Selenium

City of Fullerton

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.

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Samples

Samples exceeding legal limit (MCL)

Samples exceeding
health guidelines

Testing results - average by year

Year	Average result	Samples taken	Detections	Range of results
2013	N/A	0	0	N/A
2014	N/A	0	0	N/A
2015	N/A	0	0	N/A
2016	0.469 ppb	13	1	ND - 6.10 ppb
2017	N/A	0	0	N/A
2018	N/A	0	0	N/A
2019	1.14 ppb	9	1	ND - 10.3 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	Lab ID	Result
2016-02-03	4417-010-1010	ND
2016-02-03	4417-012-0950	ND
2016-02-03	4417-014-0920	ND
2016-02-23	4417-015-0955	ND
2016-05-02	4417-007-1115	ND
2016-05-02	4417-021-1045	ND
2016-05-02	4417-010-0955	ND
2016-05-02	4417-011-0920	ND
2016-05-02	4417-018-0935	ND
2016-05-02	4417-012-1010	ND
2016-05-02	4417-014-0900	ND
2016-05-02	4417-016-1150	ND
2016-08-04	4417-001-1145	6.10 ppb
2019-03-05	4417-012-1205	ND
2019-03-05	4417-014-0915	ND
2019-03-20	4417-001-0945	10.3 ppb
2019-04-03	4417-007-1140	ND
2019-04-03	4417-021-1110	ND
2019-04-08	4417-015-1140	ND
2019-04-08	4417-016-1210	ND
2019-04-08	4417-018-0840	ND
2019-04-11	4417-011-1130	ND