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EWG's Tap Water Database — 2021 UPDATE

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Chloroform

Park WC - Lynwood

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

 

111

Samples

0

Samples exceeding legal limit (MCL)

77

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20145.51 ppb2013ND - 16.0 ppb
20154.43 ppb1610ND - 13.0 ppb
20163.54 ppb2014ND - 11.0 ppb
20178.39 ppb1816ND - 31.0 ppb
20181.95 ppb1712ND - 6.00 ppb
20190.965 ppb2012ND - 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
2014-01-169588-800-1034ND
2014-01-169588-801-10581.10 ppb
2014-01-169588-802-11239.60 ppb
2014-01-169588-803-111410.00 ppb
2014-02-139588-005-1010ND
2014-04-179588-800-10001.30 ppb
2014-04-179588-801-10071.50 ppb
2014-04-179588-802-101715.0 ppb
2014-04-179588-803-102513.0 ppb
2014-05-299588-005-1130ND
2014-07-109588-800-1045ND
2014-07-109588-801-1055ND
2014-07-109588-802-112012.0 ppb
2014-07-109588-803-111016.0 ppb
2014-08-219588-005-1330ND
2014-10-169588-800-09451.30 ppb
2014-10-169588-801-10001.30 ppb
2014-10-169588-802-101512.0 ppb
2014-10-169588-803-102516.0 ppb
2014-11-129588-005-1315ND
2015-01-229588-800-0945ND
2015-01-229588-801-09581.30 ppb
2015-01-229588-802-10157.80 ppb
2015-01-229588-803-10459.20 ppb
2015-02-269588-005-1230ND
2015-04-179588-800-07221.10 ppb
2015-04-179588-801-07421.20 ppb
2015-04-179588-802-075913.0 ppb
2015-04-179588-803-081011.0 ppb
2015-05-089588-005-1150ND
2015-07-169588-800-1140ND
2015-07-169588-801-11551.20 ppb
2015-07-169588-802-121012.0 ppb
2015-07-169588-803-122513.0 ppb
2015-08-059588-005-0915ND
2015-11-199588-005-1035ND
2016-02-049588-800-1055ND
2016-02-049588-801-11101.000 ppb
2016-02-049588-802-11455.20 ppb
2016-02-049588-803-11305.00 ppb
2016-04-149588-005-0945ND
2016-04-229588-800-08551.30 ppb
2016-04-229588-801-09051.50 ppb
2016-04-229588-802-092011.0 ppb
2016-04-229588-803-09304.20 ppb
2016-05-259588-005-1030ND
2016-07-289588-800-10302.10 ppb
2016-07-289588-801-10403.80 ppb
2016-07-289588-802-1050ND
2016-07-289588-803-11054.20 ppb
2016-08-049588-005-1210ND
2016-10-279588-800-12008.50 ppb
2016-10-279588-801-12142.70 ppb
2016-10-279588-802-12309.30 ppb
2016-10-279588-803-124511.0 ppb
2016-11-159588-005-0925ND
2017-01-139588-800-10108.80 ppb
2017-01-139588-801-10207.70 ppb
2017-01-139588-802-10509.00 ppb
2017-01-139588-803-10307.10 ppb
2017-02-239588-005-1315ND
2017-04-139588-800-093031.0 ppb
2017-04-139588-801-095118.0 ppb
2017-04-139588-802-100831.0 ppb
2017-04-139588-803-102521.0 ppb
2017-07-209588-800-10141.10 ppb
2017-07-209588-801-10251.20 ppb
2017-07-209588-802-10401.40 ppb
2017-07-209588-803-11401.50 ppb
2017-10-129588-800-11251.10 ppb
2017-10-129588-801-11401.20 ppb
2017-10-129588-802-11553.10 ppb
2017-10-129588-803-12106.80 ppb
2017-11-309588-005-0945ND
2018-01-189588-800-11351.30 ppb
2018-01-189588-802-12003.00 ppb
2018-01-199588-803-09453.40 ppb
2018-01-299588-801-10501.50 ppb
2018-01-299588-803-11154.80 ppb
2018-02-279588-005-1230ND
2018-04-269588-800-09451.40 ppb
2018-04-269588-801-10003.30 ppb
2018-04-269588-802-10306.00 ppb
2018-04-269588-803-10154.30 ppb
2018-05-119588-005-1000ND
2018-08-169588-005-0715ND
2018-10-119588-800-07551.30 ppb
2018-10-119588-801-08051.50 ppb
2018-10-119588-802-0830ND
2018-10-119588-803-08201.40 ppb
2018-11-089588-005-1030ND
2019-01-089588-800-10561.50 ppb
2019-01-089588-801-10051.80 ppb
2019-01-089588-802-0856ND
2019-01-089588-803-08141.50 ppb
2019-02-139588-005-0930ND
2019-04-099588-800-11001.40 ppb
2019-04-099588-801-11151.80 ppb
2019-04-099588-802-1130ND
2019-04-099588-803-11451.60 ppb
2019-05-159588-005-0930ND
2019-07-109588-800-09101.20 ppb
2019-07-109588-801-09251.40 ppb
2019-07-109588-802-1005ND
2019-07-109588-803-09401.80 ppb
2019-08-139588-005-0945ND
2019-10-089588-800-11451.60 ppb
2019-10-089588-801-12001.60 ppb
2019-10-089588-802-1215ND
2019-10-089588-803-12302.10 ppb
2019-11-129588-005-1450ND