Nitrate and nitrite

Ozark Mtn Regional PWA

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.

MORE ABOUT THIS CONTAMINANT

Samples

Samples exceeding legal limit (MCL)

Samples exceeding
health guidelines

Testing results - average by year

Year	Average result	Samples taken	Detections	Range of results
2014	0.250 ppm	4	3	ND - 0.470 ppm
2015	0.305 ppm	4	3	ND - 0.500 ppm
2016	0.320 ppm	4	4	0.120 ppm - 0.590 ppm
2017	0.340 ppm	4	4	0.190 ppm - 0.530 ppm
2018	0.213 ppm	4	3	ND - 0.390 ppm
2019	0.388 ppm	5	4	ND - 0.560 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
2014-01-21	140230004	0.470 ppm
2014-04-30	141210007	0.410 ppm
2014-08-18	142330012	0.120 ppm
2014-10-27	Y143030009	ND
2015-01-27	Y150290022	0.320 ppm
2015-04-27	Y151200026	0.400 ppm
2015-07-27	Y152100011	0.500 ppm
2015-10-28	Y153020012	ND
2016-03-01	Y160630020	0.590 ppm
2016-05-16	Y161400010	0.440 ppm
2016-08-22	Y162390003	0.120 ppm
2016-11-14	Y163210039	0.130 ppm
2017-02-07	Y170400015	0.300 ppm
2017-04-24	Y171180013	0.340 ppm
2017-07-24	Y172080015	0.530 ppm
2017-10-23	Y172990006	0.190 ppm
2018-01-24	Y180250031	0.280 ppm
2018-05-07	Y181300002	0.390 ppm
2018-07-30	Y182130115	ND
2018-10-23	Y182980008	0.180 ppm
2019-01-28	Y190310026	0.560 ppm
2019-03-26	Y190860024	0.550 ppm
2019-04-29	Y191220028	0.390 ppm
2019-08-20	Y192340011	0.440 ppm
2019-10-29	Y193050003	ND