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EWG's Tap Water Database — 2021 UPDATE

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Chloroform

Cal-am Water Company - Duarte

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

 

165

Samples

0

Samples exceeding legal limit (MCL)

10

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2013N/A00N/A
20140.113 ppb303ND - 1.20 ppb
20150.113 ppb303ND - 1.20 ppb
2016ND310ND
20170.0458 ppb241ND - 1.10 ppb
20180.0783 ppb231ND - 1.80 ppb
20190.122 ppb272ND - 2.10 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
2014-01-319588-800-0755ND
2014-01-319588-801-08201.10 ppb
2014-01-319588-802-0810ND
2014-01-319588-803-07401.10 ppb
2014-03-109588-004-1140ND
2014-04-309588-800-09101.20 ppb
2014-04-309588-801-0935ND
2014-04-309588-802-0925ND
2014-04-309588-803-0800ND
2014-06-231225-002-1300ND
2014-06-231225-003-1110ND
2014-06-231225-007-1040ND
2014-06-231225-008-1235ND
2014-06-231225-009-1135ND
2014-06-231225-010-1330ND
2014-07-319588-800-1145ND
2014-07-319588-801-1200ND
2014-07-319588-802-1210ND
2014-07-319588-803-1125ND
2014-09-039588-002-1055ND
2014-09-039588-003-1215ND
2014-09-039588-007-1240ND
2014-09-039588-008-1120ND
2014-09-039588-010-1225ND
2014-10-319588-800-0935ND
2014-10-319588-801-0955ND
2014-10-319588-802-0945ND
2014-10-319588-803-1030ND
2014-12-039588-009-1100ND
2014-12-039588-019-1020ND
2015-01-299588-800-0820ND
2015-01-299588-801-0840ND
2015-01-299588-802-0830ND
2015-01-299588-803-07301.20 ppb
2015-04-309588-800-0750ND
2015-04-309588-801-0730ND
2015-04-309588-802-0740ND
2015-04-309588-803-1045ND
2015-07-319588-800-08301.10 ppb
2015-07-319588-801-0850ND
2015-07-319588-802-0840ND
2015-07-319588-803-0730ND
2015-09-089588-002-1200ND
2015-09-089588-003-1140ND
2015-09-089588-007-1215ND
2015-09-089588-008-1120ND
2015-09-089588-010-1110ND
2015-09-281225-003-1050ND
2015-09-281225-007-1200ND
2015-09-281225-008-1330ND
2015-09-281225-009-1345ND
2015-09-281225-010-0945ND
2015-10-141225-002-1205ND
2015-10-141225-019-0945ND
2015-10-299588-800-0840ND
2015-10-299588-801-0900ND
2015-10-299588-802-0850ND
2015-10-299588-803-07301.10 ppb
2015-12-079588-009-1130ND
2015-12-079588-019-1040ND
2016-01-289588-800-0840ND
2016-01-289588-801-0900ND
2016-01-289588-802-0850ND
2016-01-289588-803-0740ND
2016-04-289588-800-0850ND
2016-04-289588-801-0915ND
2016-04-289588-802-0905ND
2016-04-289588-803-0755ND
2016-06-201225-008-1145ND
2016-06-201225-010-1135ND
2016-06-201225-019-1115ND
2016-07-201225-002-1110ND
2016-07-201225-003-1000ND
2016-07-201225-007-0930ND
2016-07-201225-009-1030ND
2016-07-289588-800-0840ND
2016-07-289588-801-0900ND
2016-07-289588-802-0840ND
2016-07-289588-803-0730ND
2016-09-079588-002-1330ND
2016-09-079588-003-1305ND
2016-09-079588-007-1245ND
2016-09-079588-008-1345ND
2016-09-079588-010-1315ND
2016-09-121225-019-0850ND
2016-10-289588-800-0835ND
2016-10-289588-801-0855ND
2016-10-289588-802-0845ND
2016-10-289588-803-0735ND
2016-12-059588-009-1135ND
2016-12-059588-019-1105ND
2017-01-309588-800-0830ND
2017-01-309588-801-0850ND
2017-01-309588-802-0840ND
2017-01-309588-803-0730ND
2017-04-289588-800-0840ND
2017-04-289588-801-0900ND
2017-04-289588-802-0850ND
2017-04-289588-803-0730ND
2017-07-251225-009-1210ND
2017-07-319588-800-1605ND
2017-07-319588-801-1535ND
2017-07-319588-802-1550ND
2017-07-319588-803-1515ND
2017-09-209588-002-1150ND
2017-09-209588-007-1100ND
2017-09-209588-008-1125ND
2017-09-209588-010-1210ND
2017-09-289588-003-0905ND
2017-10-319588-800-0855ND
2017-10-319588-801-0925ND
2017-10-319588-802-0905ND
2017-10-319588-803-07401.10 ppb
2017-12-059588-009-1030ND
2017-12-059588-019-1000ND
2018-02-209588-800-0815ND
2018-02-209588-801-0840ND
2018-02-209588-802-0830ND
2018-02-209588-803-0740ND
2018-04-279588-800-0820ND
2018-04-279588-801-0840ND
2018-04-279588-802-0830ND
2018-04-279588-803-0720ND
2018-07-101225-009-0940ND
2018-07-309588-800-0835ND
2018-07-309588-801-0835ND
2018-07-309588-802-09001.80 ppb
2018-07-309588-803-0845ND
2018-09-209588-002-1300ND
2018-09-209588-007-1215ND
2018-09-209588-008-1240ND
2018-09-209588-010-1325ND
2018-10-309588-800-0900ND
2018-10-309588-801-0920ND
2018-10-309588-802-0910ND
2018-10-309588-803-0800ND
2018-12-189588-009-1150ND
2018-12-189588-019-1055ND
2019-01-299588-800-0900ND
2019-01-299588-801-0925ND
2019-01-299588-802-09151.20 ppb
2019-01-299588-803-0800ND
2019-02-069590-022-1230ND
2019-03-199588-003-1135ND
2019-04-299588-800-0850ND
2019-04-299588-801-0925ND
2019-04-299588-802-09052.10 ppb
2019-04-299588-803-0745ND
2019-05-139588-022-1310ND
2019-07-299588-800-0800ND
2019-07-299588-801-0820ND
2019-07-299588-802-0810ND
2019-07-299588-803-0700ND
2019-08-079588-002-1250ND
2019-08-079588-007-1145ND
2019-08-079588-008-1220ND
2019-08-079588-009-1210ND
2019-08-079588-010-1305ND
2019-08-079588-019-1115ND
2019-08-079588-022-1325ND
2019-10-299588-800-0820ND
2019-10-299588-801-0845ND
2019-10-299588-802-0835ND
2019-10-299588-803-0720ND
2019-11-199588-022-1040ND