EWG's Tap Water Database — 2021 UPDATE



Lee County Utilities

Selenium is an essential element in diets. But too much selenium can decrease thyroid hormone production and cause hair loss, skin lesions and brittle fingernails.





Samples exceeding legal limit (MCL)


Samples exceeding
health guidelines

Testing results - average by year

YearAverage resultSamples takenDetectionsRange of results
20141.36 ppb550.900 ppb - 2.20 ppb
20150.900 ppb110.900 ppb
20164.10 ppb114.10 ppb
20171.28 ppb54ND - 3.60 ppb
20180.250 ppb42ND - 0.500 ppb
20191.10 ppb220.800 ppb - 1.40 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 30 ppb

The EWG Health Guideline of 30 ppb for selenium was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against hair loss and nail damage.

EPA Maximum Contaminant
Level (MCL) 50 ppb

The legal limit for selenium, established in 1991, was based on human epidemiological studies of populations exposed to naturally occurring selenium in drinking water. This limit does not include any additional consideration of children’s health.

ppb = parts per billion

All test results

Date Result
2014-02-051.30 ppb
2014-03-032.20 ppb
2014-04-160.900 ppb
2014-04-161.30 ppb
2014-10-081.10 ppb
2015-10-120.900 ppb
2016-10-034.10 ppb
2017-02-011.40 ppb
2017-03-020.900 ppb
2017-04-030.500 ppb
2017-04-033.60 ppb
2018-06-110.500 ppb
2018-10-160.500 ppb
2019-01-071.40 ppb
2019-10-070.800 ppb