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EWG's Tap Water Database — 2021 UPDATE

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Arsenic

SJWTX Triple Peak Plant

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.

 

31

Samples

0

Samples exceeding legal limit (MCL)

5

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2013N/A00N/A
2014ND20ND
20150.575 ppb41ND - 2.30 ppb
20160.725 ppb82ND - 3.20 ppb
20170.700 ppb61ND - 4.20 ppb
2018ND40ND
20190.771 ppb71ND - 5.40 ppb

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
2014-03-31AC48683ND
2014-06-24AC57769ND
2015-01-16AC76741ND
2015-06-03AC943482.30 ppb
2015-06-03AC94344ND
2015-11-03AD12300ND
2016-01-26AD199902.60 ppb
2016-01-26AD19996ND
2016-01-26AD19991ND
2016-01-26AD19989ND
2016-03-18AD295433.20 ppb
2016-03-18AD29527ND
2016-03-18AD29542ND
2016-12-01AD59772ND
2017-02-01AD68016ND
2017-02-01AD68015ND
2017-05-03AD82651ND
2017-05-31AD860744.20 ppb
2017-05-31AD86073ND
2017-05-31AD86075ND
2018-02-06AE12409ND
2018-04-23AE23410ND
2018-06-20AE30653ND
2018-09-11AE39521ND
2019-02-12AE54201ND
2019-02-12AE54202ND
2019-05-22AE67565ND
2019-05-22AE67566ND
2019-06-18AE71008ND
2019-09-19AE84030ND
2019-10-15AE867275.40 ppb