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EWG's Tap Water Database — 2021 UPDATE

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Chloroform

Connecticut Water Company - Northern Region-Western System

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

 

230

Samples

0

Samples exceeding legal limit (MCL)

203

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2013N/A00N/A
201418.1 ppb4434ND - 58.9 ppb
201516.5 ppb3934ND - 45.0 ppb
201617.9 ppb3733ND - 46.0 ppb
201722.1 ppb3833ND - 62.0 ppb
201834.9 ppb3836ND - 82.0 ppb
201925.5 ppb3433ND - 51.0 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
2014-01-24BG03077VOC1ND
2014-01-29BG04659VOC10.500 ppb
2014-02-041747THM27.2 ppb
2014-02-041748THM10.5 ppb
2014-02-041749THM26.8 ppb
2014-02-041750THM7.80 ppb
2014-02-041751THM15.7 ppb
2014-02-041752THM14.3 ppb
2014-02-041753THM26.7 ppb
2014-02-041754THM37.6 ppb
2014-02-07BG08003VOC1ND
2014-04-03BG27981VOC1ND
2014-04-094561VOC118.0 ppb
2014-05-066108THM35.5 ppb
2014-05-066109THM58.9 ppb
2014-05-066110THM20.7 ppb
2014-05-066111THM56.2 ppb
2014-05-066112THM11.9 ppb
2014-05-066113THM45.0 ppb
2014-05-066114THM11.1 ppb
2014-05-096107THM26.0 ppb
2014-05-21BG47680VOC1ND
2014-06-04BG53346VOC1ND
2014-06-06BG54002VOC1ND
2014-06-17BG60666VOC1ND
2014-06-19BG62968VOC1ND
2014-07-11BG73249VOC1ND
2014-08-05BG88648TTHM17.0 ppb
2014-08-05BG88649TTHM32.0 ppb
2014-08-05BG88650TTHM37.0 ppb
2014-08-05BG88651TTHM19.0 ppb
2014-08-05BG88652TTHM44.0 ppb
2014-08-05BG88653TTHM7.30 ppb
2014-08-05BG88654TTHM23.0 ppb
2014-08-05BG88655TTHM14.0 ppb
2014-11-21BH44966VOC1ND
2014-11-25BH46470TTHM9.80 ppb
2014-11-25BH46471TTHM29.0 ppb
2014-11-25BH46472TTHM27.0 ppb
2014-11-25BH46473TTHM24.0 ppb
2014-11-25BH46474TTHM30.0 ppb
2014-11-25BH46475TTHM9.10 ppb
2014-11-25BH46476TTHM12.0 ppb
2014-11-25BH46477TTHM12.0 ppb
2015-01-20BH64902VOC16.70 ppb
2015-02-25BH77219TTHM8.20 ppb
2015-02-25BH77225TTHM18.0 ppb
2015-02-25BH77221TTHM28.0 ppb
2015-02-25BH77220TTHM36.0 ppb
2015-02-25BH77224TTHM7.90 ppb
2015-02-25BH77222TTHM18.0 ppb
2015-02-25BH77223TTHM38.0 ppb
2015-02-25BH77226TTHM15.0 ppb
2015-03-06BH80296VOC1ND
2015-04-29BJ09906VOC1ND
2015-04-30BJ10443VOC1ND
2015-05-21BJ20481TTHM6.90 ppb
2015-05-21BJ20487TTHM5.50 ppb
2015-05-21BJ20488TTHM6.90 ppb
2015-05-21BJ20482TTHM9.40 ppb
2015-05-21BJ20483TTHM8.40 ppb
2015-05-21BJ20486TTHM6.30 ppb
2015-05-21BJ20485TTHM20.0 ppb
2015-05-21BJ20484TTHM19.0 ppb
2015-07-01BJ40227VOC1ND
2015-07-02BJ41078VOC1ND
2015-07-30BJ65812VOC10.870 ppb
2015-08-20BJ78788TTHM17.0 ppb
2015-08-20BJ78787TTHM16.0 ppb
2015-08-20BJ78783TTHM29.0 ppb
2015-08-20BJ78782TTHM45.0 ppb
2015-08-20BJ78786TTHM8.30 ppb
2015-08-20BJ78784TTHM35.0 ppb
2015-08-20BJ78781TTHM13.0 ppb
2015-08-20BJ78785TTHM45.0 ppb
2015-11-24BK27966TTHM12.0 ppb
2015-11-24BK27973TTHM12.0 ppb
2015-11-24BK27971TTHM6.90 ppb
2015-11-24BK27968TTHM37.0 ppb
2015-11-24BK27970TTHM40.0 ppb
2015-11-24BK27969TTHM22.0 ppb
2015-11-24BK27967TTHM38.0 ppb
2015-11-24BK27972TTHM10.00 ppb
2016-01-12BK51386VOC14.40 ppb
2016-01-15BK53768VOC1ND
2016-02-04BK61857TTHM8.40 ppb
2016-02-04BK61858TTHM29.0 ppb
2016-02-04BK61859TTHM25.0 ppb
2016-02-04BK61860TTHM23.0 ppb
2016-02-04BK61861TTHM31.0 ppb
2016-02-04BK61862TTHM7.30 ppb
2016-02-04BK61863TTHM11.0 ppb
2016-02-04BK61864TTHM12.0 ppb
2016-05-05BN26300TTHM9.70 ppb
2016-05-05BN26301TTHM41.0 ppb
2016-05-05BN26302TTHM31.0 ppb
2016-05-05BN26303TTHM29.0 ppb
2016-05-05BN26304TTHM42.0 ppb
2016-05-05BN26305TTHM5.90 ppb
2016-05-05BN26306TTHM11.0 ppb
2016-05-05BN26307TTHM13.0 ppb
2016-05-25BN40000VOC1ND
2016-06-09BN51878VOC1ND
2016-07-15BN73865VOC1ND
2016-08-18BN94948TTHM22.0 ppb
2016-08-18BN94949TTHM46.0 ppb
2016-08-18BN94950TTHM7.80 ppb
2016-08-18BN94951TTHM23.0 ppb
2016-08-18BN94952TTHM43.0 ppb
2016-08-18BN94953TTHM6.70 ppb
2016-08-18BN94954TTHM26.0 ppb
2016-08-18BN94955TTHM16.0 ppb
2016-11-03BV75338TTHM8.50 ppb
2016-11-03BV75339TTHM40.0 ppb
2016-11-03BV75340TTHM15.0 ppb
2016-11-03BV75341TTHM11.0 ppb
2016-11-03BV75342TTHM37.0 ppb
2016-11-03BV75343TTHM7.40 ppb
2016-11-03BV75344TTHM8.00 ppb
2016-11-03BV75345TTHM10.00 ppb
2017-02-02BX44867TTHM7.10 ppb
2017-02-02BX44868TTHM33.0 ppb
2017-02-02BX44869TTHM23.0 ppb
2017-02-02BX44870TTHM16.0 ppb
2017-02-02BX44871TTHM34.0 ppb
2017-02-02BX44872TTHM5.90 ppb
2017-02-02BX44873TTHM9.80 ppb
2017-02-02BX44874TTHM11.0 ppb
2017-02-08BX57435VOC16.20 ppb
2017-03-03BX79851VOC1ND
2017-03-03BX79849VOC1ND
2017-04-21BY07962VOC1ND
2017-05-04BY15439TTHM8.10 ppb
2017-05-04BY15440TTHM45.0 ppb
2017-05-04BY15441TTHM11.0 ppb
2017-05-04BY15442TTHM23.0 ppb
2017-05-04BY15443TTHM46.0 ppb
2017-05-04BY15444TTHM7.50 ppb
2017-05-04BY15445TTHM19.0 ppb
2017-05-04BY15446TTHM19.0 ppb
2017-06-01BY32099VOC1ND
2017-07-07BY54441VOC1ND
2017-08-07BY79801TTHM23.0 ppb
2017-08-07BY79802TTHM31.0 ppb
2017-08-07BY79803TTHM21.0 ppb
2017-08-07BY79804TTHM22.0 ppb
2017-08-07BY79805TTHM33.0 ppb
2017-08-07BY79806TTHM23.0 ppb
2017-08-07BY79807TTHM20.0 ppb
2017-08-07BY79808TTHM17.0 ppb
2017-11-06BZ33918TTHM36.0 ppb
2017-11-16BZ43465TTHM36.0 ppb
2017-11-16BZ43466TTHM62.0 ppb
2017-11-16BZ43467TTHM57.0 ppb
2017-11-16BZ43468TTHM50.0 ppb
2017-11-16BZ43469TTHM28.0 ppb
2017-11-16BZ43470TTHM32.0 ppb
2017-11-16BZ43471TTHM26.0 ppb
2018-01-23BZ78888VOC110.00 ppb
2018-01-31BZ82950VOC1ND
2018-02-01BZ83504TTHM28.0 ppb
2018-02-01BZ83505TTHM42.0 ppb
2018-02-01BZ83506TTHM38.0 ppb
2018-02-01BZ83507TTHM48.0 ppb
2018-02-01BZ83508TTHM17.0 ppb
2018-02-01BZ83509TTHM20.0 ppb
2018-02-01BZ83510TTHM18.0 ppb
2018-02-21BZ93283TTHM22.0 ppb
2018-05-03CA41161TTHM26.0 ppb
2018-05-03CA41162TTHM49.0 ppb
2018-05-03CA41163TTHM42.0 ppb
2018-05-03CA41164TTHM54.0 ppb
2018-05-03CA41165TTHM13.0 ppb
2018-05-03CA41166TTHM18.0 ppb
2018-05-03CA41167TTHM19.0 ppb
2018-05-03D8E0468-01VOC48.9 ppb
2018-05-15CA48118TTHM33.0 ppb
2018-07-13CA89901ND
2018-08-02CB0402031.0 ppb
2018-08-02CB0402182.0 ppb
2018-08-02CB0402248.0 ppb
2018-08-02CB0402364.0 ppb
2018-08-02CB0402426.0 ppb
2018-08-02CB0402538.0 ppb
2018-08-02CB0402639.0 ppb
2018-08-06CB0584043.0 ppb
2018-08-10DBP 20050203163.7 ppb
2018-08-10CB0915468.0 ppb
2018-11-01DBP 20051113336.2 ppb
2018-11-01DBP 20051113453.8 ppb
2018-11-01DBP 20051113555.9 ppb
2018-11-01DBP 20051113662.4 ppb
2018-11-01DBP 20051113720.6 ppb
2018-11-01DBP 20051113812.4 ppb
2018-11-01DBP 20051113915.3 ppb
2018-11-05DBP 20051138921.5 ppb
2019-01-02VOC1 2005173097.90 ppb
2019-02-07DBP 2005210838.60 ppb
2019-02-07DBP 20052108429.1 ppb
2019-02-07DBP 2005210858.90 ppb
2019-02-07DBP 20052108624.9 ppb
2019-02-07DBP 2005210878.90 ppb
2019-02-07DBP 20052108831.3 ppb
2019-02-07DBP 20052108919.8 ppb
2019-02-11DBP 20052125613.1 ppb
2019-03-15VOC1 200524883ND
2019-05-09DBP 20053157522.1 ppb
2019-05-09DBP 20053157646.8 ppb
2019-05-09DBP 20053157743.0 ppb
2019-05-09DBP 20053158251.0 ppb
2019-05-09DBP 20053158413.9 ppb
2019-05-09DBP 20053158612.8 ppb
2019-05-09DBP 20053158712.7 ppb
2019-05-13DBP 20053183719.9 ppb
2019-08-01DBP 20054272219.9 ppb
2019-08-01DBP 20054272333.7 ppb
2019-08-01DBP 20054272422.4 ppb
2019-08-01DBP 20054272549.0 ppb
2019-08-01DBP 20054272625.2 ppb
2019-08-01DBP 20054272716.2 ppb
2019-08-01DBP 20054272814.9 ppb
2019-08-13DBP 20054475834.6 ppb
2019-11-07DBP 20055582845.7 ppb
2019-11-07DBP 20055583050.1 ppb
2019-11-07DBP 20055583143.4 ppb
2019-11-07DBP 20055583249.3 ppb
2019-11-07DBP 20055583332.7 ppb
2019-11-07DBP 20055583418.3 ppb
2019-11-07DBP 20055583514.7 ppb
2019-11-18DBP 20055700421.6 ppb