Menu

EWG's Tap Water Database — 2019 UPDATE

Donate

Chromium (total)

Carroll-Boone Water District

Chromium is a naturally occurring metal, but industrial uses can elevate its levels in water. One form, hexavalent chromium, causes cancer. Total chromium is not a good indicator of the amount of hexavalent chromium in drinking water.

 

6

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2012ND10ND
2013ND10ND
2014ND10ND
2015ND10ND
2016ND10ND
2017ND10ND

ppb = parts per billion

State and national drinking water standards and health guidelines

EPA Maximum Contaminant
Level (MCL) 100 ppb

The legal limit for total chromium, established in 1991, was based on a 1958 toxicity study in laboratory animals, and applies to both the less-toxic trivalent chromium and the more-toxic hexavalent chromium forms of this compound. This limit does not protect against the risk of cancer from ingestion of hexavalent chromium.

ppb = parts per billion

All test results

Date Lab ID Result
2012-04-18121110003ND
2013-04-09131020003ND
2014-04-07141000029ND
2015-05-12Y151350001ND
2016-04-19Y161120013ND
2017-04-27Y171180007ND