Know Your Environment. Protect Your Health.

Chloroform

Paw Penn District

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.

 

35

Samples

0

Samples exceeding legal limit (MCL)

22

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
201813.2 ppb64ND - 69.5 ppb
20191.29 ppb1610ND - 6.70 ppb
20203.07 ppb64ND - 12.9 ppb
20211.05 ppb21ND - 2.10 ppb
20221.23 ppb32ND - 3.00 ppb
20231.40 ppb21ND - 2.80 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
2018-07-054020740169.5 ppb
2018-07-05402075013.10 ppb
2018-10-088102701-03ND
2018-10-088102701-022.40 ppb
2018-10-088102701-04ND
2018-10-088102701-014.30 ppb
2019-01-07424997011.20 ppb
2019-01-07424998011.000 ppb
2019-01-07424983010.700 ppb
2019-01-0742498401ND
2019-04-08436589010.900 ppb
2019-04-0843658701ND
2019-04-0843658601ND
2019-04-0843658801ND
2019-07-08450166012.40 ppb
2019-07-0845016501ND
2019-07-08450184016.70 ppb
2019-07-08450183010.600 ppb
2019-10-07468322011.80 ppb
2019-10-07468320012.60 ppb
2019-10-0746832101ND
2019-10-07468319012.70 ppb
2020-01-06ND
2020-01-061.80 ppb
2020-01-06ND
2020-01-060.700 ppb
2020-07-063.00 ppb
2020-10-0712.9 ppb
2021-07-062.10 ppb
2021-10-06ND
2022-05-050.700 ppb
2022-07-053.00 ppb
2022-10-06ND
2023-07-052.80 ppb
2023-10-06ND