Know Your Environment. Protect Your Health.

Nitrate and nitrite

Manchester 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.

 

48

Samples

0

Samples exceeding legal limit (MCL)

45

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20181.69 ppm880.240 ppm - 3.48 ppm
20191.87 ppm880.290 ppm - 3.33 ppm
20201.91 ppm880.111 ppm - 4.13 ppm
20211.67 ppm880.224 ppm - 3.36 ppm
20221.58 ppm880.120 ppm - 3.53 ppm
20231.63 ppm880.210 ppm - 3.50 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
2018-01-08AA82328-NOX0.900 ppm
2018-01-08AA82329-NOX1.92 ppm
2018-01-08AA82323-NOX0.240 ppm
2018-01-09AA82347-NOX3.48 ppm
2018-01-09AA82348-NOX2.71 ppm
2018-01-10AA82372-NOX2.60 ppm
2018-01-10AA82373-NOX1.41 ppm
2018-02-23AA82899-IOCR0.290 ppm
2019-05-16AA88408-IOCR0.353 ppm
2019-12-02AA90921-NOX0.290 ppm
2019-12-02AA90923-NOX1.08 ppm
2019-12-02AA90924-NOX2.99 ppm
2019-12-03AA90942-NOX2.81 ppm
2019-12-03AA90941-NOX3.33 ppm
2019-12-04AA90959-NOX2.62 ppm
2019-12-04AA90960-NOX1.48 ppm
2020-10-01AA94988-IOCR0.111 ppm
2020-10-26AA95341-NOX0.200 ppm
2020-10-26AA95348-NOX1.48 ppm
2020-10-26AA95349-NOX2.44 ppm
2020-10-27AA95364-NOX4.13 ppm
2020-10-27AA95365-NOX2.81 ppm
2020-10-28AA95382-NOX2.62 ppm
2020-10-28AA95383-NOX1.52 ppm
2021-10-04211004-1-06NOX0.224 ppm
2021-10-04211004-3-02 NOX1.93 ppm
2021-10-04211004-3-01NOX1.000 ppm
2021-10-05211005-3-03 NOX3.36 ppm
2021-10-05211005-3-04 NOX2.53 ppm
2021-10-06211006-3-05 NOX2.72 ppm
2021-10-06211006-3-06 NOX1.33 ppm
2021-11-04211104-1-04RAW IOC0.266 ppm
2022-05-13220513-1-04 RAW IOC0.130 ppm
2022-11-14221114-1-06NOX0.120 ppm
2022-11-14221114-3-01NOX0.750 ppm
2022-11-14221114-3-02NOX2.21 ppm
2022-11-15221115-3-04NOX2.26 ppm
2022-11-15221115-3-03NOX3.53 ppm
2022-11-16221116-3-05NOX2.27 ppm
2022-11-16221116-3-06NOX1.34 ppm
2023-11-13231113-1-06NOX0.210 ppm
2023-11-13231113-3-01NOX1.01 ppm
2023-11-13231113-3-02NOX1.78 ppm
2023-11-14231114-3-03NOX3.50 ppm
2023-11-14231114-3-04NOX2.35 ppm
2023-11-15231115-3-05 NOX2.51 ppm
2023-11-15231115-3-06 NOX1.37 ppm
2023-12-05231205-1-04 RAW IOC0.300 ppm