Nitrate and nitrite
Cobb County
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.
Samples
Samples exceeding legal limit (MCL)
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2013 | N/A | 0 | 0 | N/A |
| 2014 | 0.500 ppm | 2 | 2 | 0.280 ppm - 0.720 ppm |
| 2015 | 0.600 ppm | 2 | 1 | ND - 1.20 ppm |
| 2016 | 0.410 ppm | 2 | 2 | 0.280 ppm - 0.540 ppm |
| 2017 | 0.600 ppm | 1 | 1 | ND - 1.20 ppm |
| 2018 | 1.000 ppm | 1 | 1 | 0.300 ppm - 1.000 ppm |
| 2019 | 0.770 ppm | 1 | 1 | 0.330 ppm - 0.770 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 |
|---|---|---|
| 2017-06-01 | 0.600 ppm* | |
| 2018-06-01 | 1.000 ppm* | |
| 2019-06-01 | 0.770 ppm* |
* Sample result is taken from the system's CCR report.