Know Your Environment. Protect Your Health.

Nitrate and nitrite

Clarendon Waterworks

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.

 

8

Samples

0

Samples exceeding legal limit (MCL)

7

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.877 ppm330.710 ppm - 1.02 ppm
2019ND10ND
20200.860 ppm110.860 ppm
20211.29 ppm111.29 ppm
20220.990 ppm110.990 ppm
20231.01 ppm111.01 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
2018-04-24Y1811600381.02 ppm
2018-08-21Y1823500080.710 ppm
2018-09-11Y1825600010.900 ppm
2019-04-16Y191080011ND
2020-04-21Y2011400100.860 ppm
2021-08-09Y2122400201.29 ppm
2022-04-25Y2211800300.990 ppm
2023-04-10Y2310300121.01 ppm