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EWG's Tap Water Database — 2021 UPDATE

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Cobalt

Contra Costa Water District

Cobalt is a metal found throughout the environment; people may be exposed to cobalt in air, food and drinking water.

 

12

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2013ND120ND
2014N/A00N/A
2015N/A00N/A
2016N/A00N/A
2017N/A00N/A
2018N/A00N/A
2019N/A00N/A

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 70 ppb

The EWG Health Guideline of 70 ppb for cobalt was defined by the Environmental Protection Agency as a benchmark for testing under the Unregulated Contaminant Monitoring Rule program. This health guideline protects against change in blood chemistry.

ppb = parts per billion

All test results

Date Lab ID Result
2013-03-12201303130386AMND
2013-03-12201303130365AMND
2013-03-20201303210135AMND
2013-06-11201306120211AMND
2013-06-12201306130196AMND
2013-06-12201306130200AMND
2013-09-10201309110439AMND
2013-09-11201309120475AMND
2013-09-11201309120291AMND
2013-12-10201312120835AMND
2013-12-11201312120652AMND
2013-12-11201312120837AMND