Nitrate
City of Friendswood
Nitrate, a fertilizer chemical, frequently contaminates drinking water due to agricultural and urban runoff, and discharges from municipal wastewater treatment plants and septic tanks. Excessive nitrate in water can cause oxygen deprivation in infants and increase the risk of cancer. Click here to read more about nitrate.
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 | 0.412 ppm | 6 | 6 | 0.0400 ppm - 0.640 ppm |
| 2015 | 0.385 ppm | 6 | 6 | 0.0300 ppm - 0.590 ppm |
| 2016 | 0.255 ppm | 6 | 6 | 0.0200 ppm - 0.640 ppm |
| 2017 | 0.353 ppm | 6 | 6 | 0.0400 ppm - 0.690 ppm |
| 2018 | 0.257 ppm | 6 | 5 | ND - 0.610 ppm |
| 2019 | 0.257 ppm | 6 | 3 | ND - 0.530 ppm |
ppm = parts per million
State and national drinking water standards and health guidelines
EWG Health Guideline 0.14 ppm
The EWG Health Guideline of 0.14 ppm for nitrate was defined by EWG . This health guideline protects against cancer and harm to fetal growth and development.
EPA Maximum Contaminant
Level (MCL) 10 ppm
The legal limit for nitrate, established in 1962, was developed to protect infants from acute methemoglobinemia, a life-threatening disorder of oxygen transport in the body. This limit does not fully protect against the risk of cancer and harm to the developing fetus.
ppm = parts per million
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2014-02-20 | AC43753 | 0.640 ppm |
| 2014-02-20 | AC43754 | 0.630 ppm |
| 2014-06-02 | AC55535 | 0.0400 ppm |
| 2014-06-02 | AC55530 | 0.540 ppm |
| 2014-06-02 | AC55540 | 0.580 ppm |
| 2014-06-02 | AC55539 | 0.0400 ppm |
| 2015-02-05 | AC79366 | 0.0300 ppm |
| 2015-02-05 | AC79367 | 0.0300 ppm |
| 2015-02-05 | AC79368 | 0.590 ppm |
| 2015-02-05 | AC79365 | 0.570 ppm |
| 2015-02-05 | AC79363 | 0.590 ppm |
| 2015-02-05 | AC79386 | 0.500 ppm |
| 2016-02-04 | AD21994 | 0.610 ppm |
| 2016-02-04 | AD21989 | 0.640 ppm |
| 2016-02-04 | AD21991 | 0.0600 ppm |
| 2016-02-04 | AD21993 | 0.0200 ppm |
| 2016-02-04 | AD21990 | 0.150 ppm |
| 2016-02-04 | AD21992 | 0.0500 ppm |
| 2017-05-03 | AD82299 | 0.630 ppm |
| 2017-05-03 | AD82300 | 0.640 ppm |
| 2017-05-03 | AD82316 | 0.0400 ppm |
| 2017-05-03 | AD82315 | 0.0800 ppm |
| 2017-05-03 | AD82314 | 0.690 ppm |
| 2017-05-03 | AD82317 | 0.0400 ppm |
| 2018-01-29 | AE10843 | 0.400 ppm |
| 2018-01-29 | AE10834 | 0.430 ppm |
| 2018-05-21 | AE26901 | 0.610 ppm |
| 2018-05-21 | AE26899 | ND |
| 2018-05-21 | AE26900 | 0.0400 ppm |
| 2018-09-17 | AE40163 | 0.0600 ppm |
| 2019-02-04 | AE52606 | 0.510 ppm |
| 2019-02-04 | AE52605 | 0.500 ppm |
| 2019-02-04 | AE52602 | ND |
| 2019-02-04 | AE52604 | ND |
| 2019-02-04 | AE52603 | 0.530 ppm |
| 2019-02-04 | AE52607 | ND |