EWG's Tap Water Database — 2019 UPDATE


Chromium (total)

City of Duncanville

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.





Samples exceeding legal limit (MCL)


Samples exceeding
health guidelines

Testing results - average by year

YearAverage resultSamples takenDetectionsRange of results
20130.643 ppb330.521 ppb - 0.707 ppb
20140.278 ppb220.248 ppb - 0.308 ppb
20150.310 ppb660.217 ppb - 0.375 ppb
20160.653 ppb330.480 ppb - 0.770 ppb
20170.433 ppb31ND - 1.30 ppb

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
2014-12-04Q14584500030.308 ppb
2014-12-04Q14584500010.248 ppb
2015-03-18Q15100100030.375 ppb
2015-03-18Q15100100010.361 ppb
2015-06-16Q15222090030.354 ppb
2015-06-16Q15222090010.314 ppb
2015-09-16Q15359340010.217 ppb
2015-09-16Q15359340030.236 ppb