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EWG's Tap Water Database — 2021 UPDATE

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Perchlorate

USMC - 29 Palms

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.

 

43

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
2014N/A00N/A
2015ND70ND
2016ND30ND
2017ND110ND
2018ND110ND
2019ND110ND

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
2015-01-264790-001-1100ND
2015-01-264790-005-1200ND
2015-01-264790-010-1245ND
2015-01-264790-004-1330ND
2015-01-264790-011-1450ND
2015-01-264790-013-1140ND
2015-03-024790-003-1100ND
2016-05-114790-008-1110ND
2016-05-114790-007-1130ND
2016-05-114790-006-1050ND
2017-02-224790-011-1135ND
2017-02-224790-010-1145ND
2017-02-224790-013-1020ND
2017-02-224790-009-1235ND
2017-02-224790-008-1205ND
2017-02-224790-001-1035ND
2017-02-224790-007-1120ND
2017-02-224790-006-1215ND
2017-02-224790-003-1005ND
2017-02-224790-004-1105ND
2017-02-224790-005-1050ND
2018-02-274790-006-1255ND
2018-02-274790-003-1100ND
2018-02-274790-004-1230ND
2018-02-274790-001-1140ND
2018-02-274790-007-1320ND
2018-02-274790-005-1200ND
2018-02-274790-013-1120ND
2018-02-284790-008-1145ND
2018-02-284790-009-1200ND
2018-02-284790-011-1130ND
2018-02-284790-010-1100ND
2019-01-304790-001-1100ND
2019-01-304790-011-1140ND
2019-01-304790-013-1050ND
2019-01-304790-010-1150ND
2019-01-304790-003-1040ND
2019-01-304790-009-1210ND
2019-01-304790-008-1200ND
2019-01-304790-004-1120ND
2019-01-304790-007-1130ND
2019-01-304790-005-1110ND
2019-01-304790-006-1220ND