Know Your Environment. Protect Your Health.

Chloroform

City of Miles

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.

 

54

Samples

0

Samples exceeding legal limit (MCL)

35

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.801 ppb95ND - 1.85 ppb
20192.52 ppb991.60 ppb - 5.21 ppb
20202.35 ppb991.19 ppb - 4.23 ppb
20211.68 ppb97ND - 5.10 ppb
20220.610 ppb94ND - 1.57 ppb
20230.129 ppb91ND - 1.16 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
2018-02-22Q18075340091.04 ppb
2018-02-22Q1807534010ND
2018-02-22Q1807534007ND
2018-04-25Q1816852001ND
2018-04-25Q1816852003ND
2018-07-18Q18285390021.39 ppb
2018-07-18Q18285390031.16 ppb
2018-12-05Q18497590021.77 ppb
2018-12-05Q18497590031.85 ppb
2019-03-07Q19098310012.01 ppb
2019-03-07Q19098310031.93 ppb
2019-03-07Q19098310051.74 ppb
2019-05-15Q19255800021.83 ppb
2019-05-15Q19255800031.76 ppb
2019-08-01Q19503970025.21 ppb
2019-08-01Q19503970034.78 ppb
2019-11-05Q19751030021.79 ppb
2019-11-05Q19751030031.60 ppb
2020-02-19Q20064240011.42 ppb
2020-02-19Q20064240021.47 ppb
2020-02-19Q20064240061.19 ppb
2020-05-21Q20204170023.19 ppb
2020-05-21Q20204170033.20 ppb
2020-07-30Q20299100024.23 ppb
2020-07-30Q20299100033.53 ppb
2020-11-18Q20458100011.45 ppb
2020-11-18Q20458100021.50 ppb
2021-03-09Q21060940041.15 ppb
2021-03-09Q21060940111.15 ppb
2021-03-09Q21060940101.08 ppb
2021-05-18Q2112972003ND
2021-05-18Q21129720041.06 ppb
2021-07-21Q21191280015.10 ppb
2021-07-21Q21191280024.60 ppb
2021-11-18Q2132327002ND
2021-11-18Q21323270031.01 ppb
2022-02-15Q2205466001ND
2022-02-15Q2205466003ND
2022-02-15Q2205466005ND
2022-05-31Q22153650021.57 ppb
2022-05-31Q22153650031.09 ppb
2022-07-21Q22209100021.48 ppb
2022-07-21Q22209100031.35 ppb
2022-10-26Q2232283001ND
2022-10-26Q2232283002ND
2023-02-16Q2306683001ND
2023-02-16Q2306683005ND
2023-02-16Q2306683006ND
2023-04-20Q2314829002ND
2023-04-20Q2314829003ND
2023-08-02Q23314630021.16 ppb
2023-08-02Q2331463003ND
2023-11-09Q2348205002ND
2023-11-09Q2348205003ND