Menu

EWG's Tap Water Database — 2019 UPDATE

Donate

Nitrate and nitrite

City of Rockport

NOTE: City of Rockport purchases water from San Patricio Municipal Water District which is required to test for nitrate and nitrite. Sample information shown below was taken by San Patricio Municipal Water District.

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.

 

4

Samples

0

Samples exceeding legal limit (MCL)

3

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20120.455 ppm220.453 ppm - 0.456 ppm
20130.365 ppm220.340 ppm - 0.390 ppm
20140.125 ppm220.120 ppm - 0.130 ppm
20150.195 ppm220.190 ppm - 0.200 ppm
2016N/A00N/A
2017N/A00N/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

NOTE: City of Rockport purchases water from San Patricio Municipal Water District which is required to test for nitrate and nitrite. Sample information shown below was taken by San Patricio Municipal Water District.

Date Lab ID Result
2012-03-0712032820010.634 ppm
2013-06-13AC219600.230 ppm
2014-04-24AC516250.170 ppm
2015-09-10AD063930.140 ppm