EWG's Tap Water Database — 2019 UPDATE


Chromium (hexavalent)

City of Chicago

Chromium (hexavalent) is a carcinogen that commonly contaminates American drinking water. Chromium (hexavalent) in drinking water may be due to industrial pollution or natural occurrences in mineral deposits and groundwater. Read more about chromium (hexavalent).





Samples exceeding legal limit (MCL)


Samples exceeding
health guidelines

Testing results - average by year

YearAverage resultSamples takenDetectionsRange of results
20130.230 ppb330.220 ppb - 0.240 ppb
20140.197 ppb12120.180 ppb - 0.220 ppb
20150.188 ppb440.180 ppb - 0.190 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 0.02 ppb

The EWG Health Guideline of 0.02 ppb for chromium (hexavalent) 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 cancer.

ppb = parts per billion

All test results

Date Lab ID Result
2013-10-2329178770.240 ppb
2013-10-2329178750.230 ppb
2013-10-2329178730.220 ppb
2014-04-2830157050.220 ppb
2014-04-2830157380.220 ppb
2014-04-2830157210.210 ppb
2014-04-2830157600.220 ppb
2014-08-1430837580.190 ppb
2014-08-1430837560.190 ppb
2014-08-1430837600.180 ppb
2014-09-0230957160.190 ppb
2014-10-0731189800.180 ppb
2014-10-0731189950.180 ppb
2014-10-0731189700.190 ppb
2014-10-0731189850.190 ppb
2015-01-1331695410.190 ppb
2015-01-1331695370.190 ppb
2015-01-1331693980.180 ppb
2015-01-1331693780.190 ppb