Nitrate and nitrite
New London Department of Public Utilities
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.
Testing results - average by year
Year | Average result | Samples taken | Detections | Range of results |
---|---|---|---|---|
2013 | N/A | 0 | 0 | N/A |
2014 | 0.0125 ppm | 2 | 2 | 0.00900 ppm - 0.0160 ppm |
2015 | N/A | 0 | 0 | N/A |
2016 | 0.00750 ppm | 2 | 2 | 0.00500 ppm - 0.01000 ppm |
2017 | 0.0170 ppm | 2 | 2 | 0.0110 ppm - 0.0230 ppm |
2018 | 0.0765 ppm | 2 | 2 | 0.0650 ppm - 0.0880 ppm |
2019 | 0.0235 ppm | 2 | 2 | 0.0230 ppm - 0.0240 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 |
---|---|---|
2014-10-23 | 19658IOCR | 0.00900 ppm |
2014-10-23 | 19663NOX | 0.0160 ppm |
2016-10-27 | 23837NOX | 0.01000 ppm |
2016-10-27 | 23840IOCR | 0.00500 ppm |
2017-10-26 | 26206NOX | 0.0230 ppm |
2017-10-26 | 26209IOCR | 0.0110 ppm |
2018-11-29 | 28422NOX | 0.0880 ppm |
2018-11-29 | 28425IOCR | 0.0650 ppm |
2019-11-20 | 30475NOX | 0.0240 ppm |
2019-11-20 | 30469IOCR | 0.0230 ppm |