Know Your Environment. Protect Your Health.

Chloroform

Patton Village West Water System

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.

 

29

Samples

0

Samples exceeding legal limit (MCL)

2

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2018ND10ND
2019ND10ND
2020ND80ND
2021ND40ND
20221.09 ppb71ND - 7.60 ppb
20230.188 ppb81ND - 1.50 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
2018-09-19AE40721ND
2019-12-02AE90828ND
2020-07-30AF21369ND
2020-07-30AF21391ND
2020-07-30AF21395ND
2020-07-30AF21433ND
2020-07-30AF21435ND
2020-10-05AF29481ND
2020-10-05AF29483ND
2020-10-05AF29485ND
2021-01-12AF38828ND
2021-01-12AF38834ND
2021-05-07AF52928ND
2021-05-07AF52999ND
2022-06-06AF99588ND
2022-06-06AF99679ND
2022-06-06AF99677ND
2022-08-10AG086127.60 ppb
2022-08-10AG08614ND
2022-10-18AG17490ND
2022-12-05AG20720ND
2023-01-10AG23727ND
2023-01-10AG23741ND
2023-01-10AG23747ND
2023-04-03AG35153ND
2023-05-10AG399481.50 ppb
2023-05-10AG40025ND
2023-07-14AG48828ND
2023-10-26AG61269ND