Know Your Environment. Protect Your Health.

Nitrate and nitrite

Aquarion Water Company of Connecticut - Main System

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.

 

48

Samples

0

Samples exceeding legal limit (MCL)

34

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.560 ppm880.0880 ppm - 1.29 ppm
20190.598 ppm880.167 ppm - 1.34 ppm
20200.557 ppm880.121 ppm - 1.28 ppm
20210.588 ppm880.0900 ppm - 1.33 ppm
20220.482 ppm85ND - 1.60 ppm
20230.503 ppm85ND - 1.56 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

ppm = parts per million

All test results

Date Lab ID Result
2018-02-05201801570-NOX0.337 ppm
2018-02-05201801586-NOX0.0930 ppm
2018-02-05201801587-IOCR0.0880 ppm
2018-02-05201801571-IOCR0.332 ppm
2018-02-05201801603-IOCR0.632 ppm
2018-02-05201801604-NOX0.599 ppm
2018-07-05201809662-NOX1.11 ppm
2018-07-05201809658-NOX1.29 ppm
2019-02-04201901553-IOCR0.550 ppm
2019-02-04201901582-IOCR0.396 ppm
2019-02-04201901614-IOCR0.177 ppm
2019-02-04201901613-NOX0.167 ppm
2019-02-04201901581-NOX0.378 ppm
2019-02-04201901554-NOX0.523 ppm
2019-07-01201909695-NOX1.26 ppm
2019-07-01201909693-NOX1.34 ppm
2020-02-03202001681-NOX0.600 ppm
2020-02-03202001624-NOX0.326 ppm
2020-02-03202001640-NOX0.123 ppm
2020-02-03202001641-IOCR0.121 ppm
2020-02-03202001625-IOCR0.304 ppm
2020-02-03202001680-IOCR0.589 ppm
2020-07-07202010259-NOX1.11 ppm
2020-07-07202010253-NOX1.28 ppm
2021-02-02202101448-NOX0.684 ppm
2021-02-02202101447-IOCR0.680 ppm
2021-02-02202101395-IOCR0.342 ppm
2021-02-02202101406-NOX0.111 ppm
2021-02-02202101394-NOX0.355 ppm
2021-02-02202101407-IOCR0.0900 ppm
2021-07-06202110289-NOX1.12 ppm
2021-07-06202110283-NOX1.33 ppm
2022-02-07202202089-IOCRND
2022-02-07202202023-IOCRND
2022-02-07202202034-IOCRND
2022-02-07202202033-NOX0.127 ppm
2022-02-07202202022-NOX0.287 ppm
2022-02-07202202090-NOX0.477 ppm
2022-07-05202210995-NOX1.37 ppm
2022-07-05202210989-NOX1.60 ppm
2023-02-06202301854-NOX0.565 ppm
2023-02-06202301775-NOX0.0690 ppm
2023-02-06202301771-IOCRND
2023-02-06202301853-IOCRND
2023-02-09202302139-NOX0.418 ppm
2023-02-09202302140-IOCRND
2023-06-07202309441-NOX1.42 ppm
2023-06-07202309440-NOX1.56 ppm