Menu

EWG's Tap Water Database — 2021 UPDATE

Donate

Chloroform

SJWTX Triple Peak Plant

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

 

144

Samples

0

Samples exceeding legal limit (MCL)

95

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2013N/A00N/A
20146.94 ppb2216ND - 19.9 ppb
201517.1 ppb2215ND - 79.1 ppb
20162.85 ppb2313ND - 34.6 ppb
20173.71 ppb2816ND - 14.0 ppb
20184.31 ppb2515ND - 12.6 ppb
20198.63 ppb2420ND - 17.6 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
2014-02-18AC4333210.1 ppb
2014-02-18AC43327ND
2014-02-18AC4330912.9 ppb
2014-02-18AC4331911.3 ppb
2014-03-31AC486941.30 ppb
2014-04-17AC51098ND
2014-04-17AC510346.20 ppb
2014-04-17AC51055ND
2014-04-17AC510567.90 ppb
2014-04-17AC5105711.8 ppb
2014-06-24AC57812ND
2014-06-24AC57804ND
2014-06-24AC57808ND
2014-07-24AC608876.00 ppb
2014-07-24AC6093911.3 ppb
2014-07-24AC6093613.3 ppb
2014-07-24AC6095211.6 ppb
2014-07-24AC6093719.9 ppb
2014-11-14AC721595.10 ppb
2014-11-14AC721601.30 ppb
2014-11-14AC721845.70 ppb
2014-11-14AC7214216.9 ppb
2015-01-16AC769457.80 ppb
2015-01-16AC76935ND
2015-01-16AC769394.40 ppb
2015-01-16AC769275.20 ppb
2015-06-03AC94415ND
2015-06-03AC94433ND
2015-06-03AC94413ND
2015-06-03AC94443ND
2015-06-03AC943701.90 ppb
2015-06-03AC94371ND
2015-06-03AC943691.70 ppb
2015-06-03AC943722.20 ppb
2015-08-05AD0266138.0 ppb
2015-08-05AD0257944.6 ppb
2015-08-05AD0257837.0 ppb
2015-08-05AD0258756.3 ppb
2015-08-05AD0257779.1 ppb
2015-11-03AD1234530.0 ppb
2015-11-03AD12384ND
2015-11-03AD1244431.2 ppb
2015-11-03AD1238734.2 ppb
2015-11-03AD124011.90 ppb
2016-01-26AD201061.80 ppb
2016-01-26AD20098ND
2016-01-26AD20094ND
2016-01-26AD200403.40 ppb
2016-01-26AD20057ND
2016-01-26AD2004611.6 ppb
2016-01-26AD2003134.6 ppb
2016-04-22AD33995ND
2016-04-22AD339401.10 ppb
2016-04-22AD33942ND
2016-04-22AD339431.10 ppb
2016-04-22AD33941ND
2016-07-26AD45721ND
2016-07-26AD45733ND
2016-07-26AD456681.60 ppb
2016-07-26AD45669ND
2016-07-26AD456771.90 ppb
2016-07-26AD456701.000 ppb
2016-10-04AD524261.90 ppb
2016-10-04AD524331.50 ppb
2016-10-04AD524302.00 ppb
2016-10-04AD524292.00 ppb
2016-12-01AD59882ND
2017-02-01AD68127ND
2017-02-01AD68121ND
2017-02-01AD68061ND
2017-02-01AD68051ND
2017-02-01AD680592.70 ppb
2017-02-01AD680504.20 ppb
2017-05-03AD82809ND
2017-05-03AD82811ND
2017-05-03AD827071.40 ppb
2017-05-03AD827067.00 ppb
2017-05-03AD827087.60 ppb
2017-05-31AD86159ND
2017-05-31AD86143ND
2017-05-31AD86145ND
2017-05-31AD86169ND
2017-06-26AD878051.10 ppb
2017-06-26AD87809ND
2017-06-26AD877777.10 ppb
2017-07-27AD91116ND
2017-07-27AD911247.20 ppb
2017-07-27AD910368.80 ppb
2017-07-27AD910379.40 ppb
2017-07-27AD910409.00 ppb
2017-07-27AD9105014.0 ppb
2017-11-27AE057271.80 ppb
2017-11-27AE057287.70 ppb
2017-11-27AE057296.50 ppb
2017-11-27AE057308.40 ppb
2018-02-06AE124684.40 ppb
2018-02-06AE12467ND
2018-02-06AE124656.70 ppb
2018-02-06AE124748.20 ppb
2018-04-23AE23479ND
2018-04-23AE23473ND
2018-04-23AE234295.00 ppb
2018-04-23AE234417.10 ppb
2018-04-23AE234306.90 ppb
2018-04-23AE2343510.1 ppb
2018-06-20AE30756ND
2018-06-20AE30750ND
2018-06-20AE30754ND
2018-06-20AE30798ND
2018-07-24AE343437.90 ppb
2018-07-24AE342796.80 ppb
2018-07-24AE342781.10 ppb
2018-07-24AE342809.90 ppb
2018-07-24AE3427712.6 ppb
2018-08-27AE38540ND
2018-11-06AE453666.50 ppb
2018-11-06AE45368ND
2018-11-06AE453717.00 ppb
2018-11-06AE453677.50 ppb
2018-11-06AE45441ND
2019-02-12AE54211ND
2019-02-12AE542091.10 ppb
2019-02-12AE5420417.6 ppb
2019-02-12AE5420710.00 ppb
2019-02-12AE542058.30 ppb
2019-02-12AE5420614.8 ppb
2019-05-22AE676894.80 ppb
2019-05-22AE67687ND
2019-05-22AE67685ND
2019-05-22AE67691ND
2019-05-22AE6765716.9 ppb
2019-05-22AE6765910.2 ppb
2019-05-22AE6765813.8 ppb
2019-05-22AE6765613.6 ppb
2019-06-18AE711282.10 ppb
2019-07-01AE728548.40 ppb
2019-07-01AE728089.70 ppb
2019-07-01AE7280310.6 ppb
2019-07-01AE7280412.1 ppb
2019-07-01AE7280514.4 ppb
2019-10-15AE867358.70 ppb
2019-10-15AE867367.10 ppb
2019-10-15AE8673310.9 ppb
2019-10-15AE8673411.9 ppb