Know Your Environment. Protect Your Health.

Chloroform

Ransom, City of

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.

 

21

Samples

0

Samples exceeding legal limit (MCL)

7

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20181.20 ppb111.20 ppb
20190.218 ppb41ND - 0.870 ppb
20201.48 ppb440.500 ppb - 2.40 ppb
2021ND40ND
20220.190 ppb41ND - 0.760 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
2018-09-2410491381.20 ppb
2019-03-251139615ND
2019-06-241191374ND
2019-09-2312469050.870 ppb
2019-12-161291367ND
2020-03-1713425190.500 ppb
2020-06-1614065142.40 ppb
2020-09-2215196281.80 ppb
2020-12-1417119251.20 ppb
2021-04-051812078ND
2021-06-211865529ND
2021-11-302043414ND
2021-12-142069514ND
2022-03-282224200ND
2022-06-282289438ND
2022-09-202362976ND
2022-12-1224151810.760 ppb
2023-03-202469537ND
2023-06-192520981ND
2023-09-242582380ND
2023-12-182627995ND