Chloroform

City of Refugio

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

Samples

Samples exceeding legal limit (MCL)

Samples exceeding
health guidelines

Testing results - average by year

Year	Average result	Samples taken	Range of results
2014	ND	2	ND
2015	ND	2	ND
2016	ND	7	ND
2017	ND	3	ND
2018	ND	2	ND
2019	ND	3	ND

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
2014-04-02	AC49026	ND
2014-09-09	AC66267	ND
2015-04-21	AC89079	ND
2015-09-09	AD06184	ND
2016-03-14	AD28500	ND
2016-03-14	AD28502	ND
2016-07-18	AD44577	ND
2016-07-18	AD44575	ND
2016-07-18	AD44534	ND
2016-10-26	AD54823	ND
2016-10-26	AD54833	ND
2017-04-04	AD78311	ND
2017-04-04	AD78329	ND
2017-07-14	AD89493	ND
2018-02-20	AE14479	ND
2018-06-11	AE29233	ND
2019-06-10	AE69713	ND
2019-06-10	AE69760	ND
2019-08-15	AE78928	ND