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EWG's Tap Water Database — 2019 UPDATE

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Nitrite

City of Houston

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.

 

104

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2012ND300ND
20130.00417 ppm367ND - 0.0400 ppm
2014ND90ND
20150.000357 ppm281ND - 0.01000 ppm
2016N/A00N/A
2017ND10ND

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
2012-04-10AB86369ND
2012-04-10AB86366ND
2012-04-10AB86370ND
2012-04-10AB86368ND
2012-05-23AB90553ND
2012-05-23AB90561ND
2012-05-23AB90560ND
2012-05-23AB90552ND
2012-05-23AB90546ND
2012-05-23AB90566ND
2012-05-23AB90562ND
2012-06-12AB92262ND
2012-06-12AB92266ND
2012-06-12AB92265ND
2012-06-12AB92263ND
2012-06-12AB92261ND
2012-07-24AB96026ND
2012-07-24AB96021ND
2012-07-24AB96018ND
2012-07-24AB96017ND
2012-07-24AB96019ND
2012-07-24AB96016ND
2012-07-24AB96020ND
2012-11-19AC05374ND
2012-11-19AC05379ND
2012-11-19AC05378ND
2012-11-19AC05375ND
2012-11-19AC05376ND
2012-11-19AC05373ND
2012-11-19AC05377ND
2013-02-26AC11494ND
2013-06-13AC219690.0200 ppm
2013-06-13AC219700.01000 ppm
2013-08-08AC271510.0200 ppm
2013-08-08AC271500.0300 ppm
2013-08-08AC27149ND
2013-08-08AC27152ND
2013-08-08AC27146ND
2013-08-08AC271470.01000 ppm
2013-08-08AC271480.0200 ppm
2013-09-25AC31236ND
2013-09-25AC31238ND
2013-09-25AC31251ND
2013-10-24AC33156ND
2013-10-24AC33155ND
2013-10-24AC33158ND
2013-10-24AC33157ND
2013-10-29AC33551ND
2013-10-29AC33554ND
2013-10-29AC33553ND
2013-10-29AC33552ND
2013-10-29AC33556ND
2013-10-29AC33557ND
2013-10-29AC33561ND
2013-10-29AC33555ND
2013-10-29AC33558ND
2013-11-04AC33928ND
2013-11-04AC33926ND
2013-11-04AC33930ND
2013-11-04AC33925ND
2013-11-04AC33929ND
2013-11-04AC339320.0400 ppm
2013-11-04AC33936ND
2013-11-04AC33927ND
2013-11-04AC33931ND
2013-12-17AC37729ND
2014-04-16AC50720ND
2014-08-14AC63582ND
2014-10-09AC69305ND
2014-10-09AC69306ND
2014-12-09AC74088ND
2014-12-09AC74086ND
2014-12-09AC74087ND
2014-12-18AC75397ND
2014-12-18AC75396ND
2015-03-04AC82759ND
2015-03-05AC82769ND
2015-03-24AC85778ND
2015-06-04AC94540ND
2015-06-04AC94539ND
2015-07-21AD00268ND
2015-07-21AD00267ND
2015-07-22AD00530ND
2015-07-22AD00533ND
2015-07-22AD00532ND
2015-07-22AD00531ND
2015-10-22AD11386ND
2015-10-22AD113810.01000 ppm
2015-10-22AD11385ND
2015-10-22AD11383ND
2015-10-22AD11382ND
2015-10-22AD11387ND
2015-10-22AD11384ND
2015-10-22AD11388ND
2015-11-12AD13270ND
2015-11-12AD13269ND
2015-11-12AD13268ND
2015-11-12AD13274ND
2015-11-12AD13271ND
2015-11-12AD13272ND
2015-11-12AD13273ND
2015-11-12AD13275ND
2015-12-08AD15859ND
2017-01-26AD66977ND