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EWG's Tap Water Database — 2019 UPDATE

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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.

 

52

Samples

0

Samples exceeding legal limit (MCL)

19

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20120.220 ppb51ND - 1.10 ppb
2013ND80ND
20141.000 ppb86ND - 1.90 ppb
20151.12 ppb116ND - 2.80 ppb
20160.564 ppb113ND - 2.50 ppb
20170.516 ppb93ND - 1.90 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
2012-03-06AB833201.10 ppb
2012-03-06AB83322ND
2012-05-24AB90793ND
2012-05-24AB90786ND
2012-12-121212534002ND
2013-01-281301736003ND
2013-01-281301736002ND
2013-04-241304878002ND
2013-04-241304878003ND
2013-09-09Q1306764005ND
2013-09-09Q1306764004ND
2013-10-31Q1311057005ND
2013-10-31Q1311057004ND
2014-02-27AC45056ND
2014-02-27AC45050ND
2014-05-28AC553691.000 ppb
2014-05-28AC553701.10 ppb
2014-09-23AC681461.60 ppb
2014-09-23AC681481.90 ppb
2014-12-09AC740361.10 ppb
2014-12-09AC740501.30 ppb
2015-03-10AC83701ND
2015-03-10AC83697ND
2015-05-26AC935012.60 ppb
2015-05-26AC935022.20 ppb
2015-05-26AC934312.80 ppb
2015-07-20AD001461.70 ppb
2015-07-20AD001161.80 ppb
2015-09-29AD088771.20 ppb
2015-11-03AD12370ND
2015-11-03AD12325ND
2015-11-03AD12415ND
2016-03-24AD30389ND
2016-03-24AD30390ND
2016-03-24AD30474ND
2016-05-18AD37248ND
2016-05-18AD37245ND
2016-05-18AD37306ND
2016-08-02AD469052.50 ppb
2016-08-02AD468561.80 ppb
2016-08-02AD468531.90 ppb
2016-11-30AD59821ND
2016-11-30AD59816ND
2017-03-01Q1708976006ND
2017-03-01Q1708976005ND
2017-03-01Q1708976001ND
2017-05-17Q1720175003ND
2017-05-17Q17201750011.08 ppb
2017-07-27Q17312060031.66 ppb
2017-07-27Q17312060021.90 ppb
2017-11-02Q1756369003ND
2017-11-02Q1756369001ND