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EWG's Tap Water Database — 2021 UPDATE

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Nitrate

Howard Waterworks

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.

 

10

Samples

0

Samples exceeding legal limit (MCL)

4

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2014N/A00N/A
20150.120 ppm21ND - 0.240 ppm
20160.155 ppm21ND - 0.310 ppm
20170.220 ppm21ND - 0.440 ppm
2018ND20ND
20190.190 ppm21ND - 0.380 ppm

ppm = parts per million

State and national drinking water standards and health guidelines

EWG Health Guideline 0.14 ppm

The EWG Health Guideline of 0.14 ppm for nitrate was defined by EWG . This health guideline protects against cancer and harm to fetal growth and development.

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
2015-05-2745013953ND
2015-05-27450139520.240 ppm
2016-07-26460191890.310 ppm
2016-08-2946021846ND
2017-02-1447005442ND
2017-02-22470060490.440 ppm
2018-05-0948013086ND
2018-06-2148017547ND
2019-02-14490061550.380 ppm
2019-02-1949006490ND