Menu

EWG's Tap Water Database — 2019 UPDATE

Donate

Mercury (inorganic)

Massachusetts Water Resources Authority (MWRA)

Mercury is a potent neurotoxin that also damages the kidneys and other internal organs. Mercury enters drinking water from industrial pollution, mining wastes and coal-fired power plants.

 

48

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20120.00125 ppb81ND - 0.01000 ppb
2013ND80ND
2014ND80ND
2015ND80ND
2016ND80ND
2017ND80ND

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 1.2 ppb

The EWG Health Guideline of 1.2 ppb for mercury (inorganic) was defined 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 harm to internal organs.

EPA Maximum Contaminant
Level (MCL) 2 ppb

The legal limit for inorganic mercury, established in 1991, was based on toxicity studies conducted in laboratory animals in the 1970s and 1980s. This limit does not include any additional consideration of children’s health.

ppb = parts per billion

All test results

Date Result
2012-01-09ND
2012-01-10ND
2012-04-02ND
2012-04-02ND
2012-07-09ND
2012-07-10ND
2012-10-010.01000 ppb
2012-10-02ND
2013-01-07ND
2013-01-08ND
2013-04-01ND
2013-04-02ND
2013-07-09ND
2013-07-09ND
2013-10-07ND
2013-10-08ND
2014-01-06ND
2014-01-07ND
2014-04-07ND
2014-04-07ND
2014-07-07ND
2014-07-08ND
2014-10-06ND
2014-10-07ND
2015-01-05ND
2015-01-06ND
2015-04-06ND
2015-04-07ND
2015-07-06ND
2015-07-07ND
2015-10-06ND
2015-10-06ND
2016-01-05ND
2016-01-05ND
2016-04-05ND
2016-04-05ND
2016-07-05ND
2016-07-05ND
2016-10-04ND
2016-10-04ND
2017-01-03ND
2017-01-03ND
2017-04-04ND
2017-04-04ND
2017-07-11ND
2017-07-11ND
2017-10-03ND
2017-10-03ND