Know Your Environment. Protect Your Health.

Nitrate and nitrite

Danbury Water Department

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.

 

30

Samples

0

Samples exceeding legal limit (MCL)

12

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.349 ppm440.0870 ppm - 0.640 ppm
20190.120 ppm660.0300 ppm - 0.230 ppm
20200.198 ppm440.0220 ppm - 0.327 ppm
20210.0650 ppm64ND - 0.185 ppm
20220.125 ppm42ND - 0.300 ppm
20230.0333 ppm61ND - 0.200 ppm

ppm = parts per million

State, National, and Health Guidelines for Drinking Water

EWG Health Guideline: 0.14 ppm

The EWG 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 Lab ID Result
2018-04-12212690GE0.580 ppm
2018-04-12212687GE0.640 ppm
2018-07-12NOX 2004994270.0870 ppm
2018-07-12NOX 2004994260.0870 ppm
2019-04-11NOX 2005281820.0490 ppm
2019-04-11NOX 2005281810.181 ppm
2019-04-11NOX 2005281850.173 ppm
2019-04-11NOX 2005281870.0300 ppm
2019-11-21NOX 2005577730.0590 ppm
2019-11-21NOX 2005577680.230 ppm
2020-02-20NOX 2005668930.327 ppm
2020-02-20NOX 2005668920.235 ppm
2020-08-20IOCR 2005873270.0220 ppm
2020-08-20IOCR 2005873290.206 ppm
2021-04-15IOCR 2006132960.115 ppm
2021-04-15IOCR 2006132940.185 ppm
2021-07-202694160.0400 ppm
2021-07-202694170.0500 ppm
2021-12-16278015ND
2021-12-16278014ND
2022-06-072873230.300 ppm
2022-06-072873270.200 ppm
2022-12-15303055ND
2022-12-15303056ND
2023-01-12304532ND
2023-01-12304533ND
2023-05-15N3E0590-02PPSND
2023-05-15N3E0590-01PPSND
2023-11-09CP44983ND
2023-11-09CP449820.200 ppm