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EWG's Tap Water Database — 2021 UPDATE

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Bromoform

City of Mercer Island

Bromoform, one of the total trihalomethanes (TTHMs), is formed when chlorine or other disinfectants are used to treat drinking water. Bromoform 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

 

88

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
2014ND80ND
2015ND160ND
2016ND160ND
2017ND160ND
2018ND160ND
20190.0313 ppb161ND - 0.500 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 0.5 ppb

The EWG Health Guideline of 0.5 ppb for bromoform was proposed in 2018 by the California Office of Environmental Health Hazard Assessment as a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.

ppb = parts per billion

All test results

Date Lab ID Result
2014-01-1500851ND
2014-01-1500852ND
2014-04-1506587ND
2014-04-1506588ND
2014-07-1712748ND
2014-07-1712747ND
2014-10-1619453ND
2014-10-1619454ND
2015-02-2450801ND
2015-02-2450804ND
2015-02-2450802ND
2015-02-2450803ND
2015-04-1692502ND
2015-04-1692501ND
2015-04-1692504ND
2015-04-1692503ND
2015-07-1441102ND
2015-07-1441101ND
2015-07-1441104ND
2015-07-1441103ND
2015-10-1423003ND
2015-10-1423004ND
2015-10-1423001ND
2015-10-1423002ND
2016-01-13ND
2016-01-13ND
2016-01-13ND
2016-01-13ND
2016-04-14ND
2016-04-14ND
2016-04-14ND
2016-04-14ND
2016-07-13ND
2016-07-13ND
2016-07-13ND
2016-07-13ND
2016-10-11ND
2016-10-11ND
2016-10-11ND
2016-10-11ND
2017-01-10ND
2017-01-10ND
2017-01-10ND
2017-01-10ND
2017-04-12ND
2017-04-12ND
2017-04-12ND
2017-04-12ND
2017-07-11ND
2017-07-11ND
2017-07-11ND
2017-07-11ND
2017-10-10ND
2017-10-10ND
2017-10-10ND
2017-10-10ND
2018-01-10ND
2018-01-10ND
2018-01-10ND
2018-01-10ND
2018-04-10ND
2018-04-10ND
2018-04-10ND
2018-04-10ND
2018-07-10ND
2018-07-10ND
2018-07-10ND
2018-07-17ND
2018-10-11ND
2018-10-11ND
2018-10-11ND
2018-10-11ND
2019-01-09ND
2019-01-09ND
2019-01-09ND
2019-01-09ND
2019-04-11ND
2019-04-11ND
2019-04-11ND
2019-04-11ND
2019-07-10ND
2019-07-10ND
2019-07-10ND
2019-07-10ND
2019-10-170.500 ppb
2019-10-17ND
2019-10-17ND
2019-10-17ND