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EWG's Tap Water Database — 2019 UPDATE

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Trichloroacetic acid

Contra Costa Water District

Trichloroacetic acid, one of the group of five haloacetic acids regulated by federal standards, is formed when chlorine or other disinfectants are used to treat drinking water. Haloacetic acids and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Click here to read more about disinfection byproducts.

 

16

Samples

0

Samples exceeding legal limit (MCL)

2

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2012ND10ND
20130.250 ppb41ND - 1.000 ppb
2014ND40ND
2015ND20ND
2016ND30ND
20172.10 ppb21ND - 4.20 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 0.1 ppb

The EWG Health Guideline of 0.1 ppb for trichloroacetic acid was proposed in 2020 by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk.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
2012-09-049590-003-0745ND
2013-03-209590-003-12551.000 ppb
2013-06-049590-003-1345ND
2013-09-039590-003-0910ND
2013-12-039590-003-0805ND
2014-03-109590-003-1119ND
2014-06-039590-003-1445ND
2014-09-029590-003-1500ND
2014-12-029590-003-1345ND
2015-06-029590-003-0815ND
2015-12-019590-003-1515ND
2016-06-079590-003-0851ND
2016-09-069590-003-0823ND
2016-12-069590-003-0915ND
2017-06-069590-003-13154.20 ppb
2017-09-129590-003-1420ND