Know Your Environment. Protect Your Health.

Chloroform

Shadow Bay Subdivision

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.

 

13

Samples

0

Samples exceeding legal limit (MCL)

8

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.550 ppb21ND - 1.10 ppb
20191.15 ppb221.10 ppb - 1.20 ppb
20202.90 ppb221.40 ppb - 4.40 ppb
20211.20 ppb221.10 ppb - 1.30 ppb
2022ND20ND
20230.600 ppb31ND - 1.80 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
2018-05-23AE274321.10 ppb
2018-05-23AE27502ND
2019-07-18AE750151.20 ppb
2019-07-18AE750391.10 ppb
2020-08-18AF240771.40 ppb
2020-08-18AF241094.40 ppb
2021-09-13AF694921.10 ppb
2021-09-13AF695321.30 ppb
2022-09-12AG12429ND
2022-09-12AG12461ND
2023-06-14AG44489ND
2023-06-14AG44541ND
2023-12-14AG666891.80 ppb