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EWG's Tap Water Database — 2021 UPDATE

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Chloroform

Golden State WC - Placentia

Chloroform, one of the total trihalomethanes (TTHMs), is formed when chlorine or other disinfectants are used to treat drinking water. Chloroform and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Read More.

In addition to tap water disinfection, chloroform pollution in the environment also comes from industrial discharges from pulp and paper mills, and from urban wastewater effluent. Human studies show that chloroform damages the kidneys, liver and central nervous system. In animals, chloroform causes infertility, birth defects and cancer.

Click here to read more about disinfection byproducts.

MORE ABOUT THIS CONTAMINANT

 

194

Samples

0

Samples exceeding legal limit (MCL)

124

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2013N/A00N/A
20146.35 ppb2314ND - 14.0 ppb
20153.42 ppb3116ND - 11.0 ppb
20161.45 ppb4326ND - 4.80 ppb
20172.35 ppb3725ND - 7.20 ppb
20181.78 ppb3021ND - 4.40 ppb
20191.75 ppb3022ND - 4.70 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 0.4 ppb

The EWG Health Guideline of 0.4 ppb for chloroform was proposed in 2018 by the California Office of Environmental Health Hazard Assessment as a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.

ppb = parts per billion

All test results

Date Lab ID Result
2014-01-234417-001-0920ND
2014-01-234417-002-0935ND
2014-01-234417-005-1000ND
2014-01-312706-801-12008.90 ppb
2014-01-312706-802-12208.70 ppb
2014-01-312706-803-12409.30 ppb
2014-01-312706-804-1300ND
2014-03-104417-003-1140ND
2014-04-082706-801-08307.70 ppb
2014-04-082706-802-09007.60 ppb
2014-04-082706-803-09157.90 ppb
2014-04-082706-804-0945ND
2014-04-164417-001-0940ND
2014-04-164417-002-0950ND
2014-04-164417-005-1015ND
2014-07-082706-801-083012.0 ppb
2014-07-082706-802-080012.0 ppb
2014-07-082706-803-073012.0 ppb
2014-07-082706-804-06457.90 ppb
2014-10-072706-801-092312.0 ppb
2014-10-072706-802-095014.0 ppb
2014-10-072706-803-100814.0 ppb
2014-10-072706-804-090012.0 ppb
2015-01-132706-801-09487.70 ppb
2015-01-132706-802-10097.60 ppb
2015-01-132706-803-10267.60 ppb
2015-01-132706-804-09252.90 ppb
2015-01-204417-001-0940ND
2015-01-204417-005-1015ND
2015-03-094417-003-10101.60 ppb
2015-03-254417-002-1135ND
2015-04-142706-801-09059.40 ppb
2015-04-142706-802-09209.80 ppb
2015-04-142706-803-094510.00 ppb
2015-04-142706-804-0845ND
2015-04-204417-002-0905ND
2015-04-204417-003-08451.80 ppb
2015-04-204417-005-0935ND
2015-06-154417-001-1025ND
2015-07-064417-001-0935ND
2015-07-064417-002-0920ND
2015-07-064417-005-1000ND
2015-07-152706-801-101611.0 ppb
2015-07-152706-802-104011.0 ppb
2015-07-152706-803-110011.0 ppb
2015-07-152706-804-0955ND
2015-10-132706-801-09584.40 ppb
2015-10-132706-802-10204.60 ppb
2015-10-132706-803-10454.40 ppb
2015-10-132706-804-0934ND
2015-10-204417-001-0955ND
2015-10-204417-002-0940ND
2015-10-204417-003-09051.30 ppb
2015-10-204417-005-1020ND
2016-01-132706-801-08453.30 ppb
2016-01-132706-802-08104.80 ppb
2016-01-132706-803-07304.80 ppb
2016-01-132706-804-06451.10 ppb
2016-01-194417-001-1040ND
2016-01-194417-002-1030ND
2016-01-194417-003-11001.10 ppb
2016-01-194417-005-1130ND
2016-04-122706-801-09592.00 ppb
2016-04-122706-802-10183.20 ppb
2016-04-122706-803-10423.10 ppb
2016-04-122706-804-0931ND
2016-04-194417-001-0940ND
2016-04-194417-002-0950ND
2016-04-194417-003-09201.10 ppb
2016-04-194417-005-1030ND
2016-05-174417-001-0855ND
2016-05-174417-002-0805ND
2016-05-174417-003-08251.000 ppb
2016-06-084417-003-10501.30 ppb
2016-07-122706-801-09473.80 ppb
2016-07-122706-802-10064.00 ppb
2016-07-122706-803-10354.40 ppb
2016-07-122706-804-09101.10 ppb
2016-07-184417-001-0930ND
2016-07-184417-002-0910ND
2016-07-184417-003-08501.20 ppb
2016-07-184417-005-1010ND
2016-07-274417-003-11101.10 ppb
2016-08-154417-001-0830ND
2016-08-154417-001-0840ND
2016-08-154417-003-08151.10 ppb
2016-09-214417-003-09551.000 ppb
2016-10-112706-801-10114.50 ppb
2016-10-112706-802-10304.50 ppb
2016-10-112706-803-10524.60 ppb
2016-10-112706-804-09451.10 ppb
2016-10-174417-001-1025ND
2016-10-174417-002-1035ND
2016-10-174417-003-10051.000 ppb
2016-10-174417-005-1050ND
2016-11-144417-003-10001.000 ppb
2016-12-054417-003-10101.000 ppb
2017-01-104417-001-1030ND
2017-01-104417-002-1020ND
2017-01-104417-005-1040ND
2017-01-119590-801-06502.70 ppb
2017-01-119590-802-07376.30 ppb
2017-01-119590-803-07186.40 ppb
2017-01-119590-804-06301.000 ppb
2017-01-244417-003-11001.20 ppb
2017-02-024417-003-09051.10 ppb
2017-03-074417-003-08501.20 ppb
2017-04-119590-801-10536.10 ppb
2017-04-119590-802-11177.20 ppb
2017-04-119590-803-11436.90 ppb
2017-04-119590-804-0951ND
2017-04-274417-001-0915ND
2017-04-274417-002-0905ND
2017-04-274417-003-08451.10 ppb
2017-05-014417-005-1240ND
2017-05-154417-003-10301.20 ppb
2017-06-204417-003-11051.20 ppb
2017-07-119590-801-10273.60 ppb
2017-07-119590-802-10573.70 ppb
2017-07-119590-803-11273.70 ppb
2017-07-119590-804-09411.80 ppb
2017-07-274417-001-1010ND
2017-07-274417-002-10251.20 ppb
2017-07-274417-005-1045ND
2017-08-314417-003-08451.10 ppb
2017-09-054417-003-11201.10 ppb
2017-10-054417-001-1020ND
2017-10-054417-002-1010ND
2017-10-054417-003-09301.10 ppb
2017-10-054417-005-1035ND
2017-10-109590-801-12356.50 ppb
2017-10-109590-802-12536.40 ppb
2017-10-109590-803-13157.20 ppb
2017-10-109590-804-12136.00 ppb
2018-01-099590-801-08353.20 ppb
2018-01-099590-802-08552.60 ppb
2018-01-099590-803-09252.80 ppb
2018-01-099590-804-08052.80 ppb
2018-01-294417-001-08501.20 ppb
2018-01-294417-002-09001.000 ppb
2018-01-294417-005-0920ND
2018-02-054417-003-0930ND
2018-04-109590-801-10203.50 ppb
2018-04-109590-802-10404.40 ppb
2018-04-109590-803-11054.40 ppb
2018-04-109590-804-09401.30 ppb
2018-04-244417-001-12251.10 ppb
2018-04-244417-002-1235ND
2018-04-244417-003-1100ND
2018-04-244417-003-1120ND
2018-07-024417-001-10201.000 ppb
2018-07-024417-002-1045ND
2018-07-024417-003-08501.10 ppb
2018-07-109590-801-10113.10 ppb
2018-07-109590-802-10353.70 ppb
2018-07-109590-803-10572.90 ppb
2018-07-109590-804-09361.40 ppb
2018-10-084417-001-1035ND
2018-10-084417-002-1045ND
2018-10-084417-003-10101.10 ppb
2018-10-099590-801-09523.40 ppb
2018-10-099590-802-10113.50 ppb
2018-10-099590-803-10303.80 ppb
2018-10-099590-804-0925ND
2019-01-089590-801-0900ND
2019-01-089590-802-09304.10 ppb
2019-01-089590-803-1010ND
2019-01-089590-804-11001.10 ppb
2019-01-104417-001-10401.000 ppb
2019-01-104417-002-1050ND
2019-01-104417-003-10001.30 ppb
2019-01-104417-005-1110ND
2019-04-099590-801-10283.60 ppb
2019-04-099590-802-11044.70 ppb
2019-04-099590-803-11354.00 ppb
2019-04-099590-804-09521.40 ppb
2019-04-294417-001-0925ND
2019-04-294417-002-0940ND
2019-04-294417-003-08401.70 ppb
2019-05-064417-003-12351.80 ppb
2019-07-099590-801-12252.80 ppb
2019-07-099590-802-12353.40 ppb
2019-07-099590-803-13153.70 ppb
2019-07-099590-804-11251.20 ppb
2019-07-164417-001-09401.000 ppb
2019-07-164417-002-1005ND
2019-08-064417-003-13251.50 ppb
2019-10-089590-801-08003.40 ppb
2019-10-089590-802-07253.40 ppb
2019-10-089590-803-06553.50 ppb
2019-10-089590-804-08301.20 ppb
2019-10-244417-002-1055ND
2019-10-244417-003-10151.40 ppb
2019-11-254417-001-09001.20 ppb