Know Your Environment. Protect Your Health.

Nitrate and nitrite

Tualatin Valley Water District

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.

 

13

Samples

0

Samples exceeding legal limit (MCL)

9

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.458 ppm330.280 ppm - 0.591 ppm
20190.521 ppm110.521 ppm
20200.326 ppm64ND - 0.561 ppm
2021ND10ND
2022ND10ND
20230.610 ppm110.610 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
2018-06-18816903001-I0.591 ppm
2018-09-17826001901-I0.280 ppm
2018-11-07831111301-I0.503 ppm
2019-10-01927402701-I0.521 ppm
2020-01-21002104103-I0.529 ppm
2020-02-25005603501-I0.561 ppm
2020-04-17010801201-IND
2020-08-26023903501-I0.470 ppm
2020-09-23026703501-IND
2020-11-04030901101-I0.398 ppm
2021-05-13113302201-IND
2022-07-252206015-01-IND
2023-09-2623-587130.610 ppm