Know Your Environment. Protect Your Health.

Selenium

Town of Poolesville

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.

 

18

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.745 ppb63ND - 1.88 ppb
2019N/A00N/A
2020N/A00N/A
2021ND40ND
20220.980 ppb74ND - 2.55 ppb
2023ND10ND

ppb = parts per billion

State, National, and Health Guidelines for Drinking Water

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
2018-12-176389_428_1_31.44 ppb
2018-12-176389_428_1_41.88 ppb
2018-12-176389_428_1_51.15 ppb
2018-12-176389_428_1_6ND
2018-12-176389_428_2ND
2018-12-176389_428_1_1ND
2021-01-21E21001855002ND
2021-04-06E21002756002ND
2021-08-05E22000418003ND
2021-08-05E22000418002ND
2022-07-19E2300012302ND
2022-07-19E2300012303ND
2022-07-19E2300012304ND
2022-12-13FWL0344_011.04 ppb
2022-12-13FWL0348_011.68 ppb
2022-12-13FWL0349_012.55 ppb
2022-12-13FWL0350_011.59 ppb
2023-10-18E2400146902ND