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EWG's Tap Water Database — 2021 UPDATE

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Perchlorate

Santa Clarita Water Division

Perchlorate, a component of rocket fuel, occurs both naturally and as a synthetic chemical. Ingested perchlorate interferes with thyroid function. Exposure to perchlorate during pregnancy and childhood can impair cognitive development. Read More.

According to the EPA, perchlorate likely contaminates the water of more than 16 million Americans. Perchlorate interferes with iodine uptake in the thyroid, which can result in reduced thyroid hormones and an impact on metabolism, physical development and cognitive development. Children and developing fetuses are the most at risk from perchlorate contamination.

Perchlorate is the only unregulated contaminant for which the EPA has attempted to set a federal drinking water standard since 1996. However, the agency has yet to propose a draft limit for this contaminant. Perchlorate in drinking water is regulated in Arizona, California, Massachusetts, New Jersey, New York and Texas. California set a public health goal of 1 part per billion for perchlorate in 2015.

Click here to read more about perchlorate.

MORE ABOUT THIS CONTAMINANT

 

81

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2014ND130ND
2015ND110ND
2016ND150ND
2017ND150ND
2018ND140ND
2019ND130ND

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 1 ppb

The EWG Health Guideline of 1 ppb for perchlorate 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 hormone disruption.

ppb = parts per billion

All test results

Date Lab ID Result
2014-06-112104-040-0855ND
2014-06-112104-002-1010ND
2014-06-112104-006-0950ND
2014-06-112104-007-0845ND
2014-06-112104-008-1035ND
2014-06-112104-009-1030ND
2014-06-112104-012-0955ND
2014-06-112104-013-1100ND
2014-06-112104-014-1110ND
2014-06-112104-015-0920ND
2014-06-112104-016-1025ND
2014-06-112104-025-1000ND
2014-06-112104-039-0830ND
2015-06-032104-015-0845ND
2015-06-032104-040-0905ND
2015-06-032104-039-1035ND
2015-06-032104-019-0900ND
2015-06-032104-016-0840ND
2015-06-032104-002-0950ND
2015-06-032104-012-0825ND
2015-06-032104-006-0945ND
2015-06-032104-007-0920ND
2015-06-102104-009-0845ND
2015-08-272104-025-0945ND
2016-01-299590-013-1110ND
2016-03-292104-014-1335ND
2016-06-012104-009-0900ND
2016-06-012104-002-0935ND
2016-06-012104-006-0915ND
2016-06-012104-007-1020ND
2016-06-012104-040-1030ND
2016-06-012104-039-1010ND
2016-06-012104-025-0940ND
2016-06-012104-019-0835ND
2016-06-012104-016-0850ND
2016-06-012104-015-1040ND
2016-06-012104-014-1030ND
2016-06-012104-012-0950ND
2016-06-012104-013-1020ND
2017-02-012104-008-0950ND
2017-06-082104-014-1050ND
2017-06-082104-009-0945ND
2017-06-082104-006-1115ND
2017-06-082104-007-0920ND
2017-06-082104-012-1120ND
2017-06-082104-039-0940ND
2017-06-082104-025-1030ND
2017-06-082104-019-1000ND
2017-06-082104-013-1030ND
2017-06-082104-016-0950ND
2017-06-082104-015-1015ND
2017-06-082104-008-1145ND
2017-10-042104-002-0849ND
2017-12-042104-040-1345ND
2018-06-062104-014-0920ND
2018-06-062104-002-1030ND
2018-06-062104-009-1015ND
2018-06-062104-006-1000ND
2018-06-062104-008-1030ND
2018-06-062104-040-0855ND
2018-06-062104-007-0840ND
2018-06-062104-012-1045ND
2018-06-062104-016-1010ND
2018-06-062104-019-0845ND
2018-06-062104-025-1110ND
2018-06-062104-013-0900ND
2018-06-062104-039-0920ND
2018-07-262104-006-0930ND
2019-06-052104-006-1135ND
2019-06-052104-016-0959ND
2019-06-052104-002-1125ND
2019-06-052104-019-0834ND
2019-06-052104-009-0950ND
2019-06-052104-014-0848ND
2019-06-052104-012-1051ND
2019-06-052104-008-1013ND
2019-06-052104-013-0902ND
2019-06-052104-040-0923ND
2019-06-052104-025-1037ND
2019-06-052104-039-0905ND
2019-08-072104-007-0930ND