Know Your Environment. Protect Your Health.

Chloroform

Stanhope W Department

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.

 

25

Samples

0

Samples exceeding legal limit (MCL)

9

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.500 ppb72ND - 2.10 ppb
20191.53 ppb32ND - 3.80 ppb
20200.500 ppb31ND - 1.50 ppb
20210.510 ppb21ND - 1.02 ppb
20220.372 ppb52ND - 1.34 ppb
20230.356 ppb51ND - 1.78 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
2018-03-12380312079ND
2018-07-10380710183ND
2018-08-273808270921.40 ppb
2018-08-27380827091ND
2018-09-253809251672.10 ppb
2018-09-25380925169ND
2018-09-25380925168ND
2019-07-10390710242ND
2019-08-153908152173.80 ppb
2019-08-153908152160.800 ppb
2020-07-163116417001ND
2020-08-13200813030-03ND
2020-08-13200813030-041.50 ppb
2021-08-19210819081-021.02 ppb
2021-08-19210819081-01ND
2022-03-10220310064-05ND
2022-03-10220310064-04ND
2022-03-10220310064-03ND
2022-08-22220822073-061.34 ppb
2022-08-22220822073-050.520 ppb
2023-08-23230823084-041.78 ppb
2023-08-23230823084-03ND
2023-12-13231213082-04ND
2023-12-13231213082-06ND
2023-12-13231213082-05ND