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EWG's Tap Water Database — 2021 UPDATE

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Perchlorate

California Water Service (CWS) - Bakersfield

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

 

125

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2014ND170ND
2015ND220ND
2016ND240ND
2017ND160ND
2018ND230ND
2019ND230ND

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
2014-01-069588-026-1415ND
2014-01-149588-002-1005ND
2014-02-049588-009-0935ND
2014-02-249588-002-1050ND
2014-03-049588-253-0752ND
2014-06-049588-005-1240ND
2014-06-259588-018-1001ND
2014-06-259588-020-0917ND
2014-06-309588-021-1006ND
2014-07-219588-011-1114ND
2014-07-219588-031-1200ND
2014-07-299588-015-0940ND
2014-08-069588-024-1420ND
2014-10-069588-006-1035ND
2014-10-089588-050-0957ND
2014-10-099588-004-1330ND
2014-12-165810-003-2232ND
2015-03-029588-051-1515ND
2015-03-029588-072-1400ND
2015-03-129588-253-0850ND
2015-04-169588-038-1150ND
2015-04-209588-053-1304ND
2015-05-119590-105-1333ND
2015-05-119590-156-1100ND
2015-05-129590-096-1330ND
2015-07-089588-059-1412ND
2015-07-089588-068-1134ND
2015-08-059588-099-1358ND
2015-08-059588-160-1210ND
2015-08-109588-098-1030ND
2015-10-059588-079-1330ND
2015-10-069588-058-1045ND
2015-10-069588-091-1345ND
2015-10-069588-092-1339ND
2015-12-079588-069-1008ND
2015-12-099588-106-1300ND
2015-12-099588-163-1215ND
2015-12-109588-094-1315ND
2015-12-159588-108-1015ND
2016-01-049588-107-0900ND
2016-02-109588-122-1317ND
2016-03-179588-253-0725ND
2016-05-049588-124-1231ND
2016-05-059588-118-1355ND
2016-05-209588-110-1358ND
2016-05-209588-126-1306ND
2016-06-089588-148-1217ND
2016-06-159588-131-1032ND
2016-06-169588-055-1010ND
2016-06-179588-151-0940ND
2016-07-129588-109-1200ND
2016-08-039588-150-1000ND
2016-08-089588-149-1235ND
2016-08-089588-154-0950ND
2016-08-159588-125-1015ND
2016-09-079588-119-1110ND
2016-09-079588-143-1135ND
2016-09-079588-146-0955ND
2016-09-089588-052-1115ND
2016-09-229588-117-0940ND
2016-10-119588-129-1508ND
2016-10-189588-125-1045ND
2016-12-019588-056-1438ND
2017-01-109588-002-1005ND
2017-01-119588-026-1115ND
2017-03-149588-253-0907ND
2017-03-239588-021-0900ND
2017-04-109588-009-1135ND
2017-04-199588-004-1115ND
2017-06-129588-018-1045ND
2017-06-129588-050-1130ND
2017-06-139588-005-1130ND
2017-06-209588-015-1014ND
2017-06-269588-006-0950ND
2017-07-129588-003-0738ND
2017-07-189588-031-1103ND
2017-08-239588-024-1345ND
2017-09-119588-011-0952ND
2017-12-299588-020-0930ND
2018-03-149588-051-1123ND
2018-03-149588-072-1240ND
2018-03-229588-253-0842ND
2018-04-169588-038-1244ND
2018-04-179588-053-1401ND
2018-04-239588-094-1058ND
2018-05-019588-105-0955ND
2018-05-039588-096-1000ND
2018-05-099588-156-1142ND
2018-06-159590-026-0945ND
2018-07-129588-059-1316ND
2018-07-129588-092-1140ND
2018-07-129588-106-1316ND
2018-07-169588-056-1228ND
2018-07-169588-068-0928ND
2018-07-169588-091-1112ND
2018-08-139588-099-0933ND
2018-08-209588-098-0911ND
2018-08-279588-160-1153ND
2018-09-139588-058-0953ND
2018-10-229590-069-1135ND
2018-11-169588-048-1123ND
2018-11-209588-069-0955ND
2019-01-099588-107-1121ND
2019-02-139588-122-1026ND
2019-03-269588-253-1057ND
2019-05-149588-125-0840ND
2019-05-149588-126-0920ND
2019-05-149588-264-1207ND
2019-05-159588-118-1340ND
2019-05-299588-110-1140ND
2019-05-299588-124-0922ND
2019-06-109588-151-1056ND
2019-06-129588-148-1040ND
2019-07-099588-109-1420ND
2019-08-089588-117-1210ND
2019-08-089588-149-1036ND
2019-08-089588-154-1004ND
2019-09-109588-146-1025ND
2019-09-119588-143-0925ND
2019-09-249588-055-1330ND
2019-10-169588-052-1150ND
2019-10-289588-150-1130ND
2019-11-209588-108-0840ND
2019-11-219588-052-1235ND
2019-12-109588-119-0840ND