Know Your Environment. Protect Your Health.

Chloroform

City of Shavano Park

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.

 

30

Samples

0

Samples exceeding legal limit (MCL)

4

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.240 ppb51ND - 1.20 ppb
20190.800 ppb52ND - 2.40 ppb
2020ND50ND
20210.240 ppb51ND - 1.20 ppb
2022ND50ND
2023ND50ND

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
2018-03-02AE16674ND
2018-03-02AE16676ND
2018-03-02AE16700ND
2018-03-02AE16668ND
2018-05-14AE261581.20 ppb
2019-04-03AE61047ND
2019-04-03AE61039ND
2019-04-03AE61035ND
2019-04-03AE610292.40 ppb
2019-06-14AE708551.60 ppb
2020-02-24AE99519ND
2020-02-24AE99539ND
2020-02-24AE99541ND
2020-05-15AF11864ND
2020-05-15AF11875ND
2021-02-23AF43941ND
2021-02-23AF43945ND
2021-02-23AF43943ND
2021-06-18AF588461.20 ppb
2021-06-18AF58893ND
2022-03-09AF88394ND
2022-03-09AF88406ND
2022-03-09AF88408ND
2022-03-09AF88412ND
2022-06-21AG01686ND
2023-06-22AG45577ND
2023-06-22AG45585ND
2023-06-22AG45593ND
2023-06-22AG45601ND
2023-06-22AG45603ND