Know Your Environment. Protect Your Health.

Nitrate and nitrite

Silverdale Water District 16

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)

3

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2018ND10ND
2019ND10ND
2020N/A00N/A
2021N/A00N/A
20220.455 ppm113ND - 1.98 ppm
2023N/A00N/A

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
2018-09-04ND
2019-11-25ND
2022-07-254419132ND
2022-09-124365910ND
2022-09-1243659031.32 ppm
2022-09-124365904ND
2022-09-124365909ND
2022-09-124365906ND
2022-09-124365908ND
2022-09-1243659021.98 ppm
2022-09-124365905ND
2022-09-124365907ND
2022-12-0844086951.71 ppm