Selenium
Cal-water Service Company - Marysville
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.
121
Samples
0
Samples exceeding legal limit (MCL)
0
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 | 0.669 ppb | 41 | 38 | ND - 2.23 ppb |
| 2015 | 0.670 ppb | 29 | 16 | ND - 2.53 ppb |
| 2016 | ND | 19 | 0 | ND |
| 2017 | ND | 15 | 0 | ND |
| 2018 | ND | 15 | 0 | ND |
| 2019 | ND | 2 | 0 | ND |
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 |
|---|---|---|
| 2014-05-03 | 5701-019-1549 | 0.561 ppb |
| 2014-05-04 | 5701-011-0819 | 2.23 ppb |
| 2014-05-04 | 5701-015-1122 | 0.510 ppb |
| 2014-05-04 | 5701-018-1559 | 1.04 ppb |
| 2014-05-04 | 5701-020-1126 | 0.506 ppb |
| 2014-05-19 | 5810-011-1320 | ND |
| 2014-06-02 | 5701-011-0839 | 2.05 ppb |
| 2014-06-02 | 5701-015-0822 | 0.437 ppb |
| 2014-06-02 | 5701-020-0824 | 0.344 ppb |
| 2014-06-03 | 5701-018-0850 | 0.502 ppb |
| 2014-06-03 | 5701-019-1008 | 0.470 ppb |
| 2014-07-07 | 5701-009-1145 | 1.21 ppb |
| 2014-07-07 | 5701-011-0833 | 1.60 ppb |
| 2014-07-07 | 5701-012-0948 | 0.306 ppb |
| 2014-07-07 | 5701-015-1349 | 0.307 ppb |
| 2014-07-07 | 5701-016-1415 | 0.331 ppb |
| 2014-07-07 | 5701-018-1417 | 0.348 ppb |
| 2014-07-07 | 5701-019-0949 | 0.294 ppb |
| 2014-07-07 | 5701-020-1347 | 0.251 ppb |
| 2014-08-02 | 5701-011-0953 | 1.98 ppb |
| 2014-09-07 | 5701-011-0840 | 1.34 ppb |
| 2014-09-07 | 5701-015-0814 | 0.269 ppb |
| 2014-09-07 | 5701-018-1104 | 0.409 ppb |
| 2014-09-07 | 5701-019-1139 | 0.472 ppb |
| 2014-09-07 | 5701-020-0815 | 0.311 ppb |
| 2014-10-01 | 5701-008-1220 | 0.335 ppb |
| 2014-10-01 | 5701-009-1050 | 1.14 ppb |
| 2014-10-02 | 5701-016-1205 | 0.542 ppb |
| 2014-10-02 | 5701-018-1206 | 0.419 ppb |
| 2014-10-03 | 5701-015-1049 | 0.336 ppb |
| 2014-10-03 | 5701-020-1050 | 0.317 ppb |
| 2014-10-04 | 5701-012-1420 | 0.426 ppb |
| 2014-10-04 | 5701-019-1421 | 0.313 ppb |
| 2014-10-06 | 5701-011-0921 | 1.47 ppb |
| 2014-10-06 | 5701-013-1207 | 0.193 ppb |
| 2014-10-12 | 5701-011-0829 | 1.55 ppb |
| 2014-10-14 | 5810-013-1318 | ND |
| 2014-10-27 | 5701-011-0924 | 1.47 ppb |
| 2014-11-17 | 5810-008-1318 | ND |
| 2014-12-13 | 5701-020-1324 | 0.410 ppb |
| 2014-12-14 | 5701-018-0957 | 0.443 ppb |
| 2015-01-12 | 5810-009-1329 | ND |
| 2015-01-12 | 5810-012-1414 | ND |
| 2015-04-01 | 5701-015-1356 | 0.696 ppb |
| 2015-04-01 | 5701-020-1558 | 0.729 ppb |
| 2015-04-02 | 5701-011-1532 | 2.42 ppb |
| 2015-04-02 | 5701-012-1514 | 0.806 ppb |
| 2015-04-02 | 5701-019-1515 | 0.724 ppb |
| 2015-04-02 | 5701-023-1534 | 2.53 ppb |
| 2015-04-03 | 5701-009-0907 | 1.24 ppb |
| 2015-04-03 | 5701-016-1122 | 1.28 ppb |
| 2015-04-03 | 5701-018-1123 | 1.49 ppb |
| 2015-04-06 | 5810-010-1310 | ND |
| 2015-05-12 | 5701-020-1327 | 0.538 ppb |
| 2015-05-13 | 5701-011-0952 | 2.02 ppb |
| 2015-05-13 | 5701-018-0837 | 1.02 ppb |
| 2015-05-13 | 5701-023-0954 | 1.89 ppb |
| 2015-06-01 | 5701-015-1302 | 0.488 ppb |
| 2015-06-01 | 5701-018-1005 | 1.03 ppb |
| 2015-06-01 | 5701-019-1303 | 0.557 ppb |
| 2015-08-19 | 5810-015-1053 | ND |
| 2015-09-06 | 5701-019-1601 | ND |
| 2015-09-07 | 5701-011-0913 | ND |
| 2015-09-07 | 5701-015-1607 | ND |
| 2015-09-07 | 5701-018-0809 | ND |
| 2015-09-07 | 5701-020-1608 | ND |
| 2015-09-07 | 5701-023-0910 | ND |
| 2015-12-01 | 5701-011-1311 | ND |
| 2015-12-01 | 5701-018-1543 | ND |
| 2015-12-01 | 5701-023-1312 | ND |
| 2016-02-16 | 5810-016-1429 | ND |
| 2016-03-02 | 5701-011-1003 | ND |
| 2016-03-02 | 5701-018-1257 | ND |
| 2016-03-02 | 5701-023-1001 | ND |
| 2016-03-07 | 5810-011-1306 | ND |
| 2016-04-05 | 5701-009-0830 | ND |
| 2016-04-05 | 5701-011-0843 | ND |
| 2016-04-05 | 5701-013-1006 | ND |
| 2016-04-05 | 5701-016-1017 | ND |
| 2016-04-05 | 5701-018-1019 | ND |
| 2016-04-05 | 5701-023-0840 | ND |
| 2016-05-02 | 5701-018-1124 | ND |
| 2016-05-02 | 5701-023-0847 | ND |
| 2016-06-09 | 5701-008-0935 | ND |
| 2016-06-09 | 5701-009-1002 | ND |
| 2016-07-05 | 5701-020-1313 | ND |
| 2016-07-05 | 5701-023-1338 | ND |
| 2016-07-06 | 5701-018-1008 | ND |
| 2016-12-20 | 5810-008-1305 | ND |
| 2017-01-05 | 5701-009-1554 | ND |
| 2017-01-05 | 5701-011-1011 | ND |
| 2017-01-05 | 5701-016-1317 | ND |
| 2017-01-05 | 5701-018-1319 | ND |
| 2017-01-05 | 5701-023-1013 | ND |
| 2017-02-02 | 5701-011-0946 | ND |
| 2017-02-02 | 5701-018-1206 | ND |
| 2017-02-02 | 5701-023-0948 | ND |
| 2017-03-22 | 5810-013-1401 | ND |
| 2017-04-05 | 5701-009-1005 | ND |
| 2017-04-05 | 5701-011-1400 | ND |
| 2017-04-05 | 5701-013-1021 | ND |
| 2017-04-05 | 5701-016-1339 | ND |
| 2017-04-05 | 5701-018-1341 | ND |
| 2017-04-05 | 5701-023-1402 | ND |
| 2018-01-14 | 5701-015-1440 | ND |
| 2018-01-15 | 5701-012-1526 | ND |
| 2018-01-17 | 5810-009-1400 | ND |
| 2018-02-05 | 5701-018-1411 | ND |
| 2018-02-05 | 5701-023-1122 | ND |
| 2018-03-13 | 5701-011-1308 | ND |
| 2018-03-13 | 5701-018-1450 | ND |
| 2018-04-09 | 5701-016-1441 | ND |
| 2018-04-09 | 5701-018-1444 | ND |
| 2018-04-09 | 5701-023-1009 | ND |
| 2018-04-10 | 5701-013-1300 | ND |
| 2018-04-17 | 5810-010-1316 | ND |
| 2018-05-15 | 5810-012-1433 | ND |
| 2018-08-07 | 5810-015-1355 | ND |
| 2018-08-13 | 5701-011-1109 | ND |
| 2019-02-13 | 5810-016-1035 | ND |
| 2019-03-19 | 5810-011-1316 | ND |