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EWG's Tap Water Database — 2021 UPDATE

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Nitrite

City of Madison

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.

 

22

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2014ND30ND
2015ND30ND
2016ND40ND
2017ND40ND
2018ND40ND
2019ND40ND

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
2014-04-16140417-103NIND
2014-04-16140417-102NIND
2014-04-16140417-101NIND
2015-05-06150507-079NIND
2015-05-06150507-078NIND
2015-05-06150507-070NIND
2016-04-26160426-005NIND
2016-04-26160426-004NIND
2016-04-26160426-003NIND
2016-11-28161128-001NIND
2017-03-06170307-050NIND
2017-03-06170307-040NIND
2017-03-06170307-034NIND
2017-03-06170307-033NIND
2018-03-06180307-032NIND
2018-03-06180307-031NIND
2018-03-06180307-029NIND
2018-03-06180307-028NIND
2019-02-26190227-027NIND
2019-02-26190227-060NIND
2019-02-26190227-044NIND
2019-02-26190227-037NIND