Nitrate and nitrite
City of Columbus
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.
18
Samples
0
Samples exceeding legal limit (MCL)
11
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2014 | 0.273 ppm | 3 | 3 | 0.0824 ppm - 0.595 ppm |
| 2015 | 0.461 ppm | 3 | 3 | 0.0510 ppm - 1.24 ppm |
| 2016 | 0.392 ppm | 3 | 2 | ND - 0.864 ppm |
| 2017 | 0.329 ppm | 3 | 3 | 0.0614 ppm - 0.586 ppm |
| 2018 | 0.292 ppm | 3 | 3 | 0.0577 ppm - 0.600 ppm |
| 2019 | 0.248 ppm | 3 | 3 | 0.0689 ppm - 0.507 ppm |
ppm = parts per million
State and national drinking water standards and health guidelines
EWG Health Guideline 0.14 ppm
The 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 |
|---|---|---|
| 2014-02-05 | 279691 | 0.141 ppm |
| 2014-02-05 | 279690 | 0.0824 ppm |
| 2014-08-25 | 309104 | 0.595 ppm |
| 2015-02-03 | 344085 | 0.0510 ppm |
| 2015-02-03 | 344086 | 0.0931 ppm |
| 2015-08-12 | 373971 | 1.24 ppm |
| 2016-02-22 | ND | |
| 2016-02-22 | 0.311 ppm | |
| 2016-08-10 | 0.864 ppm | |
| 2017-01-31 | 0.340 ppm | |
| 2017-02-27 | 0.0614 ppm | |
| 2017-08-07 | 0.586 ppm | |
| 2018-02-06 | 531046 | 0.0577 ppm |
| 2018-02-06 | 531047 | 0.218 ppm |
| 2018-08-20 | 562454 | 0.600 ppm |
| 2019-02-11 | 591096 | 0.167 ppm |
| 2019-02-11 | 591097 | 0.0689 ppm |
| 2019-08-27 | 618324 | 0.507 ppm |