Know Your Environment. Protect Your Health.

Nitrate and nitrite

Aquarion Water Company of Connecticut - Mystic

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)

5

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.0495 ppm220.0440 ppm - 0.0550 ppm
20190.235 ppm330.106 ppm - 0.463 ppm
20200.197 ppm330.0990 ppm - 0.380 ppm
20210.172 ppm330.0550 ppm - 0.392 ppm
20220.0695 ppm41ND - 0.278 ppm
20230.181 ppm32ND - 0.438 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
2018-05-07201806152-IOCR0.0440 ppm
2018-05-07201806155-NOX0.0550 ppm
2019-05-07201906220-NOX0.135 ppm
2019-05-07201906217-IOCR0.106 ppm
2019-10-28201917770-NOX0.463 ppm
2020-05-04202006226-NOX0.111 ppm
2020-05-04202006223-IOCR0.0990 ppm
2020-10-19202017023-NOX0.380 ppm
2021-05-03202106135-NOX0.392 ppm
2021-05-03202106126-IOCR0.0550 ppm
2021-05-03202106129-NOX0.0690 ppm
2022-05-02202206699-NOXND
2022-07-18202212124-IOCRND
2022-07-18202212124-NOXND
2022-08-29202215061-NOX0.278 ppm
2023-05-01202306890-NOX0.106 ppm
2023-05-01202306887-IOCRND
2023-06-20202310453-NOX0.438 ppm