EWG's Tap Water Database — 2019 UPDATE


Nitrate and nitrite

City of Lancaster

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.





Samples exceeding legal limit (MCL)


Samples exceeding
health guidelines

Testing results - average by year

YearAverage resultSamples takenDetectionsRange of results
20120.686 ppm220.411 ppm - 0.960 ppm
20140.527 ppm220.333 ppm - 0.720 ppm
20150.613 ppm220.470 ppm - 0.755 ppm

ppm = parts per million

State and national drinking water standards and health guidelines

EWG Health Guideline 0.14 ppm

The 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
2012-02-2112025870010.411 ppm
2012-02-2112025870020.960 ppm
2014-07-10Q14271720010.720 ppm
2014-07-10Q14271720020.333 ppm
2015-03-19Q15104650010.470 ppm
2015-08-18Q15326140010.755 ppm