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EWG's Tap Water Database — 2021 UPDATE

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Thallium

Marco Rural Water Company

Thalium is a naturally occurring metal released into the environment from metal smelting and coal burning. Exposure to too much thalium can cause hair loss, liver damage, reduced sperm motility and nervous system impairment.

 

16

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
2014N/A00N/A
2015N/A00N/A
2016ND80ND
2017N/A00N/A
2018N/A00N/A
2019ND80ND

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 0.1 ppb

The EWG Health Guideline of 0.1 ppb for thallium 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 thallium, established in 1992, was based on analytical detection limits at the time that the standard was set.

ppb = parts per billion

All test results

Date Lab ID Result
2016-03-09AD72144ND
2016-11-08AD85399ND
2016-11-08AD85416ND
2016-11-08AD85401ND
2016-11-08AD85412ND
2016-11-08AD85395ND
2016-11-08AD85422ND
2016-11-08AD85403ND
2019-12-02AE40915ND
2019-12-02AE40929ND
2019-12-03AE41076ND
2019-12-03AE41048ND
2019-12-03AE41049ND
2019-12-03AE41070ND
2019-12-03AE41072ND
2019-12-03AE41074ND