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EWG's Tap Water Database — 2021 UPDATE

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Monochloroacetic acid

Massachusetts Water Resources Authority (MWRA)

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.

MORE ABOUT THIS CONTAMINANT

 

629

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20140.182 ppb242ND - 2.31 ppb
20150.275 ppb15218ND - 3.10 ppb
20160.139 ppb1288ND - 2.61 ppb
20170.372 ppb12820ND - 3.43 ppb
20182.45 ppb6551ND - 5.83 ppb
20191.73 ppb13281ND - 5.28 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
2014-01-06ND
2014-01-07ND
2014-02-032.06 ppb
2014-02-042.31 ppb
2014-03-03ND
2014-03-03ND
2014-04-07ND
2014-04-07ND
2014-05-05ND
2014-05-05ND
2014-06-02ND
2014-06-06ND
2014-07-07ND
2014-07-08ND
2014-08-05ND
2014-08-05ND
2014-09-09ND
2014-09-09ND
2014-10-06ND
2014-10-07ND
2014-11-04ND
2014-11-04ND
2014-12-01ND
2014-12-02ND
2015-01-05ND
2015-01-06ND
2015-02-02ND
2015-02-03ND
2015-02-17ND
2015-02-17ND
2015-02-17ND
2015-02-17ND
2015-02-17ND
2015-02-17ND
2015-02-17ND
2015-02-17ND
2015-02-17ND
2015-02-18ND
2015-02-18ND
2015-02-18ND
2015-02-18ND
2015-02-18ND
2015-02-18ND
2015-02-18ND
2015-02-18ND
2015-02-18ND
2015-02-18ND
2015-02-18ND
2015-02-19ND
2015-02-19ND
2015-02-19ND
2015-02-19ND
2015-02-19ND
2015-02-19ND
2015-02-19ND
2015-02-19ND
2015-02-19ND
2015-02-19ND
2015-02-19ND
2015-02-19ND
2015-03-02ND
2015-03-03ND
2015-04-06ND
2015-04-07ND
2015-05-04ND
2015-05-04ND
2015-05-18ND
2015-05-182.04 ppb
2015-05-18ND
2015-05-18ND
2015-05-182.08 ppb
2015-05-182.57 ppb
2015-05-19ND
2015-05-192.07 ppb
2015-05-192.02 ppb
2015-05-192.88 ppb
2015-05-19ND
2015-05-19ND
2015-05-192.37 ppb
2015-05-19ND
2015-05-192.01 ppb
2015-05-202.29 ppb
2015-05-202.33 ppb
2015-05-20ND
2015-05-20ND
2015-05-202.18 ppb
2015-05-202.37 ppb
2015-05-20ND
2015-05-20ND
2015-05-21ND
2015-05-21ND
2015-05-21ND
2015-05-21ND
2015-05-21ND
2015-05-21ND
2015-05-212.42 ppb
2015-05-21ND
2015-05-222.10 ppb
2015-06-01ND
2015-06-02ND
2015-07-06ND
2015-07-07ND
2015-08-03ND
2015-08-04ND
2015-08-17ND
2015-08-17ND
2015-08-17ND
2015-08-17ND
2015-08-17ND
2015-08-17ND
2015-08-17ND
2015-08-172.82 ppb
2015-08-17ND
2015-08-18ND
2015-08-18ND
2015-08-18ND
2015-08-183.10 ppb
2015-08-18ND
2015-08-18ND
2015-08-182.12 ppb
2015-08-19ND
2015-08-19ND
2015-08-19ND
2015-08-19ND
2015-08-19ND
2015-08-19ND
2015-08-19ND
2015-08-19ND
2015-08-20ND
2015-08-20ND
2015-08-20ND
2015-08-20ND
2015-08-20ND
2015-08-20ND
2015-08-20ND
2015-08-20ND
2015-09-08ND
2015-09-08ND
2015-10-05ND
2015-10-06ND
2015-11-02ND
2015-11-03ND
2015-11-16ND
2015-11-16ND
2015-11-16ND
2015-11-16ND
2015-11-16ND
2015-11-16ND
2015-11-16ND
2015-11-162.07 ppb
2015-11-16ND
2015-11-17ND
2015-11-17ND
2015-11-17ND
2015-11-17ND
2015-11-17ND
2015-11-17ND
2015-11-17ND
2015-11-18ND
2015-11-18ND
2015-11-18ND
2015-11-18ND
2015-11-18ND
2015-11-18ND
2015-11-18ND
2015-11-18ND
2015-11-19ND
2015-11-19ND
2015-11-19ND
2015-11-19ND
2015-11-19ND
2015-11-19ND
2015-11-19ND
2015-11-19ND
2015-12-07ND
2015-12-08ND
2016-02-16ND
2016-02-16ND
2016-02-16ND
2016-02-16ND
2016-02-16ND
2016-02-16ND
2016-02-16ND
2016-02-16ND
2016-02-16ND
2016-02-17ND
2016-02-17ND
2016-02-17ND
2016-02-17ND
2016-02-17ND
2016-02-17ND
2016-02-17ND
2016-02-17ND
2016-02-17ND
2016-02-17ND
2016-02-17ND
2016-02-18ND
2016-02-18ND
2016-02-18ND
2016-02-18ND
2016-02-18ND
2016-02-18ND
2016-02-18ND
2016-02-18ND
2016-02-18ND
2016-02-18ND
2016-02-18ND
2016-02-18ND
2016-05-162.61 ppb
2016-05-16ND
2016-05-16ND
2016-05-16ND
2016-05-16ND
2016-05-16ND
2016-05-162.06 ppb
2016-05-16ND
2016-05-162.14 ppb
2016-05-172.14 ppb
2016-05-17ND
2016-05-172.20 ppb
2016-05-17ND
2016-05-17ND
2016-05-17ND
2016-05-17ND
2016-05-18ND
2016-05-18ND
2016-05-18ND
2016-05-18ND
2016-05-18ND
2016-05-18ND
2016-05-18ND
2016-05-18ND
2016-05-19ND
2016-05-19ND
2016-05-19ND
2016-05-19ND
2016-05-19ND
2016-05-19ND
2016-05-19ND
2016-05-19ND
2016-08-152.60 ppb
2016-08-15ND
2016-08-15ND
2016-08-15ND
2016-08-15ND
2016-08-15ND
2016-08-15ND
2016-08-152.10 ppb
2016-08-15ND
2016-08-16ND
2016-08-16ND
2016-08-16ND
2016-08-16ND
2016-08-16ND
2016-08-16ND
2016-08-16ND
2016-08-17ND
2016-08-17ND
2016-08-17ND
2016-08-17ND
2016-08-17ND
2016-08-17ND
2016-08-17ND
2016-08-17ND
2016-08-17ND
2016-08-18ND
2016-08-18ND
2016-08-18ND
2016-08-18ND
2016-08-18ND
2016-08-18ND
2016-08-18ND
2016-11-14ND
2016-11-14ND
2016-11-14ND
2016-11-14ND
2016-11-14ND
2016-11-14ND
2016-11-14ND
2016-11-14ND
2016-11-14ND
2016-11-15ND
2016-11-15ND
2016-11-152.00 ppb
2016-11-15ND
2016-11-15ND
2016-11-15ND
2016-11-15ND
2016-11-16ND
2016-11-16ND
2016-11-16ND
2016-11-16ND
2016-11-16ND
2016-11-16ND
2016-11-16ND
2016-11-16ND
2016-11-16ND
2016-11-17ND
2016-11-17ND
2016-11-17ND
2016-11-17ND
2016-11-17ND
2016-11-17ND
2016-11-17ND
2017-02-13ND
2017-02-13ND
2017-02-13ND
2017-02-13ND
2017-02-13ND
2017-02-13ND
2017-02-13ND
2017-02-13ND
2017-02-13ND
2017-02-14ND
2017-02-14ND
2017-02-14ND
2017-02-14ND
2017-02-14ND
2017-02-14ND
2017-02-14ND
2017-02-15ND
2017-02-15ND
2017-02-15ND
2017-02-15ND
2017-02-15ND
2017-02-15ND
2017-02-15ND
2017-02-15ND
2017-02-16ND
2017-02-16ND
2017-02-16ND
2017-02-16ND
2017-02-16ND
2017-02-16ND
2017-02-16ND
2017-02-16ND
2017-05-152.40 ppb
2017-05-15ND
2017-05-15ND
2017-05-15ND
2017-05-15ND
2017-05-15ND
2017-05-15ND
2017-05-152.06 ppb
2017-05-152.09 ppb
2017-05-162.63 ppb
2017-05-16ND
2017-05-16ND
2017-05-16ND
2017-05-162.04 ppb
2017-05-172.24 ppb
2017-05-17ND
2017-05-17ND
2017-05-17ND
2017-05-17ND
2017-05-17ND
2017-05-172.04 ppb
2017-05-17ND
2017-05-18ND
2017-05-18ND
2017-05-182.57 ppb
2017-05-18ND
2017-05-182.04 ppb
2017-05-18ND
2017-05-18ND
2017-05-18ND
2017-05-18ND
2017-05-182.16 ppb
2017-08-14ND
2017-08-14ND
2017-08-14ND
2017-08-14ND
2017-08-14ND
2017-08-14ND
2017-08-14ND
2017-08-14ND
2017-08-14ND
2017-08-15ND
2017-08-15ND
2017-08-15ND
2017-08-15ND
2017-08-15ND
2017-08-16ND
2017-08-16ND
2017-08-16ND
2017-08-16ND
2017-08-16ND
2017-08-16ND
2017-08-16ND
2017-08-16ND
2017-08-16ND
2017-08-16ND
2017-08-17ND
2017-08-17ND
2017-08-17ND
2017-08-172.25 ppb
2017-08-173.12 ppb
2017-08-17ND
2017-08-173.43 ppb
2017-08-17ND
2017-11-13ND
2017-11-13ND
2017-11-13ND
2017-11-13ND
2017-11-13ND
2017-11-13ND
2017-11-13ND
2017-11-132.43 ppb
2017-11-13ND
2017-11-14ND
2017-11-14ND
2017-11-14ND
2017-11-14ND
2017-11-14ND
2017-11-15ND
2017-11-15ND
2017-11-15ND
2017-11-15ND
2017-11-15ND
2017-11-15ND
2017-11-15ND
2017-11-15ND
2017-11-152.98 ppb
2017-11-15ND
2017-11-162.03 ppb
2017-11-16ND
2017-11-162.21 ppb
2017-11-162.45 ppb
2017-11-162.21 ppb
2017-11-16ND
2017-11-162.29 ppb
2017-11-16ND
2018-05-012.59 ppb
2018-08-135.53 ppb
2018-08-134.89 ppb
2018-08-135.12 ppb
2018-08-14ND
2018-08-142.61 ppb
2018-08-144.70 ppb
2018-08-144.01 ppb
2018-08-142.03 ppb
2018-08-15ND
2018-08-152.04 ppb
2018-08-15ND
2018-08-153.16 ppb
2018-08-152.39 ppb
2018-08-152.96 ppb
2018-08-15ND
2018-08-155.83 ppb
2018-08-162.32 ppb
2018-08-163.05 ppb
2018-08-163.60 ppb
2018-08-16ND
2018-08-16ND
2018-08-162.42 ppb
2018-08-162.83 ppb
2018-08-162.69 ppb
2018-08-162.94 ppb
2018-08-162.16 ppb
2018-08-162.72 ppb
2018-08-163.64 ppb
2018-08-163.46 ppb
2018-08-163.12 ppb
2018-08-162.79 ppb
2018-08-162.53 ppb
2018-11-143.29 ppb
2018-11-14ND
2018-11-14ND
2018-11-142.38 ppb
2018-11-142.12 ppb
2018-11-142.84 ppb
2018-11-142.32 ppb
2018-11-14ND
2018-11-142.79 ppb
2018-11-142.53 ppb
2018-11-142.51 ppb
2018-11-142.62 ppb
2018-11-142.73 ppb
2018-11-142.40 ppb
2018-11-15ND
2018-11-15ND
2018-11-15ND
2018-11-153.34 ppb
2018-11-153.84 ppb
2018-11-153.60 ppb
2018-11-152.61 ppb
2018-11-152.75 ppb
2018-11-15ND
2018-11-154.02 ppb
2018-11-162.70 ppb
2018-11-163.04 ppb
2018-11-162.81 ppb
2018-11-162.67 ppb
2018-11-163.43 ppb
2018-11-163.60 ppb
2018-11-164.05 ppb
2018-11-16ND
2019-02-194.22 ppb
2019-02-192.66 ppb
2019-02-192.95 ppb
2019-02-192.50 ppb
2019-02-193.28 ppb
2019-02-193.43 ppb
2019-02-202.47 ppb
2019-02-203.39 ppb
2019-02-203.53 ppb
2019-02-205.28 ppb
2019-02-202.67 ppb
2019-02-202.82 ppb
2019-02-203.11 ppb
2019-02-204.17 ppb
2019-02-202.98 ppb
2019-02-212.48 ppb
2019-02-213.06 ppb
2019-02-212.91 ppb
2019-02-212.52 ppb
2019-02-212.82 ppb
2019-02-212.99 ppb
2019-02-212.80 ppb
2019-02-213.16 ppb
2019-02-223.75 ppb
2019-02-222.39 ppb
2019-02-223.56 ppb
2019-02-223.62 ppb
2019-02-223.17 ppb
2019-02-223.49 ppb
2019-02-223.75 ppb
2019-02-223.40 ppb
2019-02-223.35 ppb
2019-05-203.09 ppb
2019-05-202.48 ppb
2019-05-20ND
2019-05-202.72 ppb
2019-05-202.13 ppb
2019-05-20ND
2019-05-20ND
2019-05-20ND
2019-05-202.20 ppb
2019-05-202.02 ppb
2019-05-212.87 ppb
2019-05-21ND
2019-05-21ND
2019-05-212.07 ppb
2019-05-222.74 ppb
2019-05-22ND
2019-05-232.68 ppb
2019-05-232.25 ppb
2019-05-232.04 ppb
2019-05-23ND
2019-05-23ND
2019-05-233.58 ppb
2019-05-232.13 ppb
2019-05-23ND
2019-05-23ND
2019-05-232.69 ppb
2019-05-233.03 ppb
2019-05-23ND
2019-05-23ND
2019-05-23ND
2019-05-232.23 ppb
2019-05-242.60 ppb
2019-05-242.52 ppb
2019-05-242.91 ppb
2019-08-192.04 ppb
2019-08-19ND
2019-08-192.53 ppb
2019-08-193.59 ppb
2019-08-193.03 ppb
2019-08-193.34 ppb
2019-08-202.68 ppb
2019-08-20ND
2019-08-20ND
2019-08-202.26 ppb
2019-08-203.34 ppb
2019-08-202.71 ppb
2019-08-202.42 ppb
2019-08-203.00 ppb
2019-08-202.79 ppb
2019-08-22ND
2019-08-222.60 ppb
2019-08-222.89 ppb
2019-08-22ND
2019-08-222.66 ppb
2019-08-223.20 ppb
2019-08-222.36 ppb
2019-08-232.13 ppb
2019-08-23ND
2019-08-23ND
2019-08-23ND
2019-08-23ND
2019-08-232.05 ppb
2019-08-23ND
2019-08-23ND
2019-09-25ND
2019-09-252.03 ppb
2019-09-25ND
2019-11-18ND
2019-11-18ND
2019-11-18ND
2019-11-18ND
2019-11-18ND
2019-11-18ND
2019-11-18ND
2019-11-18ND
2019-11-18ND
2019-11-18ND
2019-11-19ND
2019-11-192.25 ppb
2019-11-19ND
2019-11-19ND
2019-11-19ND
2019-11-20ND
2019-11-20ND
2019-11-202.12 ppb
2019-11-202.21 ppb
2019-11-212.37 ppb
2019-11-21ND
2019-11-212.57 ppb
2019-11-212.55 ppb
2019-11-21ND
2019-11-21ND
2019-11-21ND
2019-11-222.15 ppb
2019-11-22ND
2019-11-22ND
2019-11-22ND
2019-11-222.00 ppb
2019-11-22ND
2019-11-222.37 ppb