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EWG's Tap Water Database — 2021 UPDATE

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Perchlorate

Compton Water Department

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.

 

40

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2014ND80ND
2015ND70ND
2016ND70ND
2017ND50ND
2018ND70ND
2019ND60ND

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
2014-04-179588-028-1043ND
2014-07-299588-019-0946ND
2014-07-299588-015-0933ND
2014-07-299588-013-0920ND
2014-07-299588-011-0906ND
2014-10-319588-014-1019ND
2014-10-319588-009-0934ND
2014-11-079588-015-1050ND
2015-04-169588-015-1120ND
2015-04-169588-028-0957ND
2015-07-249588-013-0945ND
2015-07-249588-019-1107ND
2015-07-249588-011-0934ND
2015-10-229588-014-0951ND
2015-10-229588-009-1112ND
2016-04-289588-015-1050ND
2016-05-259588-028-0944ND
2016-07-159588-011-1057ND
2016-07-159588-019-1048ND
2016-08-019588-013-0942ND
2016-10-059588-009-1045ND
2016-10-059588-014-1202ND
2017-04-269588-015-1056ND
2017-07-189588-019-1035ND
2017-07-189588-011-0950ND
2017-07-189588-013-1005ND
2017-12-119588-009-1032ND
2018-01-099588-009-1041ND
2018-04-129588-028-1100ND
2018-04-129588-015-1040ND
2018-06-289588-014-1015ND
2018-07-239588-013-1055ND
2018-07-239588-011-1035ND
2018-07-239588-019-0955ND
2019-01-309588-009-1125ND
2019-04-259588-028-0935ND
2019-04-259588-015-1050ND
2019-07-179588-019-0930ND
2019-07-179588-011-1005ND
2019-11-209588-013-1015ND