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EWG's Tap Water Database — 2021 UPDATE

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Nitrate and nitrite

Denver Water Board

Nitrate and nitrite enter water from fertilizer runoff, septic tanks and urban runoff. These contaminants can cause oxygen deprivation for infants and increase the risk of cancer. Nitrite is significantly more toxic than nitrate. Click here to read more about nitrate.

 

26

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
20140.0700 ppm880.0400 ppm - 0.1000 ppm
20150.0700 ppm220.0500 ppm - 0.0900 ppm
2016N/A00N/A
2017N/A00N/A
2018N/A00N/A
20190.0381 ppm166ND - 0.130 ppm

ppm = parts per million

State and national drinking water standards and health guidelines

EWG Health Guideline 0.14 ppm

The health guideline of 0.14 parts per million, or ppm, for nitrate and nitrite is based on the equivalent health guideline for nitrate, as defined in a peer-reviewed scientific study by EWG. This guideline represents a one-in-one-million annual cancer risk level.

EPA Maximum Contaminant
Level (MCL) 10 ppm

ppm = parts per million

All test results

Date Result
2014-05-270.1000 ppm
2014-05-270.0500 ppm
2014-05-270.0400 ppm
2014-08-180.0700 ppm
2014-08-180.0900 ppm
2014-08-180.0600 ppm
2014-11-200.0900 ppm
2014-11-200.0600 ppm
2015-02-180.0900 ppm
2015-02-180.0500 ppm
2019-07-02ND
2019-07-020.0800 ppm
2019-07-020.0600 ppm
2019-08-06ND
2019-08-06ND
2019-08-06ND
2019-09-100.120 ppm
2019-09-100.130 ppm
2019-09-10ND
2019-10-080.110 ppm
2019-10-08ND
2019-10-08ND
2019-11-05ND
2019-11-050.110 ppm
2019-12-03ND
2019-12-03ND