Nitrate
PUD #1 of Asotin County
Nitrate, a fertilizer chemical, frequently contaminates drinking water due to agricultural and urban runoff, and discharges from municipal wastewater treatment plants and septic tanks. Excessive nitrate in water can cause oxygen deprivation in infants and increase the risk of cancer. 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 | 0.268 ppm | 6 | 3 | ND - 0.736 ppm |
| 2019 | 0.229 ppm | 6 | 3 | ND - 0.670 ppm |
| 2020 | N/A | 0 | 0 | N/A |
| 2021 | 0.176 ppm | 6 | 3 | ND - 0.628 ppm |
| 2022 | 0.462 ppm | 6 | 3 | ND - 1.70 ppm |
| 2023 | 0.493 ppm | 6 | 3 | ND - 1.82 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
The legal limit for nitrate, established in 1962, was developed to protect infants from acute methemoglobinemia, a life-threatening disorder of oxygen transport in the body. This limit does not fully protect against the risk of cancer and harm to the developing fetus.
ppm = parts per million
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2018-06-20 | ND | |
| 2018-06-20 | 0.736 ppm | |
| 2018-06-20 | ND | |
| 2018-06-20 | 0.725 ppm | |
| 2018-06-20 | ND | |
| 2018-06-20 | 0.144 ppm | |
| 2019-06-06 | 0.106 ppm | |
| 2019-06-06 | ND | |
| 2019-06-06 | 0.670 ppm | |
| 2019-06-06 | ND | |
| 2019-06-06 | 0.598 ppm | |
| 2019-06-06 | ND | |
| 2021-08-23 | 4167048 | ND |
| 2021-08-23 | 4167045 | 0.247 ppm |
| 2021-08-23 | 4167046 | ND |
| 2021-08-23 | 4167047 | 0.628 ppm |
| 2021-08-23 | 4167044 | ND |
| 2021-08-23 | 4167049 | 0.182 ppm |
| 2022-08-15 | 4334023 | 0.318 ppm |
| 2022-08-15 | 4334028 | 0.752 ppm |
| 2022-08-15 | 4334025 | ND |
| 2022-08-15 | 4334030 | ND |
| 2022-08-15 | 4334020 | ND |
| 2022-08-15 | 4334031 | 1.70 ppm |
| 2023-08-14 | 4504045 | ND |
| 2023-08-14 | 4504047 | ND |
| 2023-08-14 | 4504049 | ND |
| 2023-08-14 | 4504050 | 1.82 ppm |
| 2023-08-14 | 4504046 | 0.352 ppm |
| 2023-08-14 | 4504048 | 0.787 ppm |