Know Your Environment. Protect Your Health.

Chloroform

Westminster Water Supply Corporation

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.

 

25

Samples

0

Samples exceeding legal limit (MCL)

4

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.260 ppb41ND - 1.04 ppb
2019ND50ND
20200.283 ppb41ND - 1.13 ppb
2021ND40ND
20220.635 ppb42ND - 1.48 ppb
2023ND40ND

ppb = parts per billion

State, National, and Health Guidelines for Drinking Water

EWG Health Guideline: 0.4 ppb

The EWG Health Guideline of 0.4 ppb for chloroform was based on the California Office of Environmental Health Hazard Assessment's public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer and harm to fetal growth and development.

ppb = parts per billion

All test results

Date Lab ID Result
2018-06-20Q1824691013ND
2018-06-20Q18246910161.04 ppb
2018-06-20Q1824691012ND
2018-08-23Q1834033004ND
2019-02-12Q1906728001ND
2019-02-12Q1906728003ND
2019-02-12Q1906728005ND
2019-05-14Q1924859004ND
2019-05-14Q1924859008ND
2020-08-05Q2030915012ND
2020-08-05Q2030915005ND
2020-08-05Q20309150031.13 ppb
2020-08-05Q2030915001ND
2021-09-28Q2126460001ND
2021-12-06Q2133784016ND
2021-12-06Q2133784018ND
2021-12-06Q2133784020ND
2022-05-11Q2214188003ND
2022-05-11Q22141880051.48 ppb
2022-05-11Q2214188007ND
2022-05-11Q22141880141.06 ppb
2023-08-15Q2334073002ND
2023-08-15Q2334073004ND
2023-08-15Q2334073006ND
2023-08-15Q2334073010ND