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EWG's Tap Water Database — 2021 UPDATE

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Chloroform

University of Connecticut - Main Campus

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

 

130

Samples

0

Samples exceeding legal limit (MCL)

118

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20142.22 ppb1918ND - 7.00 ppb
20152.51 ppb1916ND - 6.80 ppb
20163.64 ppb1816ND - 9.40 ppb
20175.65 ppb2220ND - 16.0 ppb
20188.89 ppb2624ND - 24.6 ppb
20196.94 ppb2624ND - 20.3 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
2014-03-10BG17096TTHM1.10 ppb
2014-03-10BG17099TTHM2.70 ppb
2014-03-10BG17101TTHM0.990 ppb
2014-03-10BG17102TTHM1.40 ppb
2014-04-24BG36616VOC10.570 ppb
2014-04-24BG36617VOC1ND
2014-06-12BG56337TTHM1.80 ppb
2014-06-12BG56340TTHM7.00 ppb
2014-06-12BG56345TTHM2.50 ppb
2014-06-12BG56346TTHM2.20 ppb
2014-06-27BG66061VOC11.90 ppb
2014-09-16BH14164TTHM1.50 ppb
2014-09-16BH14167TTHM6.30 ppb
2014-09-16BH14172TTHM1.20 ppb
2014-09-16BH14173TTHM1.40 ppb
2014-12-10BH51407TTHM2.20 ppb
2014-12-10BH51410TTHM3.80 ppb
2014-12-10BH51415TTHM1.90 ppb
2014-12-10BH51416TTHM1.80 ppb
2015-01-22BH66098VOC1ND
2015-01-22BH66096VOC1ND
2015-01-22BH66097VOC1ND
2015-03-09BH80470TTHM1.30 ppb
2015-03-09BH80473TTHM3.30 ppb
2015-03-12BH82672TTHM1.50 ppb
2015-03-12BH82671TTHM1.30 ppb
2015-06-08BJ27390TTHM2.00 ppb
2015-06-08BJ27398TTHM1.90 ppb
2015-06-08BJ27393TTHM6.30 ppb
2015-06-08BJ27397TTHM5.40 ppb
2015-09-22BJ95542TTHM2.10 ppb
2015-09-22BJ95541TTHM2.80 ppb
2015-09-22BJ95539TTHM2.80 ppb
2015-09-22BJ95540TTHM6.80 ppb
2015-12-09BK34675TTHM1.90 ppb
2015-12-09BK34680TTHM2.20 ppb
2015-12-09BK34679TTHM1.90 ppb
2015-12-09BK34678TTHM4.20 ppb
2016-03-09BK75989TTHM2.20 ppb
2016-03-09BK75990TTHM2.20 ppb
2016-03-09BK75991TTHM1.90 ppb
2016-03-09BK75992TTHM4.10 ppb
2016-06-09BN51405TTHM2.10 ppb
2016-06-09BN51408TTHM7.10 ppb
2016-06-09BN51412TTHM4.80 ppb
2016-06-09BN51413TTHM2.20 ppb
2016-06-14BN54228VOC1ND
2016-06-14BN54227VOC1ND
2016-09-21BV20288TTHM2.70 ppb
2016-09-21BV20289TTHM3.00 ppb
2016-09-21BV20290TTHM2.10 ppb
2016-09-21BV20291TTHM7.80 ppb
2016-12-13BX04254TTHM4.70 ppb
2016-12-13BX04255TTHM4.90 ppb
2016-12-13BX04256TTHM9.40 ppb
2016-12-13BX04257TTHM4.30 ppb
2017-03-08BX81804TTHM3.90 ppb
2017-03-08BX81805TTHM3.50 ppb
2017-03-08BX81806TTHM13.0 ppb
2017-03-08BX81807TTHM4.40 ppb
2017-06-13BY38124TTHM2.40 ppb
2017-06-13BY38125TTHM7.40 ppb
2017-06-13BY38126TTHM3.20 ppb
2017-06-13BY38127TTHM5.20 ppb
2017-08-09BY81246TTHM9.10 ppb
2017-08-09BY81247TTHM9.00 ppb
2017-08-09BY81248TTHM4.30 ppb
2017-08-10BY82233TTHM8.20 ppb
2017-09-05BY94975TTHM8.80 ppb
2017-09-05BY94976TTHM16.0 ppb
2017-09-06BY95732TTHM6.30 ppb
2017-09-07BY96696TTHM2.90 ppb
2017-12-11BZ54499VOC1ND
2017-12-11BZ54498VOC1ND
2017-12-12BZ58240TTHM6.50 ppb
2017-12-12BZ58241TTHM2.20 ppb
2017-12-12BZ58242TTHM4.60 ppb
2017-12-12BZ58243TTHM3.40 ppb
2018-03-15CA02987TTHM11.0 ppb
2018-03-15CA02988TTHM4.50 ppb
2018-03-15CA02989TTHM16.0 ppb
2018-03-15CA02990TTHM3.00 ppb
2018-06-12CA68568TTHM13.0 ppb
2018-06-12CA68569TTHM11.0 ppb
2018-06-12CA68570TTHM14.0 ppb
2018-06-12CA68571TTHM3.00 ppb
2018-09-19DBP 20050618214.0 ppb
2018-09-19DBP 20050618423.8 ppb
2018-09-19DBP 2005061864.40 ppb
2018-09-19DBP 2005061896.00 ppb
2018-09-25DBP 20050672013.0 ppb
2018-09-25DBP 20050672124.6 ppb
2018-09-25DBP 2005067224.90 ppb
2018-09-25DBP 20050672310.4 ppb
2018-09-26DBP 2005069663.80 ppb
2018-09-27DBP 20050707310.00 ppb
2018-12-04DBP 2005147242.20 ppb
2018-12-04DBP 20051472517.8 ppb
2018-12-04DBP 2005147263.40 ppb
2018-12-04DBP 2005147286.60 ppb
2018-12-12VOC1 200515892ND
2018-12-12VOC1 200515895ND
2018-12-17DBP 2005162818.20 ppb
2018-12-17DBP 2005162822.50 ppb
2019-03-18DBP 2005250245.20 ppb
2019-03-18DBP 2005250265.30 ppb
2019-03-18DBP 2005250294.60 ppb
2019-03-18DBP 20052503110.00 ppb
2019-03-18DBP 2005250336.10 ppb
2019-03-18DBP 2005250342.60 ppb
2019-06-24DBP 2005375417.70 ppb
2019-06-24DBP 2005375428.40 ppb
2019-06-24DBP 2005375434.10 ppb
2019-06-25DBP 2005378066.80 ppb
2019-06-25DBP 20053780711.7 ppb
2019-06-25DBP 20053780819.2 ppb
2019-09-16DBP 2005490017.60 ppb
2019-09-16DBP 2005490023.00 ppb
2019-09-16DBP 2005490406.10 ppb
2019-09-16DBP 20054904119.1 ppb
2019-09-16DBP 2005490436.20 ppb
2019-09-16DBP 2005490443.30 ppb
2019-11-21VOC1 200557816ND
2019-11-21VOC1 200557817ND
2019-12-09DBP 2005594125.20 ppb
2019-12-09DBP 2005594164.00 ppb
2019-12-09DBP 2005594193.70 ppb
2019-12-09DBP 20055942220.3 ppb
2019-12-09DBP 2005594258.20 ppb
2019-12-09DBP 2005594272.10 ppb