Nitrate and nitrite

Wailuku

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	N/A	0	0	N/A
2015	N/A	0	0	N/A
2016	0.694 ppm	18	18	0.180 ppm - 2.99 ppm
2017	0.839 ppm	15	15	0.180 ppm - 3.05 ppm
2018	N/A	0	0	N/A
2019	N/A	0	0	N/A

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
2016-03-31		0.800 ppm
2016-03-31		0.220 ppm
2016-03-31		0.610 ppm
2016-03-31		0.260 ppm
2016-09-12		0.840 ppm
2016-09-12		0.840 ppm
2016-11-30		0.800 ppm
2016-11-30		0.460 ppm
2016-11-30		0.460 ppm
2016-11-30		0.800 ppm
2016-11-30		0.800 ppm
2016-11-30		2.99 ppm
2016-11-30		0.180 ppm
2016-12-14		0.650 ppm
2016-12-14		0.650 ppm
2016-12-15		0.360 ppm
2016-12-15		0.360 ppm
2016-12-15		0.410 ppm
2017-09-07		0.420 ppm
2017-09-07		0.260 ppm
2017-09-07		0.400 ppm
2017-09-07		0.420 ppm
2017-09-14		0.180 ppm
2017-09-14		0.720 ppm
2017-09-14		0.900 ppm
2017-09-14		3.05 ppm
2017-09-14		3.05 ppm
2017-09-14		0.870 ppm
2017-09-14		0.860 ppm
2017-09-14		0.260 ppm
2017-09-21		0.210 ppm
2017-09-21		0.210 ppm
2017-12-06		0.770 ppm