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EWG's Tap Water Database — 2021 UPDATE

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Chloroform

Sharyland Water Supply Corporation

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

 

115

Samples

0

Samples exceeding legal limit (MCL)

99

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2013N/A00N/A
20141.15 ppb1814ND - 2.10 ppb
20151.18 ppb1814ND - 2.30 ppb
20161.18 ppb2217ND - 2.00 ppb
20171.72 ppb1916ND - 3.70 ppb
20182.95 ppb19191.40 ppb - 6.20 ppb
20192.78 ppb19191.80 ppb - 5.60 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
2014-03-18AC47342ND
2014-03-18AC47343ND
2014-03-18AC47344ND
2014-03-18AC47345ND
2014-05-05AC529721.000 ppb
2014-05-05AC529761.20 ppb
2014-05-05AC529751.000 ppb
2014-05-05AC529701.30 ppb
2014-08-19AC643261.80 ppb
2014-08-19AC643001.70 ppb
2014-08-19AC644201.40 ppb
2014-08-19AC644332.10 ppb
2014-08-19AC644291.90 ppb
2014-08-19AC644181.90 ppb
2014-10-10AC694961.30 ppb
2014-10-10AC694801.40 ppb
2014-10-10AC694811.40 ppb
2014-10-10AC694981.30 ppb
2015-02-05AC79442ND
2015-02-05AC79446ND
2015-02-05AC79449ND
2015-02-05AC79448ND
2015-05-05AC904932.30 ppb
2015-05-05AC904851.40 ppb
2015-05-05AC904701.20 ppb
2015-05-05AC904971.60 ppb
2015-08-03AD021291.80 ppb
2015-08-03AD021311.70 ppb
2015-08-03AD019991.000 ppb
2015-08-03AD020031.40 ppb
2015-08-03AD020531.70 ppb
2015-08-03AD020001.40 ppb
2015-11-04AD125801.30 ppb
2015-11-04AD126111.10 ppb
2015-11-04AD126031.60 ppb
2015-11-04AD125921.70 ppb
2016-02-03AD21771ND
2016-02-03AD21775ND
2016-02-03AD21773ND
2016-02-03AD217701.60 ppb
2016-03-23AD301491.50 ppb
2016-05-11AD363021.80 ppb
2016-05-11AD363081.40 ppb
2016-05-11AD363091.60 ppb
2016-05-11AD363962.00 ppb
2016-06-06AD393771.90 ppb
2016-09-14AD49452ND
2016-09-14AD494881.60 ppb
2016-09-14AD493821.10 ppb
2016-09-14AD493831.000 ppb
2016-09-14AD493791.10 ppb
2016-09-14AD493781.50 ppb
2016-09-14AD494501.40 ppb
2016-10-26AD551281.60 ppb
2016-10-26AD551301.30 ppb
2016-10-26AD55120ND
2016-10-26AD551211.70 ppb
2016-10-26AD551471.90 ppb
2017-03-09AD74641ND
2017-03-09AD746331.10 ppb
2017-03-10AD74642ND
2017-03-10AD74645ND
2017-04-25AD814902.10 ppb
2017-04-25AD814831.90 ppb
2017-04-25AD814861.90 ppb
2017-04-25AD814911.60 ppb
2017-08-02AD921601.70 ppb
2017-08-02AD921561.30 ppb
2017-08-02AD921581.20 ppb
2017-08-02AD921351.30 ppb
2017-08-02AD921431.10 ppb
2017-08-02AD921441.30 ppb
2017-08-02AD921401.60 ppb
2017-11-10AE044913.70 ppb
2017-11-10AE044933.50 ppb
2017-11-10AE044903.70 ppb
2017-11-10AE044893.70 ppb
2018-03-07AE175332.70 ppb
2018-03-07AE175323.20 ppb
2018-03-07AE175312.80 ppb
2018-03-07AE175305.50 ppb
2018-05-16AE267403.20 ppb
2018-05-16AE267343.40 ppb
2018-05-16AE267434.00 ppb
2018-05-16AE267376.20 ppb
2018-08-28AE386551.70 ppb
2018-08-28AE386572.00 ppb
2018-08-28AE386562.00 ppb
2018-08-28AE386583.10 ppb
2018-08-31AE391552.90 ppb
2018-08-31AE391452.10 ppb
2018-08-31AE391474.20 ppb
2018-12-05AE481801.50 ppb
2018-12-05AE481761.60 ppb
2018-12-05AE481782.50 ppb
2018-12-05AE481731.40 ppb
2019-01-16AE500792.60 ppb
2019-01-16AE500832.50 ppb
2019-01-16AE500815.60 ppb
2019-01-16AE500965.20 ppb
2019-06-24AE717653.10 ppb
2019-06-24AE716711.80 ppb
2019-06-24AE716702.40 ppb
2019-06-24AE716732.60 ppb
2019-06-24AE716693.10 ppb
2019-09-18AE839721.90 ppb
2019-09-18AE839742.50 ppb
2019-09-18AE839562.30 ppb
2019-09-18AE839582.50 ppb
2019-09-18AE839542.50 ppb
2019-09-18AE839554.20 ppb
2019-12-05AE914262.00 ppb
2019-12-05AE914241.90 ppb
2019-12-05AE914232.00 ppb
2019-12-05AE914222.20 ppb