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EWG's Tap Water Database — 2019 UPDATE

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Chloroform

SBNDO County Service Area 70J

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.

 

61

Samples

0

Samples exceeding legal limit (MCL)

9

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2012ND30ND
2013ND10ND
2014ND50ND
20150.340 ppb203ND - 3.20 ppb
20160.200 ppb163ND - 1.20 ppb
20170.225 ppb163ND - 1.40 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
2012-01-063761-005-1035ND
2012-01-133761-003-0950ND
2012-10-263761-002-1035ND
2013-10-183761-005-1020ND
2014-02-033761-005-1345ND
2014-02-033761-003-0930ND
2014-02-033761-002-1030ND
2014-02-033761-001-1130ND
2014-02-043761-004-1300ND
2015-01-063761-002-1350ND
2015-01-063761-003-1425ND
2015-01-063761-005-1210ND
2015-01-123761-604-1105ND
2015-01-123761-603-1140ND
2015-01-123761-602-1030ND
2015-01-123761-601-12303.20 ppb
2015-04-083761-601-10302.10 ppb
2015-04-083761-602-1305ND
2015-04-083761-604-1345ND
2015-04-083761-603-1135ND
2015-07-093761-602-1335ND
2015-07-093761-604-1300ND
2015-07-093761-601-11301.50 ppb
2015-07-093761-603-1220ND
2015-07-293761-004-1000ND
2015-10-133761-604-1220ND
2015-10-133761-603-1015ND
2015-10-133761-601-1100ND
2015-10-133761-602-1135ND
2016-01-113761-604-1130ND
2016-01-113761-601-09501.000 ppb
2016-01-113761-603-1045ND
2016-01-113761-602-1215ND
2016-04-113761-602-1150ND
2016-04-113761-601-12201.000 ppb
2016-04-133761-604-0950ND
2016-04-133761-603-0930ND
2016-07-143761-604-1330ND
2016-07-143761-601-1130ND
2016-07-143761-603-1300ND
2016-07-143761-602-1200ND
2016-10-113761-603-1245ND
2016-10-113761-601-10501.20 ppb
2016-10-113761-604-1325ND
2016-10-113761-602-1120ND
2017-01-103761-603-1240ND
2017-01-103761-604-1320ND
2017-01-103761-601-11001.000 ppb
2017-01-103761-602-1130ND
2017-04-113761-601-1020ND
2017-04-113761-603-1230ND
2017-04-113761-602-1140ND
2017-04-113761-604-1300ND
2017-07-103761-601-10301.20 ppb
2017-07-103761-602-1115ND
2017-07-103761-603-1230ND
2017-07-263761-001-1300ND
2017-10-113761-601-14001.40 ppb
2017-10-113761-604-1145ND
2017-10-113761-602-1320ND
2017-10-113761-603-1215ND