Know Your Environment. Protect Your Health.

Chloroform

Gonzales County 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.

 

72

Samples

0

Samples exceeding legal limit (MCL)

2

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2018ND120ND
20190.490 ppb101ND - 4.90 ppb
20200.0933 ppb151ND - 1.40 ppb
2021ND130ND
2022ND100ND
2023ND120ND

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
2018-02-08AE12981ND
2018-02-08AE12980ND
2018-02-08AE13037ND
2018-03-12AE17842ND
2018-03-12AE17882ND
2018-03-12AE17864ND
2018-05-03AE25012ND
2018-05-03AE25055ND
2018-08-16AE37317ND
2018-08-16AE37318ND
2018-12-12AE48632ND
2018-12-12AE48633ND
2019-01-09AE49237ND
2019-01-09AE49241ND
2019-03-05AE57116ND
2019-03-05AE571174.90 ppb
2019-04-02AE60853ND
2019-04-02AE60858ND
2019-07-12AE74352ND
2019-07-12AE74353ND
2019-10-14AE86437ND
2019-10-14AE86439ND
2020-01-21AE94302ND
2020-01-21AE94304ND
2020-01-21AE943311.40 ppb
2020-01-21AE94371ND
2020-03-10AF02001ND
2020-03-10AF02005ND
2020-04-13AF06460ND
2020-04-13AF06461ND
2020-04-13AF06483ND
2020-08-24AF24854ND
2020-08-24AF24855ND
2020-08-24AF24889ND
2020-11-13AF34899ND
2020-11-13AF34874ND
2020-11-13AF34876ND
2021-01-13AF39103ND
2021-01-13AF39104ND
2021-01-13AF39134ND
2021-01-13AF39136ND
2021-01-13AF39142ND
2021-04-01AF48828ND
2021-04-01AF48829ND
2021-04-01AF48848ND
2021-08-18AF66871ND
2021-08-18AF66912ND
2021-08-18AF66873ND
2021-10-05AF72258ND
2021-10-05AF72260ND
2022-02-09AF83956ND
2022-02-09AF83957ND
2022-02-09AF84022ND
2022-04-20AF93870ND
2022-04-20AF93902ND
2022-04-20AF93871ND
2022-04-20AF93900ND
2022-09-30AG15663ND
2022-09-30AG15664ND
2022-12-09AG21487ND
2023-03-15AG33167ND
2023-03-15AG33168ND
2023-03-29AG34756ND
2023-06-21AG45238ND
2023-06-21Q2324807003ND
2023-06-21Q2324807001ND
2023-06-21AG45313ND
2023-06-21AG45239ND
2023-09-11AG55537ND
2023-09-11AG55539ND
2023-11-28AG64588ND
2023-11-28AG64590ND