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EWG's Tap Water Database — 2021 UPDATE

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Perchlorate

Chino Basin Desalter Authority - Desalter 1

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

 

90

Samples

0

Samples exceeding legal limit (MCL)

1

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20140.0933 ppb151ND - 1.40 ppb
2015ND150ND
2016ND150ND
2017ND120ND
2018ND170ND
2019ND160ND

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
2014-01-214790-021-1400ND
2014-07-024790-002-0745ND
2014-07-024790-001-0845ND
2014-07-024790-004-0600ND
2014-07-094790-005-0645ND
2014-07-094790-008-0745ND
2014-07-094790-007-0915ND
2014-07-094790-006-0845ND
2014-07-164790-013-0915ND
2014-07-164790-011-0800ND
2014-07-164790-010-0700ND
2014-07-164790-009-0600ND
2014-07-234790-020-0904ND
2014-07-234790-015-0600ND
2014-08-134790-014-09001.40 ppb
2015-07-014790-001-0910ND
2015-07-014790-004-1014ND
2015-07-014790-002-0830ND
2015-07-084790-010-1020ND
2015-07-084790-009-0915ND
2015-07-084790-008-0820ND
2015-07-084790-011-1123ND
2015-07-084790-005-0730ND
2015-07-154790-021-0730ND
2015-07-154790-021-0650ND
2015-07-154790-020-0730ND
2015-07-224790-007-1045ND
2015-07-224790-013-0945ND
2015-07-224790-006-1120ND
2015-07-224790-014-0853ND
2016-04-044790-015-0945ND
2016-07-064790-008-0650ND
2016-07-064790-009-0800ND
2016-07-064790-010-0910ND
2016-07-064790-005-0600ND
2016-07-134790-006-0700ND
2016-07-134790-007-0630ND
2016-07-134790-021-0800ND
2016-07-204790-014-0900ND
2016-07-204790-013-0800ND
2016-07-204790-020-1000ND
2016-07-204790-011-0700ND
2016-07-274790-001-0700ND
2016-07-274790-002-0730ND
2016-07-274790-004-0845ND
2017-07-124790-024-0630ND
2017-07-124790-023-0930ND
2017-07-124790-020-0600ND
2017-07-194790-011-0530ND
2017-07-194790-015-0830ND
2017-07-194790-014-0730ND
2017-07-194790-013-0630ND
2017-07-264790-006-0900ND
2017-07-264790-007-0930ND
2017-07-264790-021-0700ND
2017-08-024790-001-0700ND
2017-08-024790-004-0815ND
2018-07-124790-006-0930ND
2018-07-124790-007-1050ND
2018-07-124790-021-0700ND
2018-07-174790-009-1015ND
2018-07-174790-010-1100ND
2018-07-174790-005-0830ND
2018-07-174790-008-0715ND
2018-07-244790-014-0800ND
2018-07-244790-011-0635ND
2018-07-244790-013-0720ND
2018-07-244790-015-0900ND
2018-07-314790-001-0445ND
2018-07-314790-002-0530ND
2018-07-314790-004-0830ND
2018-08-074790-023-0945ND
2018-08-074790-024-1030ND
2018-08-144790-020-0730ND
2019-07-104790-001-1015ND
2019-07-104790-002-0915ND
2019-07-104790-004-1100ND
2019-07-174790-008-0830ND
2019-07-174790-010-0800ND
2019-07-174790-005-0745ND
2019-07-174790-009-0900ND
2019-07-244790-015-1000ND
2019-07-244790-014-0900ND
2019-07-244790-013-0930ND
2019-07-314790-006-1000ND
2019-07-314790-007-0900ND
2019-07-314790-021-0945ND
2019-08-074790-024-0730ND
2019-08-074790-023-0800ND
2019-08-144790-020-0830ND