Know Your Environment. Protect Your Health.

Nitrate and nitrite

Patterson Water 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.

 

14

Samples

0

Samples exceeding legal limit (MCL)

4

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.810 ppm220.810 ppm
20190.0427 ppm660.0250 ppm - 0.0740 ppm
20200.0980 ppm330.0340 ppm - 0.200 ppm
2021ND10ND
20220.300 ppm110.300 ppm
2023ND10ND

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
2018-01-25353704150020.810 ppm
2018-01-25353704150020.810 ppm
2019-01-15354426740010.0740 ppm
2019-01-15354426740010.0740 ppm
2019-07-24354848560010.0290 ppm
2019-07-24354848560010.0290 ppm
2019-10-22355073440010.0250 ppm
2019-10-22355073440010.0250 ppm
2020-01-07355225720010.0600 ppm
2020-01-07355225720020.0340 ppm
2020-04-14B2001727-0010.200 ppm
2021-03-25B2101306-001ND
2022-01-06B2200050-0010.300 ppm
2023-01-30B2300412-001ND