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EWG's Tap Water Database — 2021 UPDATE

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Nitrate

Westby 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.

 

12

Samples

0

Samples exceeding legal limit (MCL)

6

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20140.527 ppm220.0540 ppm - 1.000 ppm
20150.516 ppm220.0560 ppm - 0.975 ppm
20160.488 ppm220.0460 ppm - 0.930 ppm
20170.639 ppm220.0580 ppm - 1.22 ppm
20180.500 ppm220.0610 ppm - 0.938 ppm
20190.535 ppm220.0590 ppm - 1.01 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
2014-09-174090670-020.0540 ppm
2014-10-094100368-011.000 ppm
2015-09-155090534-020.0560 ppm
2015-09-155090534-030.975 ppm
2016-09-206090735-020.0460 ppm
2016-09-206090735-010.930 ppm
2017-08-1417H0580-011.22 ppm
2017-09-1217I0333-010.0580 ppm
2018-09-2518I0804-020.0610 ppm
2018-09-2518I0804-010.938 ppm
2019-04-0219D0074-020.0590 ppm
2019-04-0219D0074-011.01 ppm