Fluoride
Ashland Water Utility
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 | 0.622 ppm | 25 | 25 | 0.508 ppm - 0.810 ppm |
| 2015 | 0.646 ppm | 25 | 25 | 0.539 ppm - 0.870 ppm |
| 2016 | 0.648 ppm | 25 | 25 | 0.530 ppm - 0.970 ppm |
| 2017 | 0.642 ppm | 25 | 25 | 0.567 ppm - 0.740 ppm |
| 2018 | 0.636 ppm | 25 | 25 | 0.490 ppm - 0.720 ppm |
| 2019 | 0.632 ppm | 25 | 25 | 0.180 ppm - 0.770 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 | 116560001 | 0.529 ppm |
| 2014-01-08 | 116560001 | 0.710 ppm |
| 2014-02-06 | 118901001 | 0.508 ppm |
| 2014-02-06 | 118901001 | 0.700 ppm |
| 2014-03-18 | 124432001 | 0.520 ppm |
| 2014-03-18 | 124432001 | 0.740 ppm |
| 2014-04-01 | 126117001 | 0.509 ppm |
| 2014-04-01 | 126117001 | 0.680 ppm |
| 2014-05-08 | 131645001 | 0.536 ppm |
| 2014-05-08 | 131645001 | 0.610 ppm |
| 2014-06-11 | 139053001 | 0.603 ppm |
| 2014-06-11 | 139053001 | 0.700 ppm |
| 2014-07-03 | 144474001 | 0.606 ppm |
| 2014-07-03 | 144474001 | 0.650 ppm |
| 2014-08-13 | 810306 | 0.530 ppm |
| 2014-08-13 | 151675001 | 0.642 ppm |
| 2014-08-13 | 151675001 | 0.660 ppm |
| 2014-09-04 | 155231001 | 0.592 ppm |
| 2014-09-04 | 155231001 | 0.660 ppm |
| 2014-10-01 | 161476001 | 0.653 ppm |
| 2014-10-01 | 161476001 | 0.810 ppm |
| 2014-11-06 | 167612001 | 0.566 ppm |
| 2014-11-06 | 167612001 | 0.600 ppm |
| 2014-12-02 | 171256001 | 0.568 ppm |
| 2014-12-02 | 171256001 | 0.680 ppm |
| 2015-01-08 | 175009001 | 0.539 ppm |
| 2015-01-08 | 175009001 | 0.667 ppm |
| 2015-02-05 | 178933001 | 0.548 ppm |
| 2015-02-05 | 178933001 | 0.678 ppm |
| 2015-03-04 | 182277001 | 0.610 ppm |
| 2015-03-04 | 182277001 | 0.638 ppm |
| 2015-03-10 | 847367 | 0.800 ppm |
| 2015-04-01 | 185952001 | 0.608 ppm |
| 2015-04-01 | 185952001 | 0.678 ppm |
| 2015-05-06 | 192227001 | 0.584 ppm |
| 2015-05-06 | 192227001 | 0.600 ppm |
| 2015-06-02 | 197734001 | 0.613 ppm |
| 2015-06-02 | 197734001 | 0.730 ppm |
| 2015-07-07 | 204806001 | 0.592 ppm |
| 2015-07-07 | 204806001 | 0.693 ppm |
| 2015-08-05 | 210423001 | 0.628 ppm |
| 2015-08-05 | 210423001 | 0.730 ppm |
| 2015-09-02 | 215677001 | 0.617 ppm |
| 2015-09-02 | 215677001 | 0.663 ppm |
| 2015-10-07 | 223295001 | 0.600 ppm |
| 2015-10-07 | 223295001 | 0.650 ppm |
| 2015-11-02 | 227369001 | 0.561 ppm |
| 2015-11-02 | 227369001 | 0.628 ppm |
| 2015-12-01 | 232234001 | 0.620 ppm |
| 2015-12-01 | 232234001 | 0.870 ppm |
| 2016-01-05 | 235060001 | 0.620 ppm |
| 2016-01-05 | 235060001 | 0.660 ppm |
| 2016-01-18 | 901705 | 0.970 ppm |
| 2016-02-03 | 238405001 | 0.634 ppm |
| 2016-02-03 | 238405001 | 0.650 ppm |
| 2016-03-02 | 242279001 | 0.640 ppm |
| 2016-03-02 | 242279001 | 0.667 ppm |
| 2016-04-04 | 247510001 | 0.597 ppm |
| 2016-04-04 | 247510001 | 0.640 ppm |
| 2016-05-03 | 252825001 | 0.604 ppm |
| 2016-05-03 | 252825001 | 0.661 ppm |
| 2016-06-06 | 259526001 | 0.623 ppm |
| 2016-06-06 | 259526001 | 0.640 ppm |
| 2016-07-06 | 264906001 | 0.530 ppm |
| 2016-07-06 | 264906001 | 0.626 ppm |
| 2016-08-02 | 270500001 | 0.637 ppm |
| 2016-08-02 | 270500001 | 0.690 ppm |
| 2016-09-07 | 276523001 | 0.580 ppm |
| 2016-09-07 | 276523001 | 0.617 ppm |
| 2016-10-10 | 283985001 | 0.627 ppm |
| 2016-10-10 | 283985001 | 0.660 ppm |
| 2016-11-08 | 289646001 | 0.666 ppm |
| 2016-11-08 | 289646001 | 0.698 ppm |
| 2016-12-05 | 292262001 | 0.630 ppm |
| 2016-12-05 | 292262001 | 0.640 ppm |
| 2017-01-09 | 296067001 | 0.575 ppm |
| 2017-01-09 | 296067001 | 0.690 ppm |
| 2017-02-06 | 299455001 | 0.614 ppm |
| 2017-02-06 | 299455001 | 0.690 ppm |
| 2017-03-07 | 303404001 | 0.612 ppm |
| 2017-03-07 | 303404001 | 0.640 ppm |
| 2017-04-03 | 980849 | 0.740 ppm |
| 2017-04-12 | 309800001 | 0.629 ppm |
| 2017-04-12 | 309800001 | 0.660 ppm |
| 2017-05-02 | 313984001 | 0.665 ppm |
| 2017-05-02 | 313984001 | 0.681 ppm |
| 2017-06-05 | 320534001 | 0.600 ppm |
| 2017-06-05 | 320534001 | 0.650 ppm |
| 2017-07-05 | 326629001 | 0.610 ppm |
| 2017-07-05 | 326629001 | 0.634 ppm |
| 2017-08-08 | 336300001 | 0.620 ppm |
| 2017-08-08 | 336300001 | 0.644 ppm |
| 2017-09-06 | 340715001 | 0.660 ppm |
| 2017-09-06 | 340715001 | 0.704 ppm |
| 2017-10-02 | 347160001 | 0.616 ppm |
| 2017-10-02 | 347160001 | 0.680 ppm |
| 2017-11-06 | 353531001 | 0.628 ppm |
| 2017-11-06 | 353531001 | 0.650 ppm |
| 2017-12-04 | 358306001 | 0.567 ppm |
| 2017-12-04 | 358306001 | 0.595 ppm |
| 2018-01-02 | 361416001 | 0.643 ppm |
| 2018-01-02 | 361416001 | 0.702 ppm |
| 2018-02-05 | 365887001 | 0.661 ppm |
| 2018-02-05 | 365887001 | 0.720 ppm |
| 2018-02-26 | 1042388 | 0.490 ppm |
| 2018-03-06 | 370241001 | 0.613 ppm |
| 2018-03-06 | 370241001 | 0.629 ppm |
| 2018-04-02 | 374719001 | 0.574 ppm |
| 2018-04-02 | 374719001 | 0.630 ppm |
| 2018-05-10 | 381524001 | 0.644 ppm |
| 2018-05-10 | 381524001 | 0.667 ppm |
| 2018-06-07 | 387317001 | 0.571 ppm |
| 2018-06-07 | 387317001 | 0.630 ppm |
| 2018-07-05 | 392438001 | 0.660 ppm |
| 2018-07-05 | 392438001 | 0.669 ppm |
| 2018-08-06 | 399893001 | 0.626 ppm |
| 2018-08-06 | 399893001 | 0.720 ppm |
| 2018-09-04 | 405862001 | 0.597 ppm |
| 2018-09-04 | 405862001 | 0.643 ppm |
| 2018-10-02 | 412719001 | 0.609 ppm |
| 2018-10-02 | 412719001 | 0.646 ppm |
| 2018-11-06 | 418890001 | 0.609 ppm |
| 2018-11-06 | 418890001 | 0.653 ppm |
| 2018-12-05 | 424421001 | 0.628 ppm |
| 2018-12-05 | 424421001 | 0.660 ppm |
| 2019-01-07 | 427404001 | 0.625 ppm |
| 2019-01-07 | 427404001 | 0.650 ppm |
| 2019-02-06 | 430723001 | 0.647 ppm |
| 2019-02-06 | 430723001 | 0.770 ppm |
| 2019-02-13 | 1104970 | 0.180 ppm |
| 2019-03-05 | 434424001 | 0.628 ppm |
| 2019-03-05 | 434424001 | 0.630 ppm |
| 2019-04-02 | 438924001 | 0.606 ppm |
| 2019-04-02 | 438924001 | 0.670 ppm |
| 2019-05-08 | 445285001 | 0.646 ppm |
| 2019-05-08 | 445285001 | 0.660 ppm |
| 2019-06-04 | 450379001 | 0.611 ppm |
| 2019-06-04 | 450379001 | 0.634 ppm |
| 2019-07-08 | 457231001 | 0.660 ppm |
| 2019-07-08 | 457231001 | 0.699 ppm |
| 2019-08-05 | 462633001 | 0.623 ppm |
| 2019-08-05 | 462633001 | 0.653 ppm |
| 2019-09-04 | 468740001 | 0.641 ppm |
| 2019-09-04 | 468740001 | 0.649 ppm |
| 2019-10-02 | 474493001 | 0.653 ppm |
| 2019-10-02 | 474493001 | 0.661 ppm |
| 2019-11-06 | 480542001 | 0.669 ppm |
| 2019-11-06 | 480542001 | 0.710 ppm |
| 2019-12-03 | 484766001 | 0.599 ppm |
| 2019-12-03 | 484766001 | 0.627 ppm |