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EWG's Tap Water Database — 2021 UPDATE

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Nitrite

California Water Service (CWS) - Los Altos Suburban

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.

 

50

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2013N/A00N/A
2014ND70ND
2015ND140ND
2016ND60ND
2017ND30ND
2018ND110ND
2019ND90ND

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
2014-02-135810-029-1337ND
2014-05-125810-029-0915ND
2014-08-045810-029-0840ND
2014-09-095810-011-1250ND
2014-09-105810-016-1125ND
2014-09-105810-010-1019ND
2014-11-065810-029-1125ND
2015-02-035810-013-1115ND
2015-02-035810-015-0916ND
2015-02-035810-021-1002ND
2015-02-125810-029-1100ND
2015-03-055810-022-1100ND
2015-04-095810-008-1100ND
2015-04-095810-020-1201ND
2015-05-075810-029-1300ND
2015-05-135810-018-1347ND
2015-08-045810-023-0948ND
2015-08-045810-035-0915ND
2015-09-155810-057-1240ND
2015-09-155810-032-1220ND
2015-10-065810-002-1300ND
2016-03-235810-028-1120ND
2016-03-235810-030-1140ND
2016-06-155810-024-1245ND
2016-08-095810-037-1310ND
2016-09-075810-029-1322ND
2016-12-125810-029-1115ND
2017-01-115810-010-1245ND
2017-01-115810-011-1300ND
2017-10-115810-016-1215ND
2018-02-125810-013-1230ND
2018-02-125810-021-1415ND
2018-05-085810-018-1335ND
2018-05-165810-023-1020ND
2018-07-105810-008-1305ND
2018-08-085810-022-1335ND
2018-09-185810-057-1225ND
2018-09-185810-032-1320ND
2018-09-185810-035-1347ND
2018-10-105810-002-1431ND
2018-12-265810-020-1420ND
2019-02-205810-029-1240ND
2019-03-195810-030-1343ND
2019-03-195810-028-1357ND
2019-05-295810-029-1500ND
2019-06-185810-024-1336ND
2019-08-195810-029-0839ND
2019-08-205810-037-1125ND
2019-09-115810-029-1418ND
2019-11-195810-029-1130ND