Nitrate and nitrite
Sharon Water & Sewer Commission
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 | 0.163 ppm | 3 | 3 | 0.0700 ppm - 0.250 ppm |
| 2019 | 0.170 ppm | 3 | 3 | 0.120 ppm - 0.220 ppm |
| 2020 | 0.113 ppm | 3 | 3 | 0.0900 ppm - 0.160 ppm |
| 2021 | 0.0867 ppm | 3 | 3 | 0.0700 ppm - 0.1000 ppm |
| 2022 | 0.143 ppm | 3 | 3 | 0.1000 ppm - 0.230 ppm |
| 2023 | 0.0933 ppm | 3 | 3 | 0.0600 ppm - 0.130 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 |
|---|---|---|
| 2018-12-20 | CC18174 | 0.0700 ppm |
| 2018-12-20 | CC18175 | 0.170 ppm |
| 2018-12-20 | CC18173 | 0.250 ppm |
| 2019-12-18 | CE90115 | 0.170 ppm |
| 2019-12-18 | CE90117 | 0.120 ppm |
| 2019-12-18 | CE90116 | 0.220 ppm |
| 2020-12-16 | CH33643 | 0.0900 ppm |
| 2020-12-16 | CH33645 | 0.160 ppm |
| 2020-12-16 | CH33644 | 0.0900 ppm |
| 2021-12-15 | CJ99309 | 0.0900 ppm |
| 2021-12-15 | CJ99310 | 0.1000 ppm |
| 2021-12-15 | CJ99311 | 0.0700 ppm |
| 2022-12-07 | CM99871 | 0.1000 ppm |
| 2022-12-07 | CM99873 | 0.230 ppm |
| 2022-12-07 | CM99872 | 0.1000 ppm |
| 2023-12-06 | CP61721 | 0.0600 ppm |
| 2023-12-06 | CP61723 | 0.130 ppm |
| 2023-12-06 | CP61722 | 0.0900 ppm |