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EWG's Tap Water Database — 2019 UPDATE

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Selenium

California Water Service (CWS) - Salinas

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.

 

92

Samples

0

Samples exceeding legal limit (MCL)

1

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20126.63 ppb106ND - 35.0 ppb
20130.851 ppb142ND - 6.00 ppb
20143.14 ppb2217ND - 12.0 ppb
20155.34 ppb128ND - 12.0 ppb
20163.12 ppb155ND - 12.0 ppb
20173.79 ppb198ND - 13.5 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
2012-02-149590-106-1330ND
2012-02-149590-009-12505.70 ppb
2012-03-079590-037-1402ND
2012-03-089590-041-1146ND
2012-04-189590-010-11485.40 ppb
2012-04-199590-008-104035.0 ppb
2012-06-149590-006-10165.90 ppb
2012-07-249590-104-1438ND
2012-09-209590-005-11395.80 ppb
2012-09-265701-008-14028.47 ppb
2013-01-179590-017-1350ND
2013-01-239590-024-1258ND
2013-01-249590-022-1348ND
2013-01-249590-015-1045ND
2013-01-249590-043-1448ND
2013-01-299590-018-10046.00 ppb
2013-03-129590-023-1439ND
2013-03-129590-014-1335ND
2013-05-099590-102-1314ND
2013-05-099590-103-1457ND
2013-06-139590-020-1135ND
2013-09-115701-008-13515.92 ppb
2013-11-149590-123-1350ND
2013-12-269590-131-1159ND
2014-01-159590-019-1331ND
2014-04-229590-039-1112ND
2014-06-105701-104-13180.196 ppb
2014-06-165701-131-11401.44 ppb
2014-06-179590-026-12397.10 ppb
2014-07-095701-030-13406.84 ppb
2014-08-085701-102-14271.81 ppb
2014-08-085701-103-15131.99 ppb
2014-08-139590-028-135512.0 ppb
2014-08-135701-028-14149.32 ppb
2014-08-145701-123-09242.83 ppb
2014-08-259590-030-11057.70 ppb
2014-08-269590-029-1025ND
2014-09-259590-027-0937ND
2014-09-259590-046-1343ND
2014-10-035701-030-10246.91 ppb
2014-11-055701-006-10304.98 ppb
2014-11-125701-103-09391.56 ppb
2014-11-125701-102-10171.44 ppb
2014-11-125701-024-12100.578 ppb
2014-11-125701-123-14022.11 ppb
2014-11-125701-037-11260.363 ppb
2015-01-225701-023-11197.47 ppb
2015-01-225701-043-1358ND
2015-02-189590-106-1315ND
2015-02-189590-009-14006.30 ppb
2015-03-119590-041-1030ND
2015-03-119590-037-1110ND
2015-04-219590-008-145312.0 ppb
2015-06-039590-006-10108.50 ppb
2015-06-165701-104-14133.45 ppb
2015-07-229590-005-15367.70 ppb
2015-07-225701-023-10288.86 ppb
2015-10-205701-023-11219.78 ppb
2016-01-269590-020-1326ND
2016-01-279590-018-10206.70 ppb
2016-02-039590-022-1410ND
2016-02-109590-103-1330ND
2016-02-169590-103-1433ND
2016-02-229590-024-1515ND
2016-03-039590-015-1433ND
2016-05-035701-026-12497.98 ppb
2016-05-049590-017-1429ND
2016-05-129590-102-1427ND
2016-06-285701-023-13499.15 ppb
2016-06-289590-023-135811.0 ppb
2016-12-289590-027-1513ND
2016-12-289590-123-1442ND
2016-12-299590-008-141512.0 ppb
2017-01-109590-019-13555.00 ppb
2017-01-105701-023-1319ND
2017-02-085701-026-14217.32 ppb
2017-02-279590-027-1516ND
2017-03-029590-132-1050ND
2017-05-095701-026-13346.88 ppb
2017-06-275701-029-1025ND
2017-06-275701-018-1113ND
2017-08-159590-026-14269.50 ppb
2017-08-239590-029-1413ND
2017-09-199590-046-1423ND
2017-10-179590-030-13318.00 ppb
2017-10-175701-023-115213.5 ppb
2017-11-209590-014-1416ND
2017-11-209590-008-13419.80 ppb
2017-11-219590-104-1352ND
2017-11-219590-131-1252ND
2017-11-289590-043-1424ND
2017-11-299590-030-145512.0 ppb