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EWG's Tap Water Database — 2021 UPDATE

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Nitrite

Golden State Water Company - Cowan Heights

Nitrite, closely related to the fertilizer chemical nitrate, comes from urban runoff and from fertilizer applied to agricultural lands to pollute drinking water. Nitrite is significantly more toxic than nitrate. Excessive nitrite in water can cause oxygen deprivation in infants and increase the risk of cancer.

MORE ABOUT THIS CONTAMINANT

 

26

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2014ND140ND
2015ND40ND
2016ND20ND
2017ND20ND
2018ND20ND
2019ND20ND

ppm = parts per million

State and national drinking water standards and health guidelines

EPA Maximum Contaminant
Level (MCL) 1 ppm

The legal limit for nitrite, established in 1991, was based on the rate of conversion of ingested nitrate into nitrite in adults. This limit may not fully protect against the risk of cancer due to nitrite exposure.

ppm = parts per million

All test results

Date Lab ID Result
2014-01-072706-001-0830ND
2014-02-182706-001-1410ND
2014-02-194417-004-0925ND
2014-02-194417-001-0940ND
2014-03-042706-001-1200ND
2014-04-072706-001-0815ND
2014-05-052706-001-0850ND
2014-06-022706-001-1045ND
2014-07-072706-001-1330ND
2014-08-042706-001-0850ND
2014-09-022706-001-1005ND
2014-10-062706-001-0905ND
2014-11-032706-001-0800ND
2014-12-012706-001-0825ND
2015-01-052706-001-0915ND
2015-02-024417-001-0830ND
2015-02-022706-001-1310ND
2015-02-024417-004-0850ND
2016-01-194417-001-0835ND
2016-01-194417-004-0850ND
2017-01-104417-004-0940ND
2017-01-104417-001-0925ND
2018-01-084417-004-0905ND
2018-01-084417-001-0930ND
2019-03-254417-004-0840ND
2019-03-254417-001-0855ND