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EWG's Tap Water Database — 2021 UPDATE

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N-Nitrosomethylethylamine

Zone 7 Water Agency

N-Nitrosomethylethylamine is one of the DNA-damaging, cancer-causing contaminants called N-nitrosamines that can form during water treatment with the use of certain disinfectants, such as chloramine. Read More.

Pollution of water sources with effluent from municipal wastewater treatment plants and runoff from animal feeding operations contributes to nitrosamine formation. Fifteen different nitrosamines are listed as carcinogens in the U.S. Department of Health and Human Services National Toxicology Program Report on Carcinogens. The federal government has not set a legal limit for nitrosamines in drinking water and water utilities typically do not test for these contaminants. California has set a public health goal for one of the most common nitrosamines, N-nitrosodimethylamine or NDMA, at 0.003 parts per billion in drinking water, a concentration that corresponds to an estimated one-in-one-million cancer risk.

 

15

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2014ND50ND
2015ND20ND
2016ND20ND
2017ND20ND
2018ND20ND
2019ND20ND

ppb = parts per billion

All test results

Date Lab ID Result
2014-08-139590-001-0735ND
2014-08-139590-008-0945ND
2014-09-189590-001-1135ND
2014-09-189590-008-1110ND
2014-10-159590-008-1035ND
2015-08-129590-001-0835ND
2015-08-129590-008-1010ND
2016-08-039590-001-1230ND
2016-08-039590-008-1020ND
2017-08-169590-001-0825ND
2017-08-169590-008-0955ND
2018-08-079590-001-0940ND
2018-08-079590-008-0950ND
2019-08-079590-001-1345ND
2019-08-079590-008-1240ND