Nitrate and nitrite
University of Connecticut - Main Campus
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.
Samples
Samples exceeding legal limit (MCL)
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2018 | 0.492 ppm | 2 | 2 | 0.0850 ppm - 0.899 ppm |
| 2019 | 0.471 ppm | 2 | 2 | 0.0810 ppm - 0.861 ppm |
| 2020 | 0.519 ppm | 2 | 2 | 0.0980 ppm - 0.940 ppm |
| 2021 | 0.454 ppm | 2 | 2 | 0.159 ppm - 0.748 ppm |
| 2022 | 0.355 ppm | 2 | 2 | 0.0900 ppm - 0.620 ppm |
| 2023 | 0.470 ppm | 2 | 2 | 0.0800 ppm - 0.860 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 |
|---|---|---|
| 2018-12-12 | NOX 200515892 | 0.0850 ppm |
| 2018-12-12 | NOX 200515895 | 0.899 ppm |
| 2019-11-19 | NOX 200557259 | 0.0810 ppm |
| 2019-11-19 | NOX 200557253 | 0.861 ppm |
| 2020-04-20 | NOX 200572965 | 0.0980 ppm |
| 2020-04-20 | NOX 200572966 | 0.940 ppm |
| 2021-09-14 | 300059939 300059940 | 0.159 ppm |
| 2021-09-14 | 300059942 300059943 | 0.748 ppm |
| 2022-12-06 | CM98053 | 0.0900 ppm |
| 2022-12-06 | CM98054 | 0.620 ppm |
| 2023-05-11 | CO03465 | 0.0800 ppm |
| 2023-05-11 | CO03466 | 0.860 ppm |