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EWG's Tap Water Database — 2021 UPDATE

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Perchlorate

Cal-am Water Company - Duarte

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

 

67

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2013N/A00N/A
2014ND150ND
2015ND140ND
2016ND150ND
2017ND70ND
2018ND70ND
2019ND90ND

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
2014-06-231225-003-1110ND
2014-06-231225-019-1205ND
2014-06-231225-010-1330ND
2014-06-231225-002-1300ND
2014-06-231225-007-1040ND
2014-06-231225-009-1135ND
2014-06-231225-008-1235ND
2014-09-039588-008-1120ND
2014-09-039588-002-1055ND
2014-09-039588-003-1215ND
2014-09-039588-004-1150ND
2014-09-039588-007-1240ND
2014-09-039588-009-1200ND
2014-09-039588-010-1225ND
2014-09-039588-019-1255ND
2015-09-089588-007-1215ND
2015-09-089588-019-1250ND
2015-09-089588-008-1120ND
2015-09-089588-010-1110ND
2015-09-089588-009-1130ND
2015-09-089588-003-1140ND
2015-09-089588-002-1200ND
2015-09-281225-007-1200ND
2015-09-281225-008-1330ND
2015-09-281225-003-1050ND
2015-09-281225-010-0945ND
2015-09-281225-009-1345ND
2015-10-141225-002-1205ND
2015-10-141225-019-0945ND
2016-06-201225-019-1115ND
2016-06-201225-008-1145ND
2016-06-201225-010-1135ND
2016-07-201225-009-1030ND
2016-07-201225-002-1110ND
2016-07-201225-003-1000ND
2016-07-201225-007-0930ND
2016-09-079588-003-1305ND
2016-09-079588-010-1315ND
2016-09-079588-007-1245ND
2016-09-079588-008-1345ND
2016-09-079588-002-1330ND
2016-09-079588-009-1400ND
2016-09-079588-019-1230ND
2016-09-121225-019-0850ND
2017-06-089588-007-1215ND
2017-06-089588-009-1250ND
2017-06-089588-002-1325ND
2017-06-089588-019-1115ND
2017-06-089588-008-1305ND
2017-06-089588-003-1230ND
2017-06-089588-010-1335ND
2018-06-149588-003-1225ND
2018-06-149588-019-1120ND
2018-06-149588-007-1215ND
2018-06-149588-002-1245ND
2018-06-149588-009-1235ND
2018-06-149588-010-1255ND
2018-09-209588-008-1240ND
2019-02-069590-022-1230ND
2019-05-139588-002-1230ND
2019-05-139588-008-1215ND
2019-05-139588-003-1155ND
2019-05-139588-007-1250ND
2019-05-139588-019-1100ND
2019-05-139588-009-1210ND
2019-05-139588-010-1145ND
2019-08-079588-022-0000ND