Know Your Environment. Protect Your Health.

Nitrate and nitrite

Johnston County Rural Water District #3

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)

18

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20181.07 ppm330.340 ppm - 1.61 ppm
20190.800 ppm330.260 ppm - 1.23 ppm
20200.857 ppm330.290 ppm - 1.26 ppm
20211.05 ppm330.260 ppm - 1.60 ppm
20220.967 ppm330.330 ppm - 1.39 ppm
20232.82 ppm330.430 ppm - 5.12 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
2018-06-19SDWA-1270322-001.61 ppm
2018-06-19SDWA-1270324-001.25 ppm
2018-06-19SDWA-1270320-000.340 ppm
2019-05-06SDWA-1372780-000.260 ppm
2019-05-06SDWA-1372782-001.23 ppm
2019-05-06SDWA-1372784-000.910 ppm
2020-08-31SDWA-1506327-000.290 ppm
2020-08-31SDWA-1506329-001.26 ppm
2020-08-31SDWA-1506331-001.02 ppm
2021-06-01SDWA-1568298-000.260 ppm
2021-06-01SDWA-1568302-001.60 ppm
2021-06-01SDWA-1568300-001.30 ppm
2022-05-04SDWA-1693790-000.330 ppm
2022-05-04SDWA-1693792-001.18 ppm
2022-05-04SDWA-1693794-001.39 ppm
2023-07-19SDWA-1810316-000.430 ppm
2023-07-19SDWA-1810324-002.91 ppm
2023-07-19SDWA-1810325-005.12 ppm