Fluoride
Hudson Waterworks
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 | 0.680 ppm | 29 | 29 | 0.130 ppm - 0.930 ppm |
| 2015 | 0.746 ppm | 28 | 28 | 0.570 ppm - 0.910 ppm |
| 2016 | 0.761 ppm | 24 | 24 | 0.620 ppm - 0.880 ppm |
| 2017 | 0.659 ppm | 31 | 31 | 0.0890 ppm - 0.860 ppm |
| 2018 | 0.778 ppm | 25 | 25 | 0.580 ppm - 1.43 ppm |
| 2019 | 0.763 ppm | 24 | 24 | 0.620 ppm - 0.939 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 |
|---|---|---|
| 2014-01-27 | 117613001 | 0.827 ppm |
| 2014-01-27 | 117613001 | 0.930 ppm |
| 2014-02-18 | 120125001 | 0.634 ppm |
| 2014-02-18 | 120125001 | 0.700 ppm |
| 2014-03-17 | 123758001 | 0.655 ppm |
| 2014-03-17 | 123758001 | 0.700 ppm |
| 2014-03-26 | 776787 | 0.130 ppm |
| 2014-03-26 | 776793 | 0.350 ppm |
| 2014-03-26 | 776790 | 0.790 ppm |
| 2014-03-31 | 777343 | 0.200 ppm |
| 2014-04-21 | 128491001 | 0.659 ppm |
| 2014-04-21 | 128491001 | 0.730 ppm |
| 2014-05-19 | 133700001 | 0.812 ppm |
| 2014-05-19 | 133700001 | 0.910 ppm |
| 2014-06-16 | 797092 | 0.140 ppm |
| 2014-06-16 | 139393001 | 0.760 ppm |
| 2014-06-16 | 139393001 | 0.804 ppm |
| 2014-07-21 | 146618001 | 0.674 ppm |
| 2014-07-21 | 146618001 | 0.700 ppm |
| 2014-08-18 | 152082001 | 0.666 ppm |
| 2014-08-18 | 152082001 | 0.750 ppm |
| 2014-09-22 | 159572001 | 0.740 ppm |
| 2014-09-22 | 159572001 | 0.754 ppm |
| 2014-10-20 | 164600001 | 0.760 ppm |
| 2014-10-20 | 164600001 | 0.837 ppm |
| 2014-11-17 | 168827001 | 0.690 ppm |
| 2014-11-17 | 168827001 | 0.783 ppm |
| 2014-12-15 | 172916001 | 0.801 ppm |
| 2014-12-15 | 172916001 | 0.820 ppm |
| 2015-01-20 | 176415001 | 0.659 ppm |
| 2015-01-20 | 176415001 | 0.840 ppm |
| 2015-02-17 | 180478001 | 0.734 ppm |
| 2015-02-17 | 180478001 | 0.750 ppm |
| 2015-02-23 | 180718001 | 0.725 ppm |
| 2015-02-23 | 180718001 | 0.910 ppm |
| 2015-03-16 | 183741001 | 0.783 ppm |
| 2015-03-16 | 183741001 | 0.900 ppm |
| 2015-04-20 | 188885001 | 0.716 ppm |
| 2015-04-20 | 188885001 | 0.810 ppm |
| 2015-05-18 | 196285001 | 0.728 ppm |
| 2015-05-18 | 196285001 | 0.780 ppm |
| 2015-05-26 | 195753001 | 0.680 ppm |
| 2015-05-26 | 195753001 | 0.722 ppm |
| 2015-06-15 | 199922001 | 0.760 ppm |
| 2015-06-15 | 199922001 | 0.809 ppm |
| 2015-07-13 | 205313001 | 0.650 ppm |
| 2015-07-13 | 205313001 | 0.738 ppm |
| 2015-08-10 | 210866001 | 0.680 ppm |
| 2015-08-10 | 210866001 | 0.736 ppm |
| 2015-09-08 | 216190001 | 0.570 ppm |
| 2015-09-08 | 216190001 | 0.689 ppm |
| 2015-10-19 | 224606001 | 0.700 ppm |
| 2015-10-19 | 224606001 | 0.878 ppm |
| 2015-11-09 | 227854001 | 0.700 ppm |
| 2015-11-09 | 227854001 | 0.764 ppm |
| 2015-12-07 | 231561001 | 0.704 ppm |
| 2015-12-07 | 231561001 | 0.770 ppm |
| 2016-01-11 | 235408001 | 0.750 ppm |
| 2016-01-11 | 235408001 | 0.788 ppm |
| 2016-02-08 | 238849001 | 0.725 ppm |
| 2016-02-08 | 238849001 | 0.730 ppm |
| 2016-03-07 | 243290001 | 0.727 ppm |
| 2016-03-07 | 243290001 | 0.790 ppm |
| 2016-04-11 | 248128001 | 0.796 ppm |
| 2016-04-11 | 248128001 | 0.820 ppm |
| 2016-05-09 | 253404001 | 0.750 ppm |
| 2016-05-09 | 253404001 | 0.781 ppm |
| 2016-06-13 | 260600001 | 0.770 ppm |
| 2016-06-13 | 260600001 | 0.818 ppm |
| 2016-07-11 | 265412001 | 0.760 ppm |
| 2016-07-11 | 265412001 | 0.807 ppm |
| 2016-08-08 | 271203001 | 0.620 ppm |
| 2016-08-08 | 271203001 | 0.739 ppm |
| 2016-09-12 | 277145001 | 0.780 ppm |
| 2016-09-12 | 277145001 | 0.801 ppm |
| 2016-10-11 | 283579001 | 0.630 ppm |
| 2016-10-11 | 283579001 | 0.730 ppm |
| 2016-11-07 | 287854001 | 0.700 ppm |
| 2016-11-07 | 287854001 | 0.728 ppm |
| 2016-12-12 | 292672001 | 0.854 ppm |
| 2016-12-12 | 292672001 | 0.880 ppm |
| 2017-01-09 | 295654001 | 0.740 ppm |
| 2017-01-09 | 295654001 | 0.790 ppm |
| 2017-02-14 | 300487001 | 0.771 ppm |
| 2017-02-14 | 300487001 | 0.820 ppm |
| 2017-03-13 | 303845001 | 0.800 ppm |
| 2017-03-13 | 303845001 | 0.860 ppm |
| 2017-04-03 | 980886 | 0.0980 ppm |
| 2017-04-03 | 980875 | 0.140 ppm |
| 2017-04-03 | 980884 | 0.160 ppm |
| 2017-04-03 | 980879 | 0.830 ppm |
| 2017-04-04 | 981150 | 0.0890 ppm |
| 2017-04-04 | 981147 | 0.140 ppm |
| 2017-04-05 | 981440 | 0.300 ppm |
| 2017-04-10 | 308925001 | 0.730 ppm |
| 2017-04-10 | 308925001 | 0.783 ppm |
| 2017-05-15 | 315972001 | 0.763 ppm |
| 2017-05-15 | 315972001 | 0.780 ppm |
| 2017-06-12 | 321330001 | 0.730 ppm |
| 2017-06-12 | 321330001 | 0.848 ppm |
| 2017-07-17 | 329223001 | 0.760 ppm |
| 2017-07-17 | 329223001 | 0.818 ppm |
| 2017-08-07 | 334024001 | 0.620 ppm |
| 2017-08-07 | 334024001 | 0.748 ppm |
| 2017-09-11 | 341380001 | 0.720 ppm |
| 2017-09-11 | 341380001 | 0.857 ppm |
| 2017-10-10 | 348286001 | 0.760 ppm |
| 2017-10-10 | 348286001 | 0.852 ppm |
| 2017-11-13 | 354274001 | 0.710 ppm |
| 2017-11-13 | 354274001 | 0.724 ppm |
| 2017-12-11 | 358869001 | 0.830 ppm |
| 2017-12-11 | 358869001 | 0.844 ppm |
| 2018-01-16 | 363085001 | 0.840 ppm |
| 2018-01-16 | 363085001 | 0.848 ppm |
| 2018-02-12 | 366678001 | 0.691 ppm |
| 2018-02-12 | 366678001 | 0.750 ppm |
| 2018-03-12 | 370803001 | 0.700 ppm |
| 2018-03-12 | 370803001 | 1.43 ppm |
| 2018-04-09 | 375385001 | 0.750 ppm |
| 2018-04-09 | 375385001 | 0.779 ppm |
| 2018-05-07 | 380521001 | 0.750 ppm |
| 2018-05-07 | 380521001 | 0.755 ppm |
| 2018-06-11 | 387911001 | 0.760 ppm |
| 2018-06-11 | 387911001 | 0.794 ppm |
| 2018-06-25 | 1063652 | 0.610 ppm |
| 2018-07-16 | 394813001 | 0.730 ppm |
| 2018-07-16 | 394813001 | 0.847 ppm |
| 2018-08-13 | 400767001 | 0.740 ppm |
| 2018-08-13 | 400767001 | 0.795 ppm |
| 2018-09-10 | 406623001 | 0.580 ppm |
| 2018-09-10 | 406623001 | 0.663 ppm |
| 2018-10-09 | 413569001 | 0.780 ppm |
| 2018-10-09 | 413569001 | 0.813 ppm |
| 2018-11-13 | 419878001 | 0.745 ppm |
| 2018-11-13 | 419878001 | 0.780 ppm |
| 2018-12-10 | 423616001 | 0.740 ppm |
| 2018-12-10 | 423616001 | 0.784 ppm |
| 2019-01-14 | 427840001 | 0.750 ppm |
| 2019-01-14 | 427840001 | 0.784 ppm |
| 2019-02-11 | 431047001 | 0.840 ppm |
| 2019-02-11 | 431047001 | 0.859 ppm |
| 2019-03-11 | 434874001 | 0.760 ppm |
| 2019-03-11 | 434874001 | 0.812 ppm |
| 2019-04-08 | 439438001 | 0.650 ppm |
| 2019-04-08 | 439438001 | 0.790 ppm |
| 2019-05-13 | 445820001 | 0.820 ppm |
| 2019-05-13 | 445820001 | 0.862 ppm |
| 2019-06-10 | 450983001 | 0.760 ppm |
| 2019-06-10 | 450983001 | 0.939 ppm |
| 2019-07-15 | 457794001 | 0.700 ppm |
| 2019-07-15 | 457794001 | 0.705 ppm |
| 2019-08-12 | 463136001 | 0.730 ppm |
| 2019-08-12 | 463136001 | 0.819 ppm |
| 2019-09-09 | 468718001 | 0.690 ppm |
| 2019-09-09 | 468718001 | 0.844 ppm |
| 2019-10-07 | 475041001 | 0.620 ppm |
| 2019-10-07 | 475041001 | 0.777 ppm |
| 2019-11-04 | 479650001 | 0.690 ppm |
| 2019-11-04 | 479650001 | 0.710 ppm |
| 2019-12-09 | 485306001 | 0.630 ppm |
| 2019-12-09 | 485306001 | 0.782 ppm |