Fluoride
California Water Service Company - Palos Verde
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 | 0.837 ppm | 22 | 22 | 0.792 ppm - 0.905 ppm |
| 2015 | 0.783 ppm | 24 | 24 | 0.720 ppm - 0.873 ppm |
| 2016 | 0.706 ppm | 24 | 24 | 0.678 ppm - 0.748 ppm |
| 2017 | 0.702 ppm | 24 | 24 | 0.620 ppm - 0.813 ppm |
| 2018 | 0.757 ppm | 24 | 24 | 0.647 ppm - 0.840 ppm |
| 2019 | 0.703 ppm | 24 | 24 | 0.613 ppm - 0.881 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 |
|---|---|---|
| 2014-01-06 | 5701-001-0951 | 0.905 ppm |
| 2014-01-06 | 5701-801-0958 | 0.902 ppm |
| 2014-02-10 | 5701-001-0947 | 0.833 ppm |
| 2014-02-10 | 5701-801-0951 | 0.843 ppm |
| 2014-03-12 | 5701-001-1001 | 0.844 ppm |
| 2014-03-12 | 5701-801-1027 | 0.841 ppm |
| 2014-05-12 | 5701-001-1023 | 0.807 ppm |
| 2014-05-12 | 5701-801-1030 | 0.809 ppm |
| 2014-06-09 | 5701-001-1013 | 0.834 ppm |
| 2014-06-09 | 5701-801-1020 | 0.821 ppm |
| 2014-07-07 | 5701-001-0952 | 0.811 ppm |
| 2014-07-07 | 5701-801-0959 | 0.813 ppm |
| 2014-08-07 | 5701-001-0933 | 0.807 ppm |
| 2014-08-07 | 5701-801-0942 | 0.807 ppm |
| 2014-09-08 | 5701-001-1033 | 0.794 ppm |
| 2014-09-08 | 5701-801-1041 | 0.792 ppm |
| 2014-10-13 | 5701-001-1006 | 0.833 ppm |
| 2014-10-13 | 5701-801-1014 | 0.846 ppm |
| 2014-11-03 | 5701-001-1006 | 0.856 ppm |
| 2014-11-03 | 5701-801-1016 | 0.849 ppm |
| 2014-12-01 | 5701-001-0953 | 0.883 ppm |
| 2014-12-01 | 5701-801-1005 | 0.874 ppm |
| 2015-01-05 | 5701-001-0949 | 0.844 ppm |
| 2015-01-05 | 5701-801-0958 | 0.843 ppm |
| 2015-02-09 | 5701-001-1010 | 0.837 ppm |
| 2015-02-09 | 5701-801-1018 | 0.829 ppm |
| 2015-03-09 | 5701-001-1024 | 0.825 ppm |
| 2015-03-09 | 5701-801-1033 | 0.830 ppm |
| 2015-04-06 | 5701-001-0955 | 0.868 ppm |
| 2015-04-06 | 5701-801-1008 | 0.873 ppm |
| 2015-05-04 | 5701-001-0955 | 0.863 ppm |
| 2015-05-04 | 5701-801-1030 | 0.858 ppm |
| 2015-06-08 | 5701-001-1015 | 0.762 ppm |
| 2015-06-08 | 5701-801-1022 | 0.754 ppm |
| 2015-07-13 | 5701-001-1005 | 0.725 ppm |
| 2015-07-13 | 5701-801-1012 | 0.728 ppm |
| 2015-08-03 | 5701-001-1006 | 0.759 ppm |
| 2015-08-03 | 5701-801-1012 | 0.753 ppm |
| 2015-09-08 | 5701-001-1022 | 0.741 ppm |
| 2015-09-08 | 5701-801-1028 | 0.734 ppm |
| 2015-10-13 | 5701-001-0957 | 0.720 ppm |
| 2015-10-13 | 5701-801-1002 | 0.720 ppm |
| 2015-11-02 | 5701-001-0951 | 0.723 ppm |
| 2015-11-02 | 5701-801-0958 | 0.727 ppm |
| 2015-12-07 | 5701-001-1023 | 0.740 ppm |
| 2015-12-07 | 5701-801-1033 | 0.741 ppm |
| 2016-01-04 | 5701-001-1028 | 0.712 ppm |
| 2016-01-04 | 5701-801-1038 | 0.711 ppm |
| 2016-02-08 | 5701-001-0955 | 0.678 ppm |
| 2016-02-08 | 5701-801-1000 | 0.678 ppm |
| 2016-03-07 | 5701-001-0959 | 0.705 ppm |
| 2016-03-07 | 5701-801-1004 | 0.696 ppm |
| 2016-04-04 | 5701-001-1036 | 0.704 ppm |
| 2016-04-04 | 5701-801-1042 | 0.703 ppm |
| 2016-05-05 | 5701-001-1046 | 0.748 ppm |
| 2016-05-05 | 5701-801-1054 | 0.746 ppm |
| 2016-06-06 | 5701-001-1022 | 0.690 ppm |
| 2016-06-06 | 5701-801-1027 | 0.686 ppm |
| 2016-07-11 | 5701-001-0956 | 0.726 ppm |
| 2016-07-11 | 5701-801-1003 | 0.722 ppm |
| 2016-08-08 | 5701-001-1024 | 0.731 ppm |
| 2016-08-08 | 5701-801-1031 | 0.725 ppm |
| 2016-09-12 | 5701-001-1019 | 0.681 ppm |
| 2016-09-12 | 5701-801-1027 | 0.684 ppm |
| 2016-10-11 | 5701-001-0958 | 0.689 ppm |
| 2016-10-11 | 5701-801-1004 | 0.691 ppm |
| 2016-11-07 | 5701-001-1002 | 0.711 ppm |
| 2016-11-07 | 5701-801-1012 | 0.715 ppm |
| 2016-12-08 | 5701-001-1043 | 0.711 ppm |
| 2016-12-08 | 5701-801-1051 | 0.705 ppm |
| 2017-01-09 | 5701-001-1107 | 0.733 ppm |
| 2017-01-09 | 5701-801-1100 | 0.745 ppm |
| 2017-02-09 | 5701-001-1054 | 0.813 ppm |
| 2017-02-09 | 5701-801-1112 | 0.681 ppm |
| 2017-03-06 | 5701-001-1124 | 0.696 ppm |
| 2017-03-06 | 5701-801-1113 | 0.693 ppm |
| 2017-04-10 | 5701-001-1113 | 0.647 ppm |
| 2017-04-10 | 5701-801-1102 | 0.698 ppm |
| 2017-05-08 | 5701-001-1055 | 0.646 ppm |
| 2017-05-08 | 5701-801-1045 | 0.642 ppm |
| 2017-06-12 | 5701-001-1055 | 0.637 ppm |
| 2017-06-12 | 5701-801-1035 | 0.636 ppm |
| 2017-07-10 | 5701-001-1019 | 0.747 ppm |
| 2017-07-10 | 5701-801-1007 | 0.620 ppm |
| 2017-08-14 | 5701-001-1002 | 0.771 ppm |
| 2017-08-14 | 5701-801-1017 | 0.685 ppm |
| 2017-09-05 | 5701-001-1012 | 0.741 ppm |
| 2017-09-05 | 5701-801-1003 | 0.722 ppm |
| 2017-10-06 | 5701-001-0955 | 0.657 ppm |
| 2017-10-06 | 5701-801-0930 | 0.739 ppm |
| 2017-11-06 | 5701-001-1011 | 0.774 ppm |
| 2017-11-06 | 5701-801-1005 | 0.784 ppm |
| 2017-12-11 | 5701-001-1011 | 0.665 ppm |
| 2017-12-11 | 5701-801-1000 | 0.666 ppm |
| 2018-01-08 | 5701-001-1037 | 0.671 ppm |
| 2018-01-08 | 5701-801-1021 | 0.672 ppm |
| 2018-02-12 | 5701-001-1051 | 0.794 ppm |
| 2018-02-12 | 5701-801-1040 | 0.804 ppm |
| 2018-03-12 | 5701-001-1056 | 0.774 ppm |
| 2018-03-12 | 5701-801-1106 | 0.773 ppm |
| 2018-04-09 | 5701-001-1106 | 0.823 ppm |
| 2018-04-09 | 5701-801-1055 | 0.826 ppm |
| 2018-05-14 | 5701-001-1115 | 0.685 ppm |
| 2018-05-14 | 5701-801-1105 | 0.729 ppm |
| 2018-06-14 | 5701-001-0958 | 0.757 ppm |
| 2018-06-14 | 5701-801-1015 | 0.721 ppm |
| 2018-07-09 | 5701-001-1130 | 0.676 ppm |
| 2018-07-09 | 5701-801-1120 | 0.696 ppm |
| 2018-08-13 | 5701-001-1000 | 0.650 ppm |
| 2018-08-13 | 5701-801-1015 | 0.647 ppm |
| 2018-09-10 | 5701-001-1028 | 0.829 ppm |
| 2018-09-10 | 5701-801-1015 | 0.767 ppm |
| 2018-10-15 | 5701-001-1002 | 0.825 ppm |
| 2018-10-15 | 5701-801-1015 | 0.808 ppm |
| 2018-11-13 | 5701-001-1020 | 0.797 ppm |
| 2018-11-13 | 5701-801-1026 | 0.786 ppm |
| 2018-12-10 | 5701-001-1011 | 0.826 ppm |
| 2018-12-10 | 5701-801-1024 | 0.840 ppm |
| 2019-01-17 | 5701-001-1330 | 0.881 ppm |
| 2019-01-17 | 5701-801-1353 | 0.863 ppm |
| 2019-02-11 | 5701-001-1024 | 0.668 ppm |
| 2019-02-11 | 5701-801-1012 | 0.795 ppm |
| 2019-03-11 | 5701-001-1014 | 0.739 ppm |
| 2019-03-11 | 5701-801-1003 | 0.740 ppm |
| 2019-04-15 | 5810-001-0958 | 0.670 ppm |
| 2019-04-15 | 5810-801-1011 | 0.650 ppm |
| 2019-05-13 | 5701-001-1020 | 0.705 ppm |
| 2019-05-13 | 5701-801-1033 | 0.704 ppm |
| 2019-06-10 | 5701-001-0815 | 0.706 ppm |
| 2019-06-10 | 5701-801-0836 | 0.707 ppm |
| 2019-07-15 | 5701-001-1001 | 0.679 ppm |
| 2019-07-15 | 5701-801-1015 | 0.681 ppm |
| 2019-08-12 | 5701-001-1026 | 0.692 ppm |
| 2019-08-12 | 5701-801-1039 | 0.692 ppm |
| 2019-09-12 | 5701-001-1040 | 0.705 ppm |
| 2019-09-12 | 5701-801-1103 | 0.715 ppm |
| 2019-10-14 | 5701-001-1530 | 0.618 ppm |
| 2019-10-14 | 5701-801-1516 | 0.616 ppm |
| 2019-11-12 | 5701-001-1012 | 0.613 ppm |
| 2019-11-12 | 5701-801-1025 | 0.620 ppm |
| 2019-12-02 | 5701-001-1020 | 0.707 ppm |
| 2019-12-02 | 5701-801-1032 | 0.713 ppm |