Nitrate
Barrow Subdivision
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 | 0.355 ppm | 5 | 5 | 0.252 ppm - 0.570 ppm |
| 2019 | 0.338 ppm | 5 | 5 | 0.0765 ppm - 0.471 ppm |
| 2020 | 0.397 ppm | 5 | 5 | 0.140 ppm - 0.699 ppm |
| 2021 | 0.491 ppm | 5 | 5 | 0.320 ppm - 0.666 ppm |
| 2022 | 0.523 ppm | 5 | 5 | 0.264 ppm - 1.15 ppm |
| 2023 | 0.322 ppm | 5 | 5 | 0.208 ppm - 0.455 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 |
|---|---|---|
| 2018-02-13 | Q1805809001 | 0.344 ppm |
| 2018-05-08 | Q1818541001 | 0.570 ppm |
| 2018-08-15 | Q1832665004 | 0.252 ppm |
| 2018-08-15 | Q1832665005 | 0.307 ppm |
| 2018-11-29 | Q1848702001 | 0.301 ppm |
| 2019-03-05 | Q1909225002 | 0.471 ppm |
| 2019-06-05 | Q1932128001 | 0.471 ppm |
| 2019-06-25 | Q1939682002 | 0.0765 ppm |
| 2019-09-23 | Q1967454001 | 0.241 ppm |
| 2019-12-12 | Q1979958001 | 0.432 ppm |
| 2020-02-19 | Q2006394005 | 0.699 ppm |
| 2020-02-19 | Q2006394006 | 0.604 ppm |
| 2020-05-21 | Q2020430001 | 0.140 ppm |
| 2020-09-21 | Q2037388001 | 0.204 ppm |
| 2020-12-15 | Q2049673001 | 0.336 ppm |
| 2021-02-23 | Q2104584006 | 0.666 ppm |
| 2021-02-23 | Q2104584009 | 0.373 ppm |
| 2021-06-10 | Q2115247001 | 0.624 ppm |
| 2021-09-15 | Q2125278001 | 0.320 ppm |
| 2021-11-04 | Q2131002001 | 0.473 ppm |
| 2022-02-25 | Q2206630001 | 0.302 ppm |
| 2022-05-11 | Q2214175001 | 0.520 ppm |
| 2022-08-23 | Q2224983001 | 0.264 ppm |
| 2022-12-07 | Q2236659001 | 1.15 ppm |
| 2022-12-07 | Q2236659002 | 0.377 ppm |
| 2023-02-16 | Q2306408001 | 0.358 ppm |
| 2023-05-17 | Q2318658005 | 0.237 ppm |
| 2023-05-17 | Q2318658006 | 0.208 ppm |
| 2023-09-19 | Q2340247001 | 0.351 ppm |
| 2023-11-16 | Q2349438001 | 0.455 ppm |