Know Your Environment. Protect Your Health.

Chloroform

City of Spokane

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.

 

60

Samples

0

Samples exceeding legal limit (MCL)

15

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.244 ppb115ND - 0.760 ppb
20190.106 ppb183ND - 0.750 ppb
2020N/A00N/A
20210.193 ppb115ND - 0.590 ppb
20220.292 ppb108ND - 0.530 ppb
20230.199 ppb105ND - 0.600 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
2018-01-30ND
2018-01-300.380 ppb
2018-01-30ND
2018-01-300.470 ppb
2018-05-10ND
2018-05-100.500 ppb
2018-07-17ND
2018-07-17ND
2018-07-17ND
2018-11-080.760 ppb
2018-11-080.570 ppb
2019-02-14ND
2019-02-14ND
2019-05-09ND
2019-05-09ND
2019-07-23ND
2019-07-23ND
2019-07-26ND
2019-07-26ND
2019-07-260.580 ppb
2019-07-26ND
2019-07-26ND
2019-07-26ND
2019-07-26ND
2019-07-26ND
2019-08-08ND
2019-08-08ND
2019-11-130.750 ppb
2019-11-130.570 ppb
2021-01-264066970ND
2021-01-264066969ND
2021-02-094097358ND
2021-02-0940973560.590 ppb
2021-05-1341152890.370 ppb
2021-05-134115288ND
2021-07-274195356ND
2021-08-1141598150.200 ppb
2021-08-114159816ND
2021-11-1042038310.530 ppb
2021-11-1042038300.430 ppb
2022-02-1042440950.300 ppb
2022-02-1042440940.370 ppb
2022-05-1242823050.430 ppb
2022-05-1242823060.260 ppb
2022-07-264319391ND
2022-07-264319393ND
2022-08-1143270170.260 ppb
2022-08-1143270160.270 ppb
2022-11-1043730020.530 ppb
2022-11-1043730010.500 ppb
2023-01-244399432ND
2023-02-0944247010.290 ppb
2023-02-0944247000.340 ppb
2023-05-104452949ND
2023-05-104452948ND
2023-07-254507772ND
2023-08-0344988190.230 ppb
2023-08-034498818ND
2023-11-0945476100.600 ppb
2023-11-0945476110.530 ppb