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EWG's Tap Water Database — 2021 UPDATE

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Nitrite

Norman

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

 

76

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2013N/A00N/A
20140.00716 ppm283ND - 0.0820 ppm
2015ND120ND
20160.208 ppm21ND - 0.415 ppm
20170.00257 ppm324ND - 0.0351 ppm
2018N/A00N/A
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
2014-07-231320267ND
2014-07-231320266ND
2014-07-231320265ND
2014-07-231320264ND
2014-07-231320263ND
2014-07-301322172ND
2014-10-2913460330.0820 ppm
2014-10-291346027ND
2014-10-2913460280.0683 ppm
2014-10-2913460290.0503 ppm
2014-10-291346030ND
2014-10-291346035ND
2014-10-291346036ND
2014-10-291346037ND
2014-10-291346038ND
2014-11-181351366ND
2014-11-181351364ND
2014-11-191351786ND
2014-11-191351768ND
2014-11-191351773ND
2014-11-191351777ND
2014-11-191351778ND
2014-11-191351782ND
2014-11-191351784ND
2014-11-191351785ND
2014-11-191351787ND
2014-12-151357749ND
2014-12-171359089ND
2015-03-031376050ND
2015-03-031376049ND
2015-03-031376048ND
2015-03-031376047ND
2015-03-031376046ND
2015-06-151402904ND
2015-07-141410566ND
2015-07-141410565ND
2015-07-141410562ND
2015-08-111418115ND
2015-10-201437078ND
2015-12-151451835ND
2016-09-2215270570.415 ppm
2016-09-231527055ND
2017-02-091562571ND
2017-02-091562572ND
2017-02-091562573ND
2017-02-0915625740.0146 ppm
2017-03-091570619ND
2017-03-091570618ND
2017-03-091570617ND
2017-03-091570616ND
2017-03-091570615ND
2017-03-231574298ND
2017-03-231574297ND
2017-03-231574299ND
2017-03-231574300ND
2017-03-231574304ND
2017-03-231574305ND
2017-03-231574301ND
2017-03-301575713ND
2017-04-041576613ND
2017-04-041576612ND
2017-06-081594969ND
2017-06-081594966ND
2017-06-081594970ND
2017-06-081594971ND
2017-06-081594972ND
2017-07-1116031470.0134 ppm
2017-07-1116031460.0192 ppm
2017-08-021622976ND
2017-10-091628535ND
2017-10-091628533ND
2017-10-091628530ND
2017-10-0916285200.0351 ppm
2017-11-131638065ND
2019-06-05BF06058-06ND
2019-06-05BF06058-07ND