Menu

EWG's Tap Water Database — 2021 UPDATE

Donate

Chloroform

Town of Boone

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.

MORE ABOUT THIS CONTAMINANT

 

92

Samples

0

Samples exceeding legal limit (MCL)

92

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
201423.9 ppb14149.90 ppb - 60.0 ppb
201524.2 ppb141412.0 ppb - 68.0 ppb
201629.4 ppb16165.40 ppb - 67.0 ppb
201730.6 ppb16169.00 ppb - 95.0 ppb
201833.8 ppb16167.80 ppb - 94.0 ppb
201931.7 ppb16166.00 ppb - 64.0 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 0.4 ppb

The EWG Health Guideline of 0.4 ppb for chloroform was proposed in 2018 by the California Office of Environmental Health Hazard Assessment as a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.

ppb = parts per billion

All test results

Date Lab ID Result
2014-02-04921887370029.90 ppb
2014-02-049218873700332.0 ppb
2014-02-049218873700419.0 ppb
2014-02-049218873700512.0 ppb
2014-02-049218873700112.0 ppb
2014-05-0692200307001DIS28.0 ppb
2014-05-0692200307002DIS18.0 ppb
2014-05-0692200307003DIS20.0 ppb
2014-08-0592212154001TTH60.0 ppb
2014-08-0592212154002TTH34.0 ppb
2014-08-0592212154003TTH30.0 ppb
2014-11-1292225463003TTH15.0 ppb
2014-11-1292225463002TTH16.0 ppb
2014-11-1292225463001TTH28.0 ppb
2015-02-1014.0 ppb
2015-02-1013.0 ppb
2015-02-1012.0 ppb
2015-05-1212.0 ppb
2015-05-1214.0 ppb
2015-05-1222.0 ppb
2015-08-1132.0 ppb
2015-08-1168.0 ppb
2015-08-1130.0 ppb
2015-08-3115.0 ppb
2015-11-0933.0 ppb
2015-11-0912.0 ppb
2015-11-0916.0 ppb
2015-11-0946.0 ppb
2016-02-0892285721001TTH9.90 ppb
2016-02-0892285721002TTH6.60 ppb
2016-02-0892285721003TTH27.0 ppb
2016-02-0892285721004TTH5.40 ppb
2016-05-0392296315001TTH27.0 ppb
2016-05-0392296315002TTH22.0 ppb
2016-05-0392296315003TTH47.0 ppb
2016-05-0392296315004TTH19.0 ppb
2016-08-0292307720004TTH24.0 ppb
2016-08-0292307720003TTH67.0 ppb
2016-08-0292307720002TTH28.0 ppb
2016-08-0292307720001TTH56.0 ppb
2016-11-0392318558002TTH23.0 ppb
2016-11-0392318558004TTH20.0 ppb
2016-11-0392318558003TTH52.0 ppb
2016-11-0392318558001TTH37.0 ppb
2017-02-0892329381004TTH9.00 ppb
2017-02-0892329381003TTH25.0 ppb
2017-02-0892329381002TTH9.40 ppb
2017-02-0892329381001TTH18.0 ppb
2017-05-0392339477003TTH56.0 ppb
2017-05-0392339477002TTH20.0 ppb
2017-05-0392339477001TTH33.0 ppb
2017-05-0392339477004TTH17.0 ppb
2017-08-0892350885001TTH56.0 ppb
2017-08-0892350885002TTH34.0 ppb
2017-08-0892350885003TTH95.0 ppb
2017-08-0892350885004TTH24.0 ppb
2017-11-1492363472001TTH27.0 ppb
2017-11-1492363472003TTH47.0 ppb
2017-11-1492363472002TTH10.00 ppb
2017-11-1492363472004TTH9.60 ppb
2018-02-0792372639004TTH 7.80 ppb
2018-02-0792372639003TTH 32.0 ppb
2018-02-0792372639002TTH 8.70 ppb
2018-02-0792372639001TTH 11.0 ppb
2018-05-0892384010004TTH 17.0 ppb
2018-05-0892384010001TTH 30.0 ppb
2018-05-0892384010002TTH 18.0 ppb
2018-05-0892384010003TTH 58.0 ppb
2018-08-1492395788004TTH 33.0 ppb
2018-08-1492395788003TTH 94.0 ppb
2018-08-1492395788002TTH 36.0 ppb
2018-08-1492395788001TTH 69.0 ppb
2018-11-0792406516001TTH 40.0 ppb
2018-11-0792406516002TTH 21.0 ppb
2018-11-0792406516003TTH 44.0 ppb
2018-11-0792406516004TTH 21.0 ppb
2019-02-1292417651001_377012.0 ppb
2019-02-1292417651002_37707.00 ppb
2019-02-1292417651003_377014.0 ppb
2019-02-1292417651004_37706.00 ppb
2019-05-0792428585001_377031.0 ppb
2019-05-0792428585004_377016.0 ppb
2019-05-0792428585003_377043.0 ppb
2019-05-0792428585002_377023.0 ppb
2019-08-0792440540002_377038.0 ppb
2019-08-0792440540004_377033.0 ppb
2019-08-0792440540003_377055.0 ppb
2019-08-0792440540001_377064.0 ppb
2019-11-0592452480004_377022.0 ppb
2019-11-0592452480003_377061.0 ppb
2019-11-0592452480002_377035.0 ppb
2019-11-0592452480001_377047.0 ppb