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EWG's Tap Water Database — 2021 UPDATE

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Perchlorate

Rubidoux Community SD

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

 

206

Samples

0

Samples exceeding legal limit (MCL)

28

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20141.08 ppb215ND - 5.40 ppb
20150.664 ppb365ND - 5.50 ppb
20161.20 ppb4011ND - 5.50 ppb
20170.414 ppb444ND - 5.20 ppb
20180.337 ppb302ND - 5.20 ppb
20190.129 ppb351ND - 4.50 ppb

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
2014-05-154790-017-09254.80 ppb
2014-06-114790-017-13054.10 ppb
2014-06-184790-017-0935ND
2014-06-234790-017-1400ND
2014-07-034790-017-1005ND
2014-07-084790-017-1230ND
2014-07-164790-017-1135ND
2014-07-224790-017-1150ND
2014-07-294790-017-1145ND
2014-08-054790-017-1105ND
2014-08-124790-017-1115ND
2014-08-194790-017-1015ND
2014-08-264790-017-10505.40 ppb
2014-09-124790-017-1240ND
2014-09-224790-017-15354.20 ppb
2014-10-014790-017-1100ND
2014-10-094790-017-1305ND
2014-10-154790-017-1235ND
2014-10-224790-017-12454.10 ppb
2014-11-194790-017-1110ND
2014-11-244790-017-1010ND
2015-01-064790-017-1320ND
2015-01-144790-017-11354.80 ppb
2015-01-204790-017-1120ND
2015-01-264790-017-1440ND
2015-02-024790-017-11055.50 ppb
2015-02-094790-017-1510ND
2015-02-234790-017-1250ND
2015-03-024790-017-1430ND
2015-03-104790-017-1240ND
2015-03-184790-017-0835ND
2015-03-244790-017-1530ND
2015-04-014790-017-1015ND
2015-04-084790-017-1245ND
2015-04-164790-017-0920ND
2015-04-224790-017-1010ND
2015-04-284790-017-1020ND
2015-05-014790-017-1235ND
2015-06-034790-017-16204.40 ppb
2015-06-104790-017-11354.50 ppb
2015-06-174790-017-11054.70 ppb
2015-06-244790-017-0745ND
2015-07-014790-017-1225ND
2015-07-084790-017-1110ND
2015-07-154790-017-0805ND
2015-07-244790-017-1330ND
2015-07-284790-017-1015ND
2015-08-054790-017-0850ND
2015-08-124790-017-0745ND
2015-08-194790-017-1025ND
2015-08-254790-017-0820ND
2015-09-014790-017-0905ND
2015-09-114790-017-1050ND
2015-09-174790-017-0915ND
2015-09-244790-017-1040ND
2015-10-014790-017-0955ND
2015-10-074790-017-0915ND
2016-01-124790-017-12454.00 ppb
2016-03-024790-017-1330ND
2016-03-094790-017-1015ND
2016-03-154790-017-1225ND
2016-03-244790-017-0905ND
2016-03-294790-017-1105ND
2016-04-054790-017-11504.10 ppb
2016-04-134790-017-1415ND
2016-04-204790-017-0940ND
2016-04-264790-017-1010ND
2016-05-044790-017-0955ND
2016-05-104790-017-1145ND
2016-05-194790-017-0905ND
2016-05-254790-017-0930ND
2016-06-014790-017-10305.50 ppb
2016-06-084790-017-10354.00 ppb
2016-06-154790-017-13354.10 ppb
2016-06-224790-017-1135ND
2016-06-284790-017-1615ND
2016-07-064790-017-12105.10 ppb
2016-07-124790-017-10354.00 ppb
2016-07-204790-017-0915ND
2016-07-264790-017-0935ND
2016-08-024790-017-1120ND
2016-08-104790-017-0830ND
2016-08-164790-017-1150ND
2016-08-244790-017-0955ND
2016-09-014790-017-0850ND
2016-09-074790-017-0825ND
2016-09-144790-017-10354.40 ppb
2016-09-214790-017-10204.30 ppb
2016-09-274790-017-0815ND
2016-10-034790-017-1440ND
2016-10-124790-017-1255ND
2016-10-184790-017-0840ND
2016-11-034790-017-14154.00 ppb
2016-11-094790-017-1150ND
2016-11-164790-017-0905ND
2016-11-214790-017-0805ND
2016-12-154790-017-13304.50 ppb
2017-02-024790-017-1010ND
2017-02-074790-017-1105ND
2017-02-154790-017-1050ND
2017-03-074790-017-0955ND
2017-03-144790-017-0920ND
2017-03-224790-017-1335ND
2017-03-294790-017-1055ND
2017-04-044790-017-0815ND
2017-04-124790-017-0945ND
2017-04-184790-017-0745ND
2017-04-254790-017-0905ND
2017-05-024790-017-0915ND
2017-05-104790-017-10554.20 ppb
2017-05-174790-017-10504.70 ppb
2017-05-234790-017-09055.20 ppb
2017-06-014790-017-1015ND
2017-06-074790-017-0955ND
2017-06-144790-017-1050ND
2017-06-214790-017-0825ND
2017-06-284790-017-1135ND
2017-07-054790-017-0955ND
2017-07-114790-017-1130ND
2017-07-184790-017-0810ND
2017-07-254790-017-1050ND
2017-08-014790-017-1040ND
2017-08-084790-017-0820ND
2017-08-154790-017-0845ND
2017-08-234790-017-0820ND
2017-08-294790-017-0805ND
2017-09-054790-017-0910ND
2017-09-134790-017-0940ND
2017-09-194790-017-1105ND
2017-09-264790-017-0935ND
2017-10-054790-017-1030ND
2017-10-104790-017-0805ND
2017-10-174790-017-1125ND
2017-10-244790-017-0835ND
2017-11-074790-017-0915ND
2017-11-094790-017-1000ND
2017-11-214790-017-0835ND
2017-11-284790-017-0905ND
2017-12-074790-017-1155ND
2017-12-134790-017-1040ND
2017-12-184790-017-08054.10 ppb
2018-03-064790-017-1115ND
2018-04-114790-017-11104.90 ppb
2018-04-174790-017-1120ND
2018-04-244790-017-1045ND
2018-05-044790-017-1030ND
2018-05-094790-017-1005ND
2018-05-154790-017-1315ND
2018-05-244790-017-1350ND
2018-06-014790-017-0905ND
2018-06-064790-017-0900ND
2018-06-134790-017-1320ND
2018-06-214790-017-1030ND
2018-06-274790-017-0755ND
2018-07-034790-017-1355ND
2018-07-124790-017-1310ND
2018-07-184790-017-1045ND
2018-07-274790-017-11155.20 ppb
2018-08-014790-017-1010ND
2018-08-094790-017-1110ND
2018-08-164790-017-1110ND
2018-08-234790-017-0955ND
2018-08-284790-017-1335ND
2018-09-044790-017-1235ND
2018-09-124790-017-1255ND
2018-09-194790-017-0920ND
2018-09-264790-017-1405ND
2018-10-014790-017-1550ND
2018-11-064790-017-1555ND
2018-11-144790-017-1240ND
2018-11-204790-017-1345ND
2019-04-124790-017-1115ND
2019-04-184790-017-0940ND
2019-04-264790-017-0850ND
2019-05-014790-017-0925ND
2019-05-074790-017-0850ND
2019-05-144790-017-1355ND
2019-05-224790-017-1355ND
2019-05-294790-017-1025ND
2019-06-054790-017-1030ND
2019-06-134790-017-1025ND
2019-06-194790-017-1120ND
2019-06-264790-017-1030ND
2019-07-024790-017-1126ND
2019-07-104790-017-1045ND
2019-07-164790-017-1220ND
2019-07-244790-017-1120ND
2019-08-014790-017-1005ND
2019-08-074790-017-0800ND
2019-08-134790-017-1110ND
2019-08-214790-017-1300ND
2019-08-294790-017-0835ND
2019-09-044790-017-0920ND
2019-09-114790-017-0850ND
2019-09-204790-017-13354.50 ppb
2019-09-264790-017-0825ND
2019-10-014790-017-0920ND
2019-10-094790-017-0835ND
2019-10-164790-017-0925ND
2019-10-234790-017-1115ND
2019-10-304790-017-1338ND
2019-11-064790-017-0950ND
2019-11-144790-017-0850ND
2019-11-214790-017-1115ND
2019-11-264790-017-1200ND
2019-12-034790-017-1310ND