Know Your Environment. Protect Your Health.

Chloroform

Clark Public Utilities

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.

 

62

Samples

0

Samples exceeding legal limit (MCL)

24

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2018ND130ND
20190.373 ppb104ND - 1.50 ppb
2020N/A00N/A
20210.473 ppb115ND - 1.30 ppb
20220.727 ppb158ND - 1.60 ppb
20231.03 ppb137ND - 2.70 ppb

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
2018-08-01ND
2018-08-01ND
2018-08-01ND
2018-08-01ND
2018-08-01ND
2018-08-20ND
2018-08-20ND
2018-08-28ND
2018-08-28ND
2018-09-18ND
2018-09-18ND
2018-09-18ND
2018-11-18ND
2019-02-24ND
2019-02-24ND
2019-06-101.50 ppb
2019-06-100.570 ppb
2019-07-22ND
2019-08-08ND
2019-08-08ND
2019-09-05ND
2019-10-100.660 ppb
2019-10-101.000 ppb
2021-01-264069468ND
2021-01-264069467ND
2021-04-1241012271.10 ppb
2021-04-1241012281.30 ppb
2021-06-304143007ND
2021-07-2041491270.570 ppb
2021-07-204149126ND
2021-08-024169145ND
2021-08-024169136ND
2021-10-1441949141.30 ppb
2021-10-1441949130.930 ppb
2022-01-2042418151.20 ppb
2022-01-2042418131.60 ppb
2022-04-1842729121.50 ppb
2022-04-1842729131.30 ppb
2022-07-0743094071.40 ppb
2022-07-0743094081.20 ppb
2022-07-274328694ND
2022-07-284328685ND
2022-07-284328695ND
2022-07-284328702ND
2022-08-034328680ND
2022-08-034328676ND
2022-08-034328682ND
2022-10-0343616081.30 ppb
2022-10-0343616091.40 ppb
2023-01-2444114071.10 ppb
2023-01-2444114082.70 ppb
2023-04-0544913582.20 ppb
2023-04-0544367012.10 ppb
2023-05-234545879ND
2023-06-124473924ND
2023-06-124473922ND
2023-06-124473920ND
2023-06-124473923ND
2023-07-114485447ND
2023-07-1144854460.970 ppb
2023-10-0245315452.00 ppb
2023-10-0245315462.30 ppb