Menu

EWG's Tap Water Database — 2021 UPDATE

Donate

Nitrite

Maryland American Water Company

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.

 

12

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2014ND20ND
2015ND20ND
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
2014-05-13140513_01_256765ND
2014-05-13140513_02_256717ND
2015-05-1228898401ND
2015-05-1328900001ND
2016-05-1031992801ND
2016-05-1031991701ND
2017-05-0935398101ND
2017-05-0935392601ND
2018-05-1539313001ND
2018-05-1539310501ND
2019-05-1643893401ND
2019-05-2143893501ND