Menu

EWG's Tap Water Database — 2021 UPDATE

Donate

Cobalt

Norwalk Water Department

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

MORE ABOUT THIS CONTAMINANT

 

36

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20130.0667 ppb362ND - 1.20 ppb
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
2013-01-312774507ND
2013-01-312774523ND
2013-01-312774521ND
2013-01-312774515ND
2013-01-312774519ND
2013-01-312774509ND
2013-01-312774505ND
2013-01-312774517ND
2013-01-312774511ND
2013-01-312774527ND
2013-01-312774525ND
2013-01-312774513ND
2013-04-302818648ND
2013-04-302818634ND
2013-04-302818650ND
2013-04-302818632ND
2013-04-302818626ND
2013-04-302818630ND
2013-07-292869295ND
2013-07-2928693761.20 ppb
2013-07-292869342ND
2013-07-292869306ND
2013-07-292869323ND
2013-07-292869372ND
2013-07-292869388ND
2013-07-292869384ND
2013-07-292869380ND
2013-07-292869368ND
2013-07-292869351ND
2013-07-292869360ND
2013-10-2929223031.20 ppb
2013-10-292922290ND
2013-10-292922297ND
2013-10-292922262ND
2013-10-292922271ND
2013-10-292922282ND