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EWG's Tap Water Database — 2021 UPDATE

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Monochloroacetic acid

California Water Service Company - Westlake

Monochloroacetic acid, one of the group of five haloacetic acids regulated by federal standards, is formed when chlorine or other disinfectants are used to treat drinking water. Haloacetic acids and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Click here to read more about disinfection byproducts.

MORE ABOUT THIS CONTAMINANT

 

94

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20140.821 ppb143ND - 4.90 ppb
2015ND160ND
2016ND160ND
2017ND160ND
2018ND160ND
2019ND160ND

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 53 ppb

The EWG Health Guideline of 53 ppb for monochloroacetic acid was proposed in 2020 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 system toxicity.

ppb = parts per billion

All test results

Date Lab ID Result
2014-03-195810-002-1410ND
2014-03-245810-005-1420ND
2014-06-165810-005-10203.90 ppb
2014-06-165810-004-10402.70 ppb
2014-06-165810-003-10004.90 ppb
2014-06-165810-002-0941ND
2014-09-155810-005-1045ND
2014-09-155810-004-1103ND
2014-09-155810-003-1027ND
2014-09-155810-002-1009ND
2014-12-155810-005-1056ND
2014-12-155810-004-1114ND
2014-12-155810-003-1038ND
2014-12-155810-002-1020ND
2015-03-175810-005-1105ND
2015-03-175810-003-1047ND
2015-03-175810-004-1123ND
2015-03-175810-002-1029ND
2015-06-165810-005-1025ND
2015-06-165810-004-1043ND
2015-06-165810-002-0949ND
2015-06-165810-003-1007ND
2015-09-215810-003-1027ND
2015-09-215810-002-1019ND
2015-09-215810-005-1045ND
2015-09-215810-004-1103ND
2015-12-215810-003-0937ND
2015-12-215810-002-0919ND
2015-12-215810-004-0955ND
2015-12-215810-005-1013ND
2016-03-215810-002-0937ND
2016-03-215810-004-1032ND
2016-03-215810-003-0956ND
2016-03-215810-005-1014ND
2016-06-235810-005-1050ND
2016-06-235810-004-1115ND
2016-06-235810-003-1020ND
2016-06-235810-002-1005ND
2016-09-195810-005-1015ND
2016-09-195810-004-1033ND
2016-09-195810-002-0939ND
2016-09-195810-003-0957ND
2016-12-205810-003-0939ND
2016-12-205810-005-0957ND
2016-12-205810-004-1015ND
2016-12-205810-002-0921ND
2017-03-205810-003-1008ND
2017-03-205810-004-1044ND
2017-03-205810-002-0950ND
2017-03-205810-005-1026ND
2017-06-205810-004-1006ND
2017-06-205810-003-1151ND
2017-06-205810-002-1138ND
2017-06-205810-005-1211ND
2017-09-195810-005-0927ND
2017-09-195810-003-0909ND
2017-09-195810-004-0945ND
2017-09-265810-002-0850ND
2017-12-185810-004-0959ND
2017-12-185810-003-0924ND
2017-12-185810-005-0941ND
2017-12-185810-002-0906ND
2018-03-195810-004-1041ND
2018-03-195810-005-1023ND
2018-03-195810-002-0947ND
2018-03-195810-003-1005ND
2018-06-185810-003-1007ND
2018-06-185810-005-1025ND
2018-06-185810-004-1043ND
2018-06-185810-002-0949ND
2018-09-175810-004-1115ND
2018-09-175810-005-1055ND
2018-09-175810-002-1005ND
2018-09-175810-003-1031ND
2018-12-175810-004-1051ND
2018-12-175810-005-1031ND
2018-12-175810-003-1007ND
2018-12-175810-002-0949ND
2019-03-185810-005-1108ND
2019-03-185810-003-1046ND
2019-03-185810-002-1020ND
2019-03-185810-004-1136ND
2019-06-185810-004-1031ND
2019-06-185810-005-1013ND
2019-06-185810-003-0955ND
2019-06-185810-002-0937ND
2019-09-165810-005-1210ND
2019-09-165810-002-1248ND
2019-09-165810-003-1230ND
2019-09-165810-004-1000ND
2019-12-165810-005-1148ND
2019-12-165810-003-1208ND
2019-12-165810-004-0956ND
2019-12-165810-002-1224ND