Know Your Environment. Protect Your Health.

Nitrate

City of Oak Harbor

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.

 

15

Samples

0

Samples exceeding legal limit (MCL)

7

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.500 ppm330.120 ppm - 1.03 ppm
20190.380 ppm31ND - 1.14 ppm
2020N/A00N/A
20210.387 ppm31ND - 1.16 ppm
20220.403 ppm32ND - 1.01 ppm
20230.343 ppm31ND - 1.03 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

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
2018-03-191.03 ppm
2018-03-190.120 ppm
2018-08-090.350 ppm
2019-03-211.14 ppm
2019-03-21ND
2019-08-15ND
2021-06-294132306ND
2021-06-2941322891.16 ppm
2021-06-294132305ND
2022-06-0942889351.01 ppm
2022-06-0942889370.200 ppm
2022-06-094288934ND
2023-06-274468451ND
2023-06-274468452ND
2023-06-2744684531.03 ppm