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EWG's Tap Water Database — 2021 UPDATE

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Mercury (inorganic)

Waialee-sunset Beach

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.

 

12

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2014ND40ND
2015ND10ND
2016ND10ND
2017ND30ND
2018ND20ND
2019ND10ND

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 Lab ID Result
2014-02-19201402210361ND
2014-02-20201402220088ND
2014-07-21201407230664ND
2014-07-21201407230666ND
2015-04-28201504300075ND
2016-07-05ND
2017-01-04ND
2017-02-23ND
2017-10-10ND
2018-04-25201804300496ND
2018-08-13201808160452ND
2019-02-19201902210382ND