Know Your Environment. Protect Your Health.

Nitrate and nitrite

Kent Water Department

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.

 

45

Samples

0

Samples exceeding legal limit (MCL)

32

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.547 ppm116ND - 1.60 ppm
20190.696 ppm109ND - 1.20 ppm
2020N/A00N/A
20210.717 ppm98ND - 1.30 ppm
20220.709 ppm85ND - 1.60 ppm
20230.656 ppm74ND - 1.90 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
2018-07-16ND
2018-07-160.640 ppm
2018-07-16ND
2018-07-161.60 ppm
2018-07-16ND
2018-07-16ND
2018-07-16ND
2018-07-160.580 ppm
2018-07-171.20 ppm
2018-08-071.000 ppm
2018-08-071.000 ppm
2019-07-020.680 ppm
2019-07-021.20 ppm
2019-07-020.700 ppm
2019-07-120.620 ppm
2019-07-120.620 ppm
2019-07-160.670 ppm
2019-07-160.670 ppm
2019-07-220.900 ppm
2019-07-220.900 ppm
2019-07-23ND
2021-06-2341808000.910 ppm
2021-06-2341808000.910 ppm
2021-07-1342128891.30 ppm
2021-07-1342128880.750 ppm
2021-07-1342128900.660 ppm
2021-07-1342128900.660 ppm
2021-07-2042001530.630 ppm
2021-07-2042001530.630 ppm
2021-07-274203566ND
2022-06-2143005251.60 ppm
2022-07-1943208480.600 ppm
2022-07-2643264721.40 ppm
2022-07-264326474ND
2022-07-2643294051.40 ppm
2022-07-264326473ND
2022-07-2643294120.670 ppm
2022-07-264329409ND
2023-07-314506151ND
2023-07-3145061521.90 ppm
2023-07-314506150ND
2023-07-314511171ND
2023-07-3145111720.800 ppm
2023-07-3145111731.20 ppm
2023-07-3145111700.690 ppm