Menu

EWG's Tap Water Database — 2021 UPDATE

Donate

Chloroform

Liberty Utilities

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.

 

38

Samples

0

Samples exceeding legal limit (MCL)

24

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20141.26 ppb1511ND - 3.29 ppb
20151.000 ppb42ND - 2.00 ppb
20161.63 ppb43ND - 3.30 ppb
20170.219 ppb72ND - 0.770 ppb
20181.50 ppb43ND - 3.20 ppb
20191.28 ppb43ND - 2.20 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
2014-02-17140510037011.60 ppb
2014-02-17140510036011.30 ppb
2014-02-17140510034011.20 ppb
2014-02-1714051003501ND
2014-05-05141280070021.50 ppb
2014-05-05141280071021.40 ppb
2014-05-0514128007202ND
2014-05-0514128007302ND
2014-09-09142540039021.80 ppb
2014-09-09142540040022.80 ppb
2014-09-09142540037022.00 ppb
2014-09-09142540038021.10 ppb
2014-10-2214296010401ND
2014-10-22142960106010.840 ppb
2014-10-22142960105013.29 ppb
2015-04-21151130119022.00 ppb
2015-04-2115113011802ND
2015-07-22152040004022.00 ppb
2015-07-2215204000502ND
2016-04-2116113001502ND
2016-04-21161130016021.60 ppb
2016-08-15162300004021.60 ppb
2016-08-15162300005023.30 ppb
2017-04-1717109000502ND
2017-04-1717109000402ND
2017-08-1517229003702ND
2017-08-1517229003802ND
2017-10-2417298004901ND
2017-10-24172980050010.760 ppb
2017-10-24172980048010.770 ppb
2018-05-2118144009002ND
2018-05-21181440089021.70 ppb
2018-07-17182000027023.20 ppb
2018-07-17182000026021.10 ppb
2019-04-17191080048021.80 ppb
2019-04-17191080047021.10 ppb
2019-07-02191840033012.20 ppb
2019-07-0219184001401ND