Nitrate and nitrite

Parker WSD

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

104

Samples

Samples exceeding legal limit (MCL)

Samples exceeding
health guidelines

Testing results - average by year

Year	Average result	Samples taken	Detections	Range of results
2013	N/A	0	0	N/A
2014	0.132 ppm	20	9	ND - 0.662 ppm
2015	0.0785 ppm	19	13	ND - 0.553 ppm
2016	0.0374 ppm	20	6	ND - 0.200 ppm
2017	0.188 ppm	28	23	ND - 0.895 ppm
2018	0.0777 ppm	9	4	ND - 0.277 ppm
2019	0.0305 ppm	8	1	ND - 0.244 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	Result
2014-01-17	ND
2014-01-17	0.439 ppm
2014-01-17	ND
2014-01-17	ND
2014-04-30	ND
2014-05-07	0.0980 ppm
2014-05-08	ND
2014-05-20	ND
2014-06-12	ND
2014-06-16	0.200 ppm
2014-06-19	0.400 ppm
2014-07-02	ND
2014-07-17	ND
2014-07-24	0.182 ppm
2014-07-24	ND
2014-07-31	ND
2014-07-31	0.662 ppm
2014-07-31	0.199 ppm
2014-07-31	0.400 ppm
2014-08-21	0.0660 ppm
2015-02-04	0.163 ppm
2015-04-17	0.0570 ppm
2015-04-17	0.1000 ppm
2015-04-27	ND
2015-05-18	ND
2015-05-21	ND
2015-05-27	0.0630 ppm
2015-06-10	0.0510 ppm
2015-06-10	0.0520 ppm
2015-06-16	0.0630 ppm
2015-06-17	0.0610 ppm
2015-06-24	ND
2015-06-25	ND
2015-08-13	0.0510 ppm
2015-08-26	0.0840 ppm
2015-09-10	0.113 ppm
2015-09-24	0.0810 ppm
2015-10-13	0.553 ppm
2015-10-21	ND
2016-01-28	0.200 ppm
2016-01-28	0.197 ppm
2016-03-03	0.0520 ppm
2016-03-10	0.0660 ppm
2016-05-03	0.135 ppm
2016-06-06	ND
2016-06-06	ND
2016-06-06	ND
2016-06-06	ND
2016-07-14	ND
2016-07-14	ND
2016-07-14	ND
2016-07-14	ND
2016-07-18	ND
2016-07-27	ND
2016-07-27	ND
2016-07-27	0.0970 ppm
2016-07-28	ND
2016-08-03	ND
2016-10-04	ND
2017-03-29	0.187 ppm
2017-03-29	0.271 ppm
2017-03-29	0.189 ppm
2017-03-29	0.209 ppm
2017-04-20	0.200 ppm
2017-04-20	ND
2017-04-25	0.185 ppm
2017-04-26	0.214 ppm
2017-04-26	0.192 ppm
2017-04-26	0.190 ppm
2017-05-22	0.195 ppm
2017-05-22	0.220 ppm
2017-05-22	0.296 ppm
2017-05-22	0.190 ppm
2017-05-22	0.202 ppm
2017-05-22	0.192 ppm
2017-05-22	0.192 ppm
2017-05-26	ND
2017-05-26	ND
2017-06-08	0.152 ppm
2017-06-12	0.185 ppm
2017-06-12	0.148 ppm
2017-06-12	0.151 ppm
2017-06-12	0.162 ppm
2017-07-07	0.895 ppm
2017-07-07	0.252 ppm
2017-07-18	ND
2017-08-30	ND
2018-05-09	ND
2018-06-25	0.277 ppm
2018-07-17	ND
2018-07-23	ND
2018-07-23	ND
2018-07-23	0.134 ppm
2018-08-01	0.0960 ppm
2018-08-16	ND
2018-08-16	0.192 ppm
2019-04-16	ND
2019-04-16	ND
2019-04-17	ND
2019-04-22	0.244 ppm
2019-04-23	ND
2019-04-24	ND
2019-04-25	ND
2019-04-25	ND