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EWG's Tap Water Database — 2021 UPDATE

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Chloroform

Riviera WCID

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.

 

12

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2014ND10ND
2015ND30ND
2016ND20ND
2017ND20ND
2018ND20ND
2019ND20ND

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
2014-06-11AC56585ND
2015-02-24AC81717ND
2015-02-24AC81715ND
2015-05-13AC91816ND
2016-02-23AD25046ND
2016-05-24AD37961ND
2017-03-08AD74069ND
2017-06-27AD87915ND
2018-03-06AE16984ND
2018-08-15AE37183ND
2019-03-14AE58439ND
2019-07-16AE74616ND