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EWG's Tap Water Database — 2021 UPDATE

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Monochloroacetic acid

Maynard DPW, Water Division

Monochloroacetic acid, one of the group of five haloacetic acids regulated by federal standards, is formed when chlorine or other disinfectants are used to treat drinking water. Haloacetic acids and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Click here to read more about disinfection byproducts.

 

84

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2014N/A00N/A
20150.981 ppb167ND - 3.00 ppb
20160.770 ppb207ND - 4.20 ppb
20170.263 ppb163ND - 1.90 ppb
2018ND160ND
20190.131 ppb162ND - 1.10 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 53 ppb

The EWG Health Guideline of 53 ppb for monochloroacetic acid was proposed in 2020 by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk.. This health guideline protects against system toxicity.

ppb = parts per billion

All test results

Date Result
2015-03-171.80 ppb
2015-03-171.70 ppb
2015-03-172.00 ppb
2015-03-183.00 ppb
2015-06-16ND
2015-06-16ND
2015-06-162.40 ppb
2015-06-16ND
2015-09-15ND
2015-09-15ND
2015-09-15ND
2015-09-15ND
2015-12-162.40 ppb
2015-12-16ND
2015-12-162.40 ppb
2015-12-16ND
2016-03-10ND
2016-03-10ND
2016-03-10ND
2016-03-102.60 ppb
2016-03-15ND
2016-03-152.00 ppb
2016-03-151.90 ppb
2016-03-154.20 ppb
2016-06-21ND
2016-06-211.30 ppb
2016-06-21ND
2016-06-211.30 ppb
2016-09-21ND
2016-09-212.10 ppb
2016-09-21ND
2016-09-21ND
2016-12-21ND
2016-12-21ND
2016-12-21ND
2016-12-21ND
2017-03-20ND
2017-03-20ND
2017-03-20ND
2017-03-20ND
2017-06-231.90 ppb
2017-06-231.10 ppb
2017-06-23ND
2017-06-231.20 ppb
2017-09-20ND
2017-09-20ND
2017-09-20ND
2017-09-20ND
2017-12-20ND
2017-12-20ND
2017-12-20ND
2017-12-20ND
2018-03-20ND
2018-03-20ND
2018-03-20ND
2018-03-20ND
2018-06-21ND
2018-06-21ND
2018-06-21ND
2018-06-21ND
2018-09-20ND
2018-09-20ND
2018-09-20ND
2018-09-20ND
2018-12-20ND
2018-12-20ND
2018-12-20ND
2018-12-20ND
2019-03-21ND
2019-03-21ND
2019-03-21ND
2019-03-21ND
2019-06-20ND
2019-06-20ND
2019-06-20ND
2019-06-20ND
2019-09-19ND
2019-09-19ND
2019-09-191.10 ppb
2019-09-191.000 ppb
2019-12-18ND
2019-12-18ND
2019-12-18ND
2019-12-18ND