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EWG's Tap Water Database — 2019 UPDATE

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Arsenic

California Water Service Company - Dominguez

Arsenic is a potent carcinogen and common contaminant in drinking water. Arsenic causes thousands of cases of cancer each year in the U.S. Click here to read more about arsenic.

 

23

Samples

0

Samples exceeding legal limit (MCL)

1

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2012ND10ND
2013ND60ND
20141.20 ppb31ND - 3.60 ppb
2015ND10ND
2016ND60ND
2017ND60ND

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 0.004 ppb

The EWG Health Guideline of 0.004 ppb for arsenic was defined 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. This health guideline protects against cancer.

EPA Maximum Contaminant
Level (MCL) 10 ppb

The legal limit for arsenic, established in 2001, was based on costs for arsenic removal, as calculated at the time that the standard was set. This limit does not fully protect against the risk of cancer due to arsenic exposure.

ppb = parts per billion

All test results

Date Lab ID Result
2012-08-205810-018-1124ND
2013-03-135810-024-1047ND
2013-05-085810-036-1143ND
2013-06-185810-023-1312ND
2013-07-175810-050-1442ND
2013-09-195810-004-1430ND
2013-10-165810-022-1400ND
2014-07-095701-050-13403.60 ppb
2014-08-275810-016-1310ND
2014-10-085810-019-1022ND
2015-03-259590-018-1355ND
2016-01-135810-023-1320ND
2016-03-239590-018-1340ND
2016-05-115810-036-1140ND
2016-07-135810-050-1335ND
2016-09-075810-004-1300ND
2016-12-289590-019-0930ND
2017-03-089590-019-1430ND
2017-08-235810-019-1100ND
2017-08-235810-016-1212ND
2017-10-119590-036-1335ND
2017-10-169590-805-1030ND
2017-12-265810-024-1315ND