Nitrate
Appleby 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 | 0.0330 ppm | 7 | 7 | 0.0205 ppm - 0.0445 ppm |
| 2019 | 0.0350 ppm | 6 | 5 | ND - 0.0665 ppm |
| 2020 | 0.0401 ppm | 6 | 6 | 0.0211 ppm - 0.0625 ppm |
| 2021 | 0.0382 ppm | 7 | 7 | 0.0200 ppm - 0.0609 ppm |
| 2022 | 0.0416 ppm | 8 | 8 | 0.0193 ppm - 0.0610 ppm |
| 2023 | 0.0370 ppm | 8 | 7 | ND - 0.0802 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 |
|---|---|---|
| 2018-01-30 | Q1803539009 | 0.0445 ppm |
| 2018-04-18 | Q1815998009 | 0.0286 ppm |
| 2018-04-18 | Q1815998033 | 0.0336 ppm |
| 2018-04-18 | Q1815998032 | 0.0205 ppm |
| 2018-04-18 | Q1815998012 | 0.0328 ppm |
| 2018-04-18 | Q1815998011 | 0.0356 ppm |
| 2018-04-18 | Q1815998030 | 0.0356 ppm |
| 2019-01-24 | Q1903594001 | 0.0665 ppm |
| 2019-01-24 | Q1903594002 | ND |
| 2019-01-24 | Q1903594015 | 0.0307 ppm |
| 2019-01-24 | Q1903594016 | 0.0418 ppm |
| 2019-01-24 | Q1903594017 | 0.0463 ppm |
| 2019-04-24 | Q1916506001 | 0.0246 ppm |
| 2020-05-06 | Q2017875029 | 0.0211 ppm |
| 2020-05-06 | Q2017875048 | 0.0256 ppm |
| 2020-05-06 | Q2017875033 | 0.0569 ppm |
| 2020-05-06 | Q2017875032 | 0.0389 ppm |
| 2020-05-06 | Q2017875031 | 0.0357 ppm |
| 2020-05-06 | Q2017875030 | 0.0625 ppm |
| 2021-02-01 | Q2102897031 | 0.0200 ppm |
| 2021-02-01 | Q2102897030 | 0.0494 ppm |
| 2021-02-01 | Q2102897028 | 0.0609 ppm |
| 2021-02-01 | Q2102897025 | 0.0489 ppm |
| 2021-02-01 | Q2102897022 | 0.0288 ppm |
| 2021-02-01 | Q2102897029 | 0.0325 ppm |
| 2021-07-26 | Q2119473010 | 0.0266 ppm |
| 2022-02-01 | Q2203639010 | 0.0276 ppm |
| 2022-02-01 | Q2203639011 | 0.0299 ppm |
| 2022-02-01 | Q2203639015 | 0.0193 ppm |
| 2022-05-16 | Q2214437010 | 0.0378 ppm |
| 2022-09-06 | Q2226362015 | 0.0601 ppm |
| 2022-09-06 | Q2226362016 | 0.0610 ppm |
| 2022-09-06 | Q2226362014 | 0.0584 ppm |
| 2022-09-06 | Q2226362004 | 0.0383 ppm |
| 2023-03-07 | Q2308836008 | 0.0354 ppm |
| 2023-03-22 | Q2310842001 | 0.0192 ppm |
| 2023-03-22 | Q2310842003 | 0.0802 ppm |
| 2023-03-22 | Q2310842020 | ND |
| 2023-08-14 | Q2333697005 | 0.0318 ppm |
| 2023-08-14 | Q2333697006 | 0.0398 ppm |
| 2023-10-23 | Q2345174005 | 0.0598 ppm |
| 2023-10-23 | Q2345174016 | 0.0299 ppm |