Nitrate
Bethesda WSC
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 | 0.457 ppm | 16 | 16 | 0.0490 ppm - 1.26 ppm |
| 2015 | 0.310 ppm | 16 | 15 | ND - 0.826 ppm |
| 2016 | 0.402 ppm | 16 | 16 | 0.0590 ppm - 0.925 ppm |
| 2017 | 0.325 ppm | 16 | 16 | 0.0570 ppm - 0.685 ppm |
| 2018 | 0.228 ppm | 16 | 15 | ND - 0.800 ppm |
| 2019 | 0.271 ppm | 13 | 13 | 0.0288 ppm - 0.702 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 |
|---|---|---|
| 2014-10-07 | Q1451274014 | 0.0490 ppm |
| 2014-10-07 | Q1451274003 | 1.13 ppm |
| 2014-10-07 | Q1451274004 | 0.279 ppm |
| 2014-10-07 | Q1451274005 | 0.134 ppm |
| 2014-10-07 | Q1451274006 | 0.297 ppm |
| 2014-10-07 | Q1451274007 | 0.160 ppm |
| 2014-10-07 | Q1451274008 | 1.26 ppm |
| 2014-10-07 | Q1451274009 | 0.776 ppm |
| 2014-10-07 | Q1451274010 | 0.0840 ppm |
| 2014-10-07 | Q1451274011 | 0.314 ppm |
| 2014-10-07 | Q1451274012 | 1.21 ppm |
| 2014-10-07 | Q1451274013 | 1.12 ppm |
| 2014-11-19 | Q1456730004 | 0.142 ppm |
| 2014-11-19 | Q1456730003 | 0.0660 ppm |
| 2014-11-19 | Q1456730002 | 0.0935 ppm |
| 2014-11-19 | Q1456730001 | 0.202 ppm |
| 2015-02-03 | Q1504044004 | 0.104 ppm |
| 2015-04-22 | Q1515039014 | 0.826 ppm |
| 2015-04-22 | Q1515039009 | 0.238 ppm |
| 2015-04-22 | Q1515039010 | 0.584 ppm |
| 2015-04-22 | Q1515039011 | 0.0885 ppm |
| 2015-04-22 | Q1515039012 | 0.824 ppm |
| 2015-04-22 | Q1515039013 | ND |
| 2015-04-22 | Q1515039016 | 0.771 ppm |
| 2015-04-22 | Q1515039017 | 0.124 ppm |
| 2015-04-22 | Q1515039018 | 0.120 ppm |
| 2015-04-22 | Q1515039019 | 0.0720 ppm |
| 2015-04-22 | Q1515039020 | 0.128 ppm |
| 2015-06-17 | Q1522819001 | 0.0355 ppm |
| 2015-08-04 | Q1530163003 | 0.0550 ppm |
| 2015-08-04 | Q1530163001 | 0.502 ppm |
| 2015-08-04 | Q1530163002 | 0.480 ppm |
| 2016-02-17 | Q1607185002 | 0.679 ppm |
| 2016-02-17 | Q1607185001 | 0.155 ppm |
| 2016-03-21 | Q1611366001 | 0.729 ppm |
| 2016-04-20 | Q1615721013 | 0.674 ppm |
| 2016-04-20 | Q1615721012 | 0.925 ppm |
| 2016-04-20 | Q1615721011 | 0.164 ppm |
| 2016-10-20 | Q1644787017 | 0.0605 ppm |
| 2016-10-20 | Q1644787020 | 0.780 ppm |
| 2016-10-20 | Q1644787016 | 0.292 ppm |
| 2016-10-20 | Q1644787002 | 0.770 ppm |
| 2016-11-08 | Q1648213005 | 0.107 ppm |
| 2016-11-08 | Q1648213017 | 0.652 ppm |
| 2016-11-08 | Q1648213016 | 0.0940 ppm |
| 2016-11-08 | Q1648213007 | 0.114 ppm |
| 2016-11-08 | Q1648213006 | 0.0590 ppm |
| 2016-11-08 | Q1648213004 | 0.178 ppm |
| 2017-01-31 | Q1704122020 | 0.594 ppm |
| 2017-01-31 | Q1704122019 | 0.268 ppm |
| 2017-10-17 | Q1753293024 | 0.121 ppm |
| 2017-10-17 | Q1753293013 | 0.0600 ppm |
| 2017-10-17 | Q1753293043 | 0.685 ppm |
| 2017-10-17 | Q1753293042 | 0.684 ppm |
| 2017-10-17 | Q1753293012 | 0.0980 ppm |
| 2017-10-17 | Q1753293041 | 0.537 ppm |
| 2017-11-01 | Q1756223043 | 0.0645 ppm |
| 2017-11-01 | Q1756223005 | 0.511 ppm |
| 2017-11-01 | Q1756223028 | 0.467 ppm |
| 2017-11-01 | Q1756223006 | 0.0570 ppm |
| 2017-11-01 | Q1756223011 | 0.473 ppm |
| 2017-11-01 | Q1756223037 | 0.318 ppm |
| 2017-11-01 | Q1756223012 | 0.138 ppm |
| 2017-11-01 | Q1756223038 | 0.120 ppm |
| 2018-02-21 | Q1807322003 | 0.162 ppm |
| 2018-05-16 | Q1819957030 | ND |
| 2018-05-16 | Q1819957026 | 0.104 ppm |
| 2018-05-16 | Q1819957027 | 0.0901 ppm |
| 2018-05-16 | Q1819957028 | 0.0973 ppm |
| 2018-05-16 | Q1819957029 | 0.512 ppm |
| 2018-05-16 | Q1819957031 | 0.0275 ppm |
| 2018-05-16 | Q1819957032 | 0.696 ppm |
| 2018-05-16 | Q1819957033 | 0.0507 ppm |
| 2018-05-16 | Q1819957034 | 0.0642 ppm |
| 2018-10-19 | Q1842052008 | 0.122 ppm |
| 2018-10-19 | Q1842052007 | 0.0685 ppm |
| 2018-10-19 | Q1842052006 | 0.223 ppm |
| 2018-10-19 | Q1842052005 | 0.800 ppm |
| 2018-10-19 | Q1842052004 | 0.0335 ppm |
| 2018-10-19 | Q1842052003 | 0.600 ppm |
| 2019-01-15 | Q1901990017 | 0.232 ppm |
| 2019-01-15 | Q1901990011 | 0.0289 ppm |
| 2019-01-15 | Q1901990012 | 0.0288 ppm |
| 2019-04-11 | Q1914886028 | 0.623 ppm |
| 2019-04-11 | Q1914886027 | 0.702 ppm |
| 2019-04-11 | Q1914886026 | 0.0818 ppm |
| 2019-04-11 | Q1914886025 | 0.344 ppm |
| 2019-04-11 | Q1914886024 | 0.0527 ppm |
| 2019-04-11 | Q1914886023 | 0.134 ppm |
| 2019-04-11 | Q1914886022 | 0.136 ppm |
| 2019-09-26 | Q1969539001 | 0.337 ppm |
| 2019-10-07 | Q1971784002 | 0.404 ppm |
| 2019-10-07 | Q1971784009 | 0.418 ppm |