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EWG's Tap Water Database — 2021 UPDATE

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Arsenic

Southwest Ouachita Waterworks Inc.

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.

 

28

Samples

0

Samples exceeding legal limit (MCL)

4

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20140.167 ppb122ND - 1.000 ppb
2015ND20ND
2016N/A00N/A
20170.0843 ppb142ND - 0.590 ppb
2018N/A00N/A
2019N/A00N/A

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
2014-06-16AD92407ND
2014-06-16AD92402ND
2014-06-16AD92407ND
2014-06-16AD92402ND
2014-10-20AD98771ND
2014-10-20AD98761ND
2014-10-20AD987661.000 ppb
2014-10-20AD98771ND
2014-10-20AD98776ND
2014-10-20AD987661.000 ppb
2014-10-20AD98761ND
2014-10-20AD98776ND
2015-01-05AE00852ND
2015-01-05AE00852ND
2017-06-1235318592003ND
2017-06-1235318592002ND
2017-06-12353185920010.590 ppb
2017-06-12353185920010.590 ppb
2017-06-1235318592002ND
2017-06-1235318592003ND
2017-10-1635343270001ND
2017-10-1635343270004ND
2017-10-1635343270003ND
2017-10-1635343270002ND
2017-10-1635343270001ND
2017-10-1635343270004ND
2017-10-1635343270003ND
2017-10-1635343270002ND