Nitrite
Bethesda WSC
Nitrite, closely related to the fertilizer chemical nitrate, comes from urban runoff and from fertilizer applied to agricultural lands to pollute drinking water. Nitrite is significantly more toxic than nitrate. Excessive nitrite in water can cause oxygen deprivation in infants and increase the risk of cancer.
Testing results - average by year
Year | Average result | Samples taken | Detections | Range of results |
---|---|---|---|---|
2013 | N/A | 0 | 0 | N/A |
2014 | ND | 5 | 0 | ND |
2015 | 0.0481 ppm | 16 | 1 | ND - 0.770 ppm |
2016 | ND | 2 | 0 | ND |
2017 | 0.339 ppm | 5 | 5 | 0.0775 ppm - 0.471 ppm |
2018 | 0.0953 ppm | 4 | 3 | ND - 0.212 ppm |
2019 | 0.153 ppm | 5 | 3 | ND - 0.412 ppm |
ppm = parts per million
State and national drinking water standards and health guidelines
EPA Maximum Contaminant
Level (MCL) 1 ppm
The legal limit for nitrite, established in 1991, was based on the rate of conversion of ingested nitrate into nitrite in adults. This limit may not fully protect against the risk of cancer due to nitrite exposure.
ppm = parts per million
All test results
Date | Lab ID | Result |
---|---|---|
2014-10-07 | Q1451274003 | ND |
2014-11-19 | Q1456730004 | ND |
2014-11-19 | Q1456730003 | ND |
2014-11-19 | Q1456730002 | ND |
2014-11-19 | Q1456730001 | ND |
2015-02-03 | Q1504044004 | ND |
2015-04-22 | Q1515039018 | ND |
2015-04-22 | Q1515039009 | 0.770 ppm |
2015-04-22 | Q1515039010 | ND |
2015-04-22 | Q1515039011 | ND |
2015-04-22 | Q1515039012 | ND |
2015-04-22 | Q1515039013 | ND |
2015-04-22 | Q1515039014 | ND |
2015-04-22 | Q1515039016 | ND |
2015-04-22 | Q1515039017 | ND |
2015-04-22 | Q1515039019 | ND |
2015-04-22 | Q1515039020 | ND |
2015-06-17 | Q1522819001 | ND |
2015-08-04 | Q1530163003 | ND |
2015-08-04 | Q1530163001 | ND |
2015-08-04 | Q1530163002 | ND |
2016-09-06 | Q1635394005 | ND |
2016-10-20 | Q1644787021 | ND |
2017-01-31 | Q1704122008 | 0.0775 ppm |
2017-04-18 | Q1715805001 | 0.298 ppm |
2017-07-18 | Q1729512001 | 0.397 ppm |
2017-10-17 | Q1753293005 | 0.471 ppm |
2017-10-17 | Q1753293026 | 0.453 ppm |
2018-02-21 | Q1807322003 | ND |
2018-05-16 | Q1819957035 | 0.212 ppm |
2018-07-25 | Q1829607001 | 0.0501 ppm |
2018-10-15 | Q1840833001 | 0.119 ppm |
2019-01-15 | Q1901990017 | 0.0581 ppm |
2019-04-11 | Q1914886029 | ND |
2019-08-06 | Q1951620001 | 0.293 ppm |
2019-09-26 | Q1969539001 | 0.412 ppm |
2019-12-18 | Q1980810001 | ND |