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EWG's Tap Water Database — 2019 UPDATE

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Perchlorate

Golden State Water Company (GSWC) - South Arcadia

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.

 

297

Samples

0

Samples exceeding legal limit (MCL)

2

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20120.0234 ppb471ND - 1.10 ppb
20130.124 ppb461ND - 5.70 ppb
2014ND530ND
2015ND540ND
2016ND490ND
2017ND480ND

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
2012-01-102706-002-0920ND
2012-01-102706-003-0930ND
2012-01-102706-004-0940ND
2012-01-102706-016-1015ND
2012-02-142706-002-1125ND
2012-02-142706-002-1135ND
2012-02-142706-003-1145ND
2012-02-142706-004-1125ND
2012-02-142706-016-1210ND
2012-03-132706-002-1107ND
2012-03-132706-003-1215ND
2012-03-132706-004-1156ND
2012-03-132706-016-1124ND
2012-04-102706-002-1133ND
2012-04-102706-003-1153ND
2012-04-102706-004-1039ND
2012-04-102706-016-1055ND
2012-05-082706-002-1210ND
2012-05-082706-003-1237ND
2012-05-082706-004-1123ND
2012-05-082706-016-11421.10 ppb
2012-05-159588-005-0915ND
2012-06-122706-002-1203ND
2012-06-122706-003-1116ND
2012-06-122706-016-1132ND
2012-07-162706-002-1139ND
2012-07-162706-003-1034ND
2012-07-162706-016-1100ND
2012-08-142706-002-1113ND
2012-08-142706-003-1140ND
2012-08-142706-016-1132ND
2012-08-169588-003-0945ND
2012-08-169588-006-0915ND
2012-08-169588-014-0850ND
2012-08-169588-015-0935ND
2012-09-112706-002-1105ND
2012-09-112706-003-1054ND
2012-09-112706-016-1129ND
2012-10-092706-002-1106ND
2012-10-092706-003-1140ND
2012-10-092706-016-1135ND
2012-11-132706-002-1130ND
2012-11-132706-003-1210ND
2012-11-132706-016-1137ND
2012-11-169588-002-1000ND
2012-12-102706-003-1128ND
2012-12-102706-016-1115ND
2013-01-082706-003-1200ND
2013-01-082706-016-1218ND
2013-02-122706-003-1424ND
2013-02-122706-016-1437ND
2013-02-282706-002-13055.70 ppb
2013-03-082706-002-1030ND
2013-03-122706-003-1142ND
2013-03-122706-016-1125ND
2013-04-092706-002-1115ND
2013-04-092706-003-1125ND
2013-04-092706-016-1145ND
2013-05-132706-002-1135ND
2013-05-132706-003-1149ND
2013-05-132706-004-1223ND
2013-05-132706-016-1213ND
2013-05-159588-004-1020ND
2013-05-159588-005-0950ND
2013-06-112706-002-1124ND
2013-06-112706-003-1131ND
2013-06-112706-004-1025ND
2013-06-112706-016-1051ND
2013-07-092706-002-1305ND
2013-07-092706-003-1227ND
2013-07-092706-004-1312ND
2013-07-092706-016-1244ND
2013-08-122706-002-1103ND
2013-08-122706-003-1016ND
2013-08-122706-004-1110ND
2013-08-122706-016-1040ND
2013-08-149588-003-1130ND
2013-08-149588-006-1200ND
2013-08-149588-014-1225ND
2013-08-289588-015-1135ND
2013-09-102706-002-1046ND
2013-09-102706-003-1004ND
2013-09-102706-016-1020ND
2013-10-082706-002-1107ND
2013-10-082706-003-1112ND
2013-10-082706-016-1135ND
2013-11-122706-002-1200ND
2013-11-122706-003-1151ND
2013-11-122706-016-1218ND
2013-11-149588-002-1055ND
2013-12-092706-002-1134ND
2013-12-092706-003-1054ND
2013-12-092706-016-1113ND
2014-01-132706-002-1204ND
2014-01-132706-003-1044ND
2014-01-132706-016-1113ND
2014-02-102706-002-1115ND
2014-02-102706-003-1024ND
2014-02-102706-004-1436ND
2014-02-102706-016-1053ND
2014-03-102706-002-1109ND
2014-03-102706-016-1041ND
2014-03-132706-003-1100ND
2014-03-132706-004-1120ND
2014-04-072706-002-1230ND
2014-04-072706-003-1243ND
2014-04-072706-004-1322ND
2014-04-072706-016-1245ND
2014-05-122706-002-1225ND
2014-05-122706-003-1325ND
2014-05-122706-004-1301ND
2014-05-142706-016-1148ND
2014-05-159588-004-1125ND
2014-06-092706-002-1127ND
2014-06-092706-003-1403ND
2014-06-092706-004-1100ND
2014-06-092706-016-1114ND
2014-06-249588-005-0940ND
2014-07-072706-002-1144ND
2014-07-072706-003-1152ND
2014-07-072706-004-1200ND
2014-07-072706-016-1134ND
2014-08-112706-002-1101ND
2014-08-112706-003-1035ND
2014-08-112706-004-1208ND
2014-08-112706-016-1144ND
2014-08-289588-003-1020ND
2014-08-289588-006-1100ND
2014-08-289588-014-1025ND
2014-09-082706-002-1024ND
2014-09-082706-003-1105ND
2014-09-082706-004-1005ND
2014-09-112706-016-1015ND
2014-10-132706-002-1030ND
2014-10-132706-003-1004ND
2014-10-132706-004-1215ND
2014-10-132706-016-1100ND
2014-11-059588-002-1035ND
2014-11-059588-015-0955ND
2014-11-102706-002-1111ND
2014-11-102706-004-1058ND
2014-11-102706-016-1151ND
2014-12-082706-002-0955ND
2014-12-082706-003-0940ND
2014-12-082706-004-1109ND
2014-12-082706-016-1029ND
2015-01-122706-002-1006ND
2015-01-122706-003-1104ND
2015-01-122706-004-1011ND
2015-01-122706-016-1020ND
2015-02-092706-002-1040ND
2015-02-092706-003-1007ND
2015-02-092706-004-1138ND
2015-02-092706-016-1129ND
2015-03-092706-016-1053ND
2015-03-102706-002-1050ND
2015-03-102706-003-1105ND
2015-03-102706-004-1035ND
2015-04-132706-002-1018ND
2015-04-132706-003-1121ND
2015-04-132706-004-1009ND
2015-04-132706-016-1031ND
2015-05-112706-002-1115ND
2015-05-112706-003-1034ND
2015-05-112706-004-1130ND
2015-05-112706-016-1059ND
2015-05-199588-004-0935ND
2015-05-199588-005-1045ND
2015-06-082706-002-1052ND
2015-06-082706-003-1103ND
2015-06-082706-004-1011ND
2015-06-092706-016-0930ND
2015-07-142706-002-0937ND
2015-07-142706-003-1010ND
2015-07-142706-004-0943ND
2015-07-142706-016-1030ND
2015-08-102706-002-1000ND
2015-08-102706-003-0946ND
2015-08-102706-004-1016ND
2015-08-102706-016-1008ND
2015-08-149588-003-1005ND
2015-08-149588-006-1045ND
2015-08-149588-014-1115ND
2015-09-082706-002-1100ND
2015-09-082706-003-1055ND
2015-09-082706-004-1010ND
2015-09-082706-016-1016ND
2015-10-122706-002-1000ND
2015-10-122706-004-0940ND
2015-10-122706-016-1017ND
2015-11-092706-002-0923ND
2015-11-092706-003-0917ND
2015-11-092706-004-1019ND
2015-11-092706-016-0931ND
2015-11-179588-002-0950ND
2015-11-179588-015-1015ND
2015-12-072706-002-1055ND
2015-12-072706-003-1105ND
2015-12-072706-004-1011ND
2015-12-072706-016-1021ND
2016-01-112706-002-1158ND
2016-01-112706-003-1201ND
2016-01-112706-016-1150ND
2016-02-082706-003-1120ND
2016-02-082706-016-1115ND
2016-03-082706-003-0920ND
2016-03-082706-004-0930ND
2016-03-082706-016-1106ND
2016-04-112706-003-1034ND
2016-04-112706-004-1442ND
2016-04-142706-016-1040ND
2016-05-102706-003-0935ND
2016-05-102706-004-0943ND
2016-05-102706-016-1007ND
2016-05-119588-004-1030ND
2016-05-119588-005-1105ND
2016-06-142710-003-1012ND
2016-06-142710-016-1042ND
2016-06-202710-002-1046ND
2016-06-202710-004-1035ND
2016-07-112710-002-1355ND
2016-07-112710-003-1345ND
2016-07-112710-004-1425ND
2016-07-142710-016-1204ND
2016-08-082710-002-1115ND
2016-08-082710-003-1051ND
2016-08-082710-004-1107ND
2016-08-082710-016-1140ND
2016-08-199588-003-1055ND
2016-08-199588-006-0920ND
2016-08-199588-014-0850ND
2016-09-122706-002-1105ND
2016-09-122706-003-1056ND
2016-09-122706-004-1142ND
2016-09-122706-016-1137ND
2016-10-102706-002-1106ND
2016-10-102706-003-1414ND
2016-10-102706-004-1028ND
2016-10-102706-016-1124ND
2016-11-072706-002-1002ND
2016-11-072706-003-0906ND
2016-11-072706-004-0930ND
2016-11-072706-016-0935ND
2016-11-179588-002-1005ND
2016-11-179588-015-1100ND
2016-12-122706-002-1210ND
2016-12-122706-003-1200ND
2016-12-122706-004-1233ND
2016-12-122706-016-1308ND
2017-01-099590-003-1415ND
2017-01-099590-004-1033ND
2017-01-099590-016-1115ND
2017-02-149590-002-1018ND
2017-02-149590-003-1010ND
2017-02-149590-004-0950ND
2017-02-149590-016-1026ND
2017-03-139590-016-1036ND
2017-03-169590-002-1130ND
2017-03-169590-003-1120ND
2017-03-249590-004-1511ND
2017-04-109590-002-1212ND
2017-04-109590-003-1221ND
2017-04-109590-004-1324ND
2017-04-109590-016-1255ND
2017-05-089590-003-0911ND
2017-05-089590-004-0903ND
2017-05-089590-016-0945ND
2017-05-169588-004-1020ND
2017-05-169588-005-1040ND
2017-07-109590-003-1255ND
2017-07-109590-004-1300ND
2017-07-109590-016-1240ND
2017-08-079590-003-1342ND
2017-08-079590-004-1328ND
2017-08-079590-016-1426ND
2017-08-109588-003-1000ND
2017-08-109588-006-1035ND
2017-08-109588-014-1055ND
2017-08-239590-002-1200ND
2017-09-119590-002-1246ND
2017-09-119590-003-1233ND
2017-09-119590-004-1258ND
2017-09-119590-016-1319ND
2017-10-099590-002-1220ND
2017-10-099590-003-1325ND
2017-10-099590-004-1205ND
2017-10-099590-016-1308ND
2017-11-139590-002-1053ND
2017-11-139590-003-1107ND
2017-11-139590-004-1218ND
2017-11-139590-016-1152ND
2017-11-299588-002-0945ND
2017-11-299588-015-1015ND
2017-12-129590-002-1055ND
2017-12-129590-003-1110ND
2017-12-129590-004-1045ND
2017-12-129590-016-1135ND