Know Your Environment. Protect Your Health.

Nitrate

Washington State University

Nitrate, a fertilizer chemical, frequently contaminates drinking water due to agricultural and urban runoff, and discharges from municipal wastewater treatment plants and septic tanks. Excessive nitrate in water can cause oxygen deprivation in infants and increase the risk of cancer. Click here to read more about nitrate.

 

20

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2018ND40ND
2019ND50ND
2020N/A00N/A
2021ND40ND
2022ND40ND
2023ND30ND

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

The legal limit for nitrate, established in 1962, was developed to protect infants from acute methemoglobinemia, a life-threatening disorder of oxygen transport in the body. This limit does not fully protect against the risk of cancer and harm to the developing fetus.

ppm = parts per million

All test results

Date Lab ID Result
2018-07-18ND
2018-07-18ND
2018-08-16ND
2018-08-16ND
2019-07-23ND
2019-07-23ND
2019-07-23ND
2019-07-23ND
2019-07-23ND
2021-03-304092644ND
2021-03-304092645ND
2021-04-144106045ND
2021-04-144103054ND
2022-03-304263711ND
2022-03-304263710ND
2022-03-314263712ND
2022-05-314287778ND
2023-06-064473340ND
2023-06-064473339ND
2023-06-064473341ND