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EWG's Tap Water Database — 2021 UPDATE

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Arsenic

Los Angeles, City Of - Power Plant #1

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

 

73

Samples

1

Samples exceeding legal limit (MCL)

7

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20142.11 ppb135ND - 10.7 ppb
2015ND120ND
2016ND120ND
2017ND120ND
2018ND120ND
20190.408 ppb122ND - 3.60 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
2014-01-081200-002-0935ND
2014-02-051200-002-1140ND
2014-03-051200-002-0935ND
2014-04-091200-002-0940ND
2014-05-131200-002-10552.50 ppb
2014-06-121200-002-12302.30 ppb
2014-07-091200-002-091010.7 ppb
2014-07-141200-002-07507.00 ppb
2014-07-171200-002-07254.90 ppb
2014-09-111200-002-0940ND
2014-10-091200-002-0935ND
2014-11-101200-002-1100ND
2014-12-101200-002-1030ND
2015-01-081200-002-0925ND
2015-02-051200-002-1005ND
2015-03-051200-002-0835ND
2015-04-071200-002-0845ND
2015-05-051200-002-1000ND
2015-06-101200-002-0835ND
2015-07-081200-002-0845ND
2015-08-181200-002-1005ND
2015-09-021200-002-1100ND
2015-10-071200-002-0900ND
2015-11-051200-002-0835ND
2015-12-091200-002-0940ND
2016-01-081200-002-0850ND
2016-02-031200-002-0955ND
2016-03-101200-002-0905ND
2016-04-071200-002-0855ND
2016-05-051200-002-0845ND
2016-06-101200-002-1040ND
2016-07-071200-002-0855ND
2016-08-041200-002-0935ND
2016-09-091200-002-1205ND
2016-10-061200-002-1040ND
2016-11-081200-002-0930ND
2016-12-121200-002-0945ND
2017-01-231200-002-0945ND
2017-02-271200-002-1030ND
2017-03-201200-002-0926ND
2017-04-171200-002-1040ND
2017-05-221200-002-1129ND
2017-06-121200-002-1215ND
2017-07-151200-002-0912ND
2017-08-151200-002-1315ND
2017-09-091200-002-0945ND
2017-10-071200-002-1030ND
2017-11-221200-002-0923ND
2017-12-201200-002-0818ND
2018-01-221200-002-0830ND
2018-02-201200-002-0836ND
2018-03-191200-002-0936ND
2018-04-231200-002-0845ND
2018-05-211200-002-1053ND
2018-06-181200-002-0812ND
2018-07-231200-002-0900ND
2018-08-211200-002-1105ND
2018-09-241200-002-1056ND
2018-10-221200-002-0758ND
2018-11-191200-002-0908ND
2018-12-171200-002-0920ND
2019-01-221200-002-0908ND
2019-02-061200-002-1011ND
2019-03-041200-002-1012ND
2019-04-011200-002-1103ND
2019-05-061200-002-0930ND
2019-06-031200-002-1029ND
2019-07-011200-002-0940ND
2019-08-051200-002-0958ND
2019-09-091200-002-10181.30 ppb
2019-10-071200-002-10373.60 ppb
2019-11-041200-002-1122ND
2019-12-021200-002-1015ND