Know Your Environment. Protect Your Health.

Chloroform

Montrose Boydell 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.

 

48

Samples

0

Samples exceeding legal limit (MCL)

14

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20188.26 ppb91ND - 74.3 ppb
20190.183 ppb61ND - 1.10 ppb
20200.288 ppb82ND - 1.20 ppb
20212.96 ppb93ND - 24.0 ppb
202221.8 ppb86ND - 115.0 ppb
20231.06 ppb81ND - 8.46 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
2018-01-0918010000201ND
2018-01-0918010000101ND
2018-04-1018102002802ND
2018-04-1018102002902ND
2018-07-0918193007402ND
2018-07-0918193007302ND
2018-10-0918284000801ND
2018-10-0918284000902ND
2018-10-091828400070274.3 ppb
2019-02-2619059002202ND
2019-02-2619059002302ND
2019-08-0619220014502ND
2019-08-0619220014602ND
2019-10-0719283004502ND
2019-10-07192830046021.10 ppb
2020-01-2920030004702ND
2020-01-2920030004802ND
2020-04-2020114007902ND
2020-04-2020114007802ND
2020-07-2120204002502ND
2020-07-2120204002602ND
2020-10-20202960132021.20 ppb
2020-10-20202960133021.10 ppb
2021-01-1221014004102ND
2021-01-1221014004202ND
2021-04-2021112006302ND
2021-04-2021112006402ND
2021-07-2021203006202ND
2021-07-2021203006302ND
2021-10-12212870061021.20 ppb
2021-10-122128700600224.0 ppb
2021-10-12212870059011.42 ppb
2022-01-1122013011702115.0 ppb
2022-01-1122013011602ND
2022-04-19O197139-THM-11.68 ppb
2022-04-19O197138-THM-11.11 ppb
2022-07-20O199886-THM-18.31 ppb
2022-07-20O199887-THM-117.9 ppb
2022-10-18O202984-THM-1ND
2022-10-18O202985-THM-130.5 ppb
2023-01-10O205107-THM-1ND
2023-01-10O205108-THM-18.46 ppb
2023-04-24O208301-THM-1ND
2023-04-24O208300-THM-1ND
2023-07-19O210740-THM-1ND
2023-07-19O210741-THM-1ND
2023-10-18O213097-THM-1ND
2023-10-18O213098-THM-1ND