EWG's Tap Water Database — 2019 UPDATE



Charlotte Water

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 exceeding legal limit (MCL)


Samples exceeding
health guidelines

Testing results - average by year

YearAverage resultSamples takenDetectionsRange of results
20120.579 ppm10100.520 ppm - 0.650 ppm
20130.584 ppm14140.520 ppm - 0.660 ppm
20140.600 ppm20200.500 ppm - 0.660 ppm
20150.603 ppm20200.520 ppm - 0.660 ppm
20160.626 ppm20200.580 ppm - 0.690 ppm
20170.627 ppm20200.550 ppm - 0.690 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
2012-02-09AE17669-IOC0.550 ppm
2012-02-09AE17670-IOC0.520 ppm
2012-02-09AE17671-IOC0.560 ppm
2012-02-09AE17672-IOC0.560 ppm
2012-02-09AE17673-IOC0.590 ppm
2012-08-07AE36181-IOC0.550 ppm
2012-08-07AE36182-IOC0.560 ppm
2012-08-07AE36183-IOC0.630 ppm
2012-08-07AE36184-IOC0.650 ppm
2012-08-07AE36185-IOC0.620 ppm
2013-02-14AE55318-IOC0.530 ppm
2013-02-14AE55319-IOC0.520 ppm
2013-02-14AE55322-IOC0.520 ppm
2013-05-14AE64330-IOC0.580 ppm
2013-05-14AE64331-IOC0.570 ppm
2013-05-14AE64334-IOC0.580 ppm
2013-08-19AE73824-IOC0.580 ppm
2013-08-19AE73825-IOC0.590 ppm
2013-08-19AE73826-IOC0.610 ppm
2013-11-13AE82850-IOC0.600 ppm
2013-11-13AE82851-IOC0.600 ppm
2013-11-13AE82854-IOC0.580 ppm
2013-11-13AE82852-IOC0.650 ppm
2013-11-13AE828530.660 ppm
2014-02-19AE92460-IOC0.530 ppm
2014-02-19AE92461-IOC0.510 ppm
2014-02-19AE92462-IOC0.500 ppm
2014-02-19AE92463-IOC0.520 ppm
2014-02-19AE92464-IOC0.520 ppm
2014-05-13AF01539-IOC0.620 ppm
2014-05-13AF01535-IOC0.590 ppm
2014-05-13AF01536-IOC0.630 ppm
2014-05-13AF01538-IOC0.640 ppm
2014-05-13AF01537-IOC0.620 ppm
2014-08-07AF10203-IOC0.650 ppm
2014-08-07AF10204-IOC0.650 ppm
2014-08-07AF10207-IOC0.650 ppm
2014-08-07AF10205-IOC0.630 ppm
2014-08-07AF10206-IOC0.630 ppm
2014-12-03AF22248-IOC0.620 ppm
2014-12-03AF22249-IOC0.660 ppm
2014-12-03AF22245-IOC0.590 ppm
2014-12-03AF22250-IOC0.620 ppm
2014-12-03A22251-IOC0.620 ppm
2015-03-040.520 ppm
2015-03-040.640 ppm
2015-03-040.620 ppm
2015-03-040.540 ppm
2015-03-040.640 ppm
2015-06-110.620 ppm
2015-06-110.600 ppm
2015-06-110.620 ppm
2015-06-240.560 ppm
2015-06-240.560 ppm
2015-08-100.660 ppm
2015-08-100.600 ppm
2015-08-100.630 ppm
2015-08-100.590 ppm
2015-08-100.660 ppm
2015-11-040.640 ppm
2015-11-040.560 ppm
2015-11-040.600 ppm
2015-11-040.640 ppm
2015-11-040.550 ppm
2016-02-03AF65972_IOC0.660 ppm
2016-02-03AF65968_IOC0.630 ppm
2016-02-03AF65971_IOC0.580 ppm
2016-02-03AF65969_IOC0.630 ppm
2016-02-03AF65970_IOC0.580 ppm
2016-05-04AF76708_IOC0.630 ppm
2016-05-04AF76704_IOC0.610 ppm
2016-05-04AF76709_IOC0.600 ppm
2016-05-04AF76703_IOC0.600 ppm
2016-05-04AF76707_IOC0.640 ppm
2016-08-03AF87876_IOC0.580 ppm
2016-08-03AF87872_IOC0.660 ppm
2016-08-03AF87874_IOC0.660 ppm
2016-08-03AF87877_IOC0.580 ppm
2016-08-03AF87888_IOC0.690 ppm
2016-11-02AF98939_IOC0.680 ppm
2016-11-02AF98937_IOC0.610 ppm
2016-11-02AF98938_IOC0.610 ppm
2016-11-02AF98936_IOC0.640 ppm
2016-11-02AF98935_IOC0.650 ppm
2017-02-01AG08742_IOC0.650 ppm
2017-02-01AG08738_IOC0.550 ppm
2017-02-01AG08739_IOC0.550 ppm
2017-02-01AG08740_IOC0.660 ppm
2017-02-01AG08741_IOC0.630 ppm
2017-05-04AG19796_IOC0.630 ppm
2017-05-04AG19792_IOC0.570 ppm
2017-05-04AG19793_IOC0.560 ppm
2017-05-08AG20107_IOC0.630 ppm
2017-05-08AG20108_IOC0.620 ppm
2017-08-01AG30321_IOC0.680 ppm
2017-08-01AG30317_IOC0.650 ppm
2017-08-01AG30319_IOC0.610 ppm
2017-08-01AG30320_IOC0.600 ppm
2017-08-01AG30318_IOC0.650 ppm
2017-11-01AG41977_IOC0.690 ppm
2017-11-01AG41980_IOC0.640 ppm
2017-11-01AG41978_IOC0.660 ppm
2017-11-01AG41979_IOC0.670 ppm
2017-11-01AG41981_IOC0.640 ppm