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EWG's Tap Water Database — 2021 UPDATE

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Arsenic

Calico Rock

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.

MORE ABOUT THIS CONTAMINANT

 

60

Samples

0

Samples exceeding legal limit (MCL)

12

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20140.400 ppb61ND - 2.40 ppb
20150.957 ppb73ND - 2.30 ppb
20160.154 ppb131ND - 2.00 ppb
20170.314 ppb142ND - 2.30 ppb
20180.860 ppb104ND - 2.30 ppb
20190.220 ppb101ND - 2.20 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
2014-01-241403000542.40 ppb
2014-05-27141500004ND
2014-08-25Y142390011ND
2014-08-25Y142400016ND
2014-08-25Y142390010ND
2014-10-14Y142890008ND
2015-01-13Y1501600052.30 ppb
2015-04-14Y151060032ND
2015-08-19Y152320001ND
2015-08-19Y1523200042.30 ppb
2015-08-19Y152320003ND
2015-08-19Y152320002ND
2015-10-14Y1528900122.10 ppb
2016-01-13Y1601500512.00 ppb
2016-02-16Y160500006ND
2016-04-12Y161060006ND
2016-04-12Y161060004ND
2016-07-12Y161970004ND
2016-07-12Y161970005ND
2016-07-12Y161970006ND
2016-08-30Y162450007ND
2016-09-26Y162730003ND
2016-10-11Y162870014ND
2016-10-11Y162880009ND
2016-10-11Y162880011ND
2016-12-13Y163510003ND
2017-01-10Y170130010ND
2017-01-10Y170130011ND
2017-01-10Y1701300172.30 ppb
2017-04-11Y171030029ND
2017-04-11Y171030023ND
2017-04-11Y171030020ND
2017-07-11Y171950130ND
2017-07-11Y171950137ND
2017-07-11Y171950139ND
2017-08-15Y172290006ND
2017-08-15Y172290007ND
2017-10-10Y172850031ND
2017-10-10Y1728500352.10 ppb
2017-10-10Y172850036ND
2018-01-30Y180330005ND
2018-01-30Y1803300092.00 ppb
2018-04-11Y1810200262.10 ppb
2018-09-12Y182560026ND
2018-09-12Y1825600282.30 ppb
2018-09-12Y182560025ND
2018-09-12Y182560027ND
2018-10-09Y1828400472.20 ppb
2018-10-09Y182840046ND
2018-11-19Y183250008ND
2019-01-15Y190180011ND
2019-01-15Y190180012ND
2019-04-09Y191010046ND
2019-04-09Y191010041ND
2019-08-26Y192410001ND
2019-08-26Y192410002ND
2019-08-26Y192410026ND
2019-10-08Y192840019ND
2019-10-08Y1928400182.20 ppb
2019-10-08Y192840024ND