Nitrate
Starr Water Supply Corporation
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 | 0.0447 ppm | 4 | 4 | 0.0290 ppm - 0.0614 ppm |
| 2019 | 0.0537 ppm | 4 | 4 | 0.0407 ppm - 0.0620 ppm |
| 2020 | 0.0480 ppm | 4 | 4 | 0.0352 ppm - 0.0606 ppm |
| 2021 | 0.0432 ppm | 4 | 4 | 0.0340 ppm - 0.0508 ppm |
| 2022 | 0.0562 ppm | 4 | 4 | 0.0349 ppm - 0.0834 ppm |
| 2023 | 0.0447 ppm | 4 | 4 | 0.0374 ppm - 0.0513 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 |
|---|---|---|
| 2018-10-04 | Q1839859014 | 0.0524 ppm |
| 2018-10-04 | Q1839859015 | 0.0359 ppm |
| 2018-10-04 | Q1839859016 | 0.0290 ppm |
| 2018-10-04 | Q1839859013 | 0.0614 ppm |
| 2019-08-27 | Q1960470010 | 0.0407 ppm |
| 2019-08-27 | Q1960470011 | 0.0599 ppm |
| 2019-08-27 | Q1960470012 | 0.0520 ppm |
| 2019-12-11 | Q1979772004 | 0.0620 ppm |
| 2020-09-29 | Q2038300018 | 0.0467 ppm |
| 2020-09-29 | Q2038300019 | 0.0493 ppm |
| 2020-09-29 | Q2038300020 | 0.0352 ppm |
| 2020-12-28 | Q2050292001 | 0.0606 ppm |
| 2021-05-19 | Q2113143001 | 0.0473 ppm |
| 2021-11-17 | Q2132246003 | 0.0407 ppm |
| 2021-11-17 | Q2132246004 | 0.0508 ppm |
| 2021-11-17 | Q2132246005 | 0.0340 ppm |
| 2022-10-19 | Q2231830001 | 0.0571 ppm |
| 2022-10-19 | Q2231830014 | 0.0495 ppm |
| 2022-10-19 | Q2231830015 | 0.0834 ppm |
| 2022-10-19 | Q2231830016 | 0.0349 ppm |
| 2023-06-26 | Q2324322013 | 0.0454 ppm |
| 2023-06-26 | Q2324322014 | 0.0448 ppm |
| 2023-06-26 | Q2324322015 | 0.0374 ppm |
| 2023-06-26 | Q2324322032 | 0.0513 ppm |