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EWG's Tap Water Database — 2021 UPDATE

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Cobalt

California Water Service (CWS) - Los Altos Suburban

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

 

49

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20130.0457 ppb462ND - 1.10 ppb
2014ND30ND
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
2013-06-04201306060239AMND
2013-06-04201306060116AMND
2013-06-04201306060103AMND
2013-06-05201306060173AMND
2013-06-05201306060218AMND
2013-06-05201306060245AMND
2013-06-10201306110143AMND
2013-06-10201306110394AMND
2013-06-10201306110200AMND
2013-06-10201306110408AMND
2013-06-10201306110154AMND
2013-06-10201306110203AMND
2013-06-10201306110110AMND
2013-06-10201306110089AMND
2013-06-12201306130096AMND
2013-06-13201306140058AMND
2013-06-13201306140050AMND
2013-06-13201306140055AMND
2013-06-18201306190286AM1.000 ppb
2013-06-18201306190264AMND
2013-06-18201306190307AM1.10 ppb
2013-09-11201309120305AMND
2013-09-11201309120299AMND
2013-12-03201312040563AMND
2013-12-03201312040589AMND
2013-12-03201312040597AMND
2013-12-03201312040604AMND
2013-12-03201312040580AMND
2013-12-04201312050166AMND
2013-12-05201312060284AMND
2013-12-09201312100194AMND
2013-12-09201312100211AMND
2013-12-09201312100222AMND
2013-12-09201312100232AMND
2013-12-09201312100255AMND
2013-12-10201312110716AMND
2013-12-10201312110681AMND
2013-12-11201312120623AMND
2013-12-16201312170384AMND
2013-12-16201312170409AMND
2013-12-16201312170438AMND
2013-12-16201312170374AMND
2013-12-16201312170405AMND
2013-12-17201312180736AMND
2013-12-17201312180646AMND
2013-12-18201312200053AMND
2014-03-05201403060204AMND
2014-03-05201403060232AMND
2014-06-04201406050006AMND