Know Your Environment. Protect Your Health.

Chloroform

City of Rio Hondo

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.

 

58

Samples

0

Samples exceeding legal limit (MCL)

26

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
201829.5 ppb98ND - 74.4 ppb
20190.378 ppb92ND - 1.90 ppb
20200.175 ppb122ND - 1.10 ppb
20210.220 ppb102ND - 1.10 ppb
20220.944 ppb95ND - 2.20 ppb
20232.03 ppb97ND - 5.50 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
2018-02-20AE1440174.4 ppb
2018-02-20AE1438458.1 ppb
2018-04-25AE2390059.0 ppb
2018-04-25AE2389863.4 ppb
2018-08-15AE371801.50 ppb
2018-08-15AE371813.10 ppb
2018-08-15AE37208ND
2018-10-11AE432471.60 ppb
2018-10-11AE432484.20 ppb
2019-02-08AE53730ND
2019-02-08AE53743ND
2019-04-04AE61179ND
2019-04-04AE61181ND
2019-07-10AE739361.50 ppb
2019-07-10AE73887ND
2019-07-10AE73882ND
2019-10-23AE87400ND
2019-10-23AE874051.90 ppb
2020-03-06AF01686ND
2020-03-06AF01701ND
2020-03-06AF01729ND
2020-06-09AF14636ND
2020-06-09AF14640ND
2020-06-09AF14663ND
2020-08-19AF242631.10 ppb
2020-08-19AF242641.000 ppb
2020-08-19AF24306ND
2020-10-07AF29837ND
2020-10-07AF29811ND
2020-10-07AF29818ND
2021-01-27AF41320ND
2021-01-27AF41321ND
2021-01-27AF41377ND
2021-04-29AF51908ND
2021-04-29AF51915ND
2021-04-29AF51966ND
2021-08-18AF668301.10 ppb
2021-08-18AF668311.10 ppb
2021-12-20AF79063ND
2021-12-20AF79071ND
2022-02-03AF83271ND
2022-02-03AF83280ND
2022-02-03AF83317ND
2022-04-19AF937131.10 ppb
2022-04-19AF93719ND
2022-09-26AG147092.20 ppb
2022-09-26AG147102.10 ppb
2022-11-17AG191881.60 ppb
2022-11-17AG191991.50 ppb
2023-02-01AG271161.000 ppb
2023-02-01AG27117ND
2023-02-01AG27165ND
2023-05-18AG410272.30 ppb
2023-05-18AG410282.00 ppb
2023-08-03AG512705.50 ppb
2023-08-03AG512955.40 ppb
2023-11-09AG630151.000 ppb
2023-11-09AG630161.10 ppb