | 5701-800-0908 | 0.289 ppm |
| 2014-12-09 | 5701-801-0920 | 0.325 ppm |
| 2015-01-06 | 5701-800-0901 | 0.307 ppm |
| 2015-02-03 | 5701-801-0950 | 0.300 ppm |
| 2015-03-03 | 5701-800-0924 | 0.299 ppm |
| 2015-04-01 | 5701-801-1445 | 0.304 ppm |
| 2015-05-05 | 5701-800-0852 | 0.304 ppm |
| 2015-05-12 | 5810-005-1221 | 0.270 ppm |
| 2015-06-02 | 5810-008-1240 | 0.280 ppm |
| 2015-06-09 | 5701-801-1227 | 0.307 ppm |
| 2015-07-07 | 5701-800-1554 | 0.305 ppm |
| 2015-08-04 | 5701-801-1343 | 0.300 ppm |
| 2015-09-01 | 5701-800-0858 | 0.306 ppm |
| 2015-10-10 | 5701-801-1104 | 0.307 ppm |
| 2015-11-03 | 5701-800-1011 | 0.319 ppm |
| 2015-12-08 | 5701-801-0922 | 0.327 ppm |
| 2016-01-11 | 5701-800-1047 | 0.321 ppm |
| 2016-02-02 | 5701-801-0935 | 0.304 ppm |
| 2016-03-08 | 5701-800-1013 | 0.304 ppm |
| 2016-04-04 | 5701-801-1134 | 0.304 ppm |
| 2016-05-03 | 5701-800-0927 | 0.316 ppm |
| 2016-06-06 | 5701-801-1017 | 0.301 ppm |
| 2016-07-12 | 5701-800-0944 | 0.311 ppm |
| 2016-08-02 | 5701-801-0856 | 0.315 ppm |
| 2016-09-12 | 5701-800-1031 | 0.303 ppm |
| 2016-10-04 | 5701-801-0901 | 0.311 ppm |
| 2016-11-01 | 5701-800-0958 | 0.313 ppm |
| 2016-12-06 | 5701-801-0945 | 0.311 ppm |
| 2017-01-10 | 5701-800-1356 | 0.334 ppm |
| 2017-02-07 | 5701-801-0945 | 0.324 ppm |
| 2017-03-06 | 5701-800-1002 | 0.324 ppm |
| 2017-04-11 | 5701-801-0917 | 0.307 ppm |
| 2017-05-09 | 5701-800-0926 | 0.297 ppm |
| 2017-06-05 | 5701-801-0954 | 0.679 ppm |
| 2017-07-11 | 5701-800-0957 | 0.397 ppm |
| 2017-08-08 | 5701-801-0847 | 0.776 ppm |
| 2017-09-12 | 5701-800-1018 | 0.763 ppm |
| 2017-10-10 | 5701-801-1012 | 0.568 ppm |
| 2017-11-07 | 5701-800-0923 | 0.338 ppm |
| 2017-12-05 | 5701-801-0943 | 0.304 ppm |
| 2018-01-09 | 5701-800-1958 | 0.311 ppm |
| 2018-02-06 | 5701-801-0910 | 0.305 ppm |
| 2018-03-06 | 5701-800-0929 | 0.324 ppm |
| 2018-04-03 | 5701-801-1059 | 0.304 ppm |
| 2018-05-01 | 5701-800-1041 | 0.344 ppm |
| 2018-05-15 | 5810-005-1041 | 0.320 ppm |
| 2018-06-12 | 5701-801-0910 | 0.779 ppm |
| 2018-06-13 | 5810-008-1426 | 0.320 ppm |
| 2018-07-10 | 5701-800-1002 | 0.311 ppm |
| 2018-08-07 | 5701-801-1500 | 0.332 ppm |
| 2018-09-11 | 5701-800-1028 | 0.359 ppm |
| 2018-10-02 | 5701-801-1422 | 0.654 ppm |
| 2018-11-13 | 5701-800-0927 | 0.418 ppm |
| 2018-12-04 | 5701-801-0935 | 0.320 ppm |
| 2019-01-08 | 5701-800-1107 | 0.352 ppm |
| 2019-02-12 | 5701-801-0949 | 0.303 ppm |
| 2019-03-12 | 5701-800-1029 | 0.325 ppm |
| 2019-04-09 | 5810-801-0911 | 0.660 ppm |
| 2019-05-07 | 5701-800-1010 | 0.309 ppm |
| 2019-06-04 | 5701-801-1132 | 0.331 ppm |
| 2019-07-08 | 5701-800-0940 | 0.307 ppm |
| 2019-08-06 | 5701-801-0930 | 0.712 ppm |
| 2019-09-04 | 5701-800-0932 | 0.406 ppm |
| 2019-10-08 | 5701-801-0938 | 0.665 ppm |
| 2019-11-12 | 5701-800-0938 | 0.323 ppm |
| 2019-12-03 | 5701-801-1007 | 0.302 ppm |