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EWG's Tap Water Database — 2021 UPDATE

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Mercury (inorganic)

San Antonio Water System

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.

MORE ABOUT THIS CONTAMINANT

 

96

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2014ND40ND
2015N/A00N/A
2016ND370ND
2017ND210ND
2018ND10ND
2019ND330ND

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
2014-05-13AC53956ND
2014-07-29AC61321ND
2014-09-02AC65419ND
2014-11-25AC72964ND
2016-01-13AD17796ND
2016-04-05AD31783ND
2016-04-05AD31777ND
2016-04-05AD31781ND
2016-04-05AD31785ND
2016-04-05AD31782ND
2016-04-06AD31988ND
2016-04-06AD31987ND
2016-04-07AD32239ND
2016-04-07AD32233ND
2016-04-07AD32223ND
2016-04-07AD32224ND
2016-04-07AD32229ND
2016-04-07AD32228ND
2016-06-28AD42066ND
2016-10-06AD52618ND
2016-10-06AD52617ND
2016-10-31AD55376ND
2016-10-31AD55375ND
2016-11-02AD56052ND
2016-11-02AD56058ND
2016-11-02AD56057ND
2016-11-02AD56056ND
2016-11-03AD56403ND
2016-11-03AD56408ND
2016-11-03AD56407ND
2016-11-04AD56736ND
2016-11-04AD56737ND
2016-11-28AD59164ND
2016-11-28AD59158ND
2016-11-28AD59163ND
2016-11-28AD59162ND
2016-11-28AD59161ND
2016-11-29AD59309ND
2016-11-29AD59314ND
2016-11-29AD59302ND
2016-11-29AD59301ND
2017-01-30AD67445ND
2017-01-30AD67441ND
2017-01-30AD67452ND
2017-02-02AD68311ND
2017-03-06AD73385ND
2017-03-06AD73384ND
2017-03-29AD77384ND
2017-03-29AD77380ND
2017-03-29AD77371ND
2017-03-29AD77379ND
2017-03-29AD77381ND
2017-03-30AD77695ND
2017-03-30AD77693ND
2017-03-30AD77696ND
2017-07-06AD88424ND
2017-07-06AD88423ND
2017-10-17AE00988ND
2017-12-04AE06516ND
2017-12-05AE06722ND
2017-12-05AE06721ND
2017-12-08AE07388ND
2018-03-01AE16254ND
2019-01-30AE52135ND
2019-01-31AE52378ND
2019-01-31AE52377ND
2019-03-07AE57535ND
2019-03-07AE57534ND
2019-03-28AE60415ND
2019-03-28AE60416ND
2019-04-23AE63297ND
2019-04-23AE63298ND
2019-04-25AE63669ND
2019-04-25AE63670ND
2019-05-21AE67304ND
2019-05-21AE67307ND
2019-05-21AE67306ND
2019-05-21AE67305ND
2019-08-13AE78239ND
2019-11-13AE89065ND
2019-11-14AE89235ND
2019-11-14AE89229ND
2019-11-14AE89236ND
2019-11-14AE89232ND
2019-11-25AE90340ND
2019-11-25AE90344ND
2019-11-25AE90341ND
2019-11-25AE90343ND
2019-11-25AE90342ND
2019-11-26AE90540ND
2019-11-26AE90541ND
2019-12-10AE91812ND
2019-12-10AE91811ND
2019-12-10AE91813ND
2019-12-11AE92086ND
2019-12-11AE92082ND