EWG's Tap Water Database — 2021 UPDATE


Chromium (total)

Aqua Pa Uwchlan

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
20150.783 ppb38380.250 ppb - 4.50 ppb
20184.62 ppb663.80 ppb - 6.60 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
2015-02-18123952272.20 ppb
2015-02-18123952452.80 ppb
2015-03-17125090093.30 ppb
2015-03-19125090214.50 ppb
2015-03-19125089973.40 ppb
2015-03-20AE695560.440 ppb
2015-03-20AE695550.320 ppb
2015-03-20AE695540.290 ppb
2015-03-20AE695530.350 ppb
2015-03-20AE695520.280 ppb
2015-03-20AE695500.260 ppb
2015-03-20AE695510.280 ppb
2015-03-25AE700000.290 ppb
2015-03-25AE700030.310 ppb
2015-03-25AE699970.280 ppb
2015-05-15AE757120.260 ppb
2015-05-15AE757090.290 ppb
2015-05-15AE757110.260 ppb
2015-05-15AE757100.400 ppb
2015-06-04AE782720.500 ppb
2015-06-04AE782750.470 ppb
2015-08-12131289732.30 ppb
2015-09-16AE927080.430 ppb
2015-09-16AE927160.370 ppb
2015-09-16AE927250.250 ppb
2015-09-16AE927220.350 ppb
2015-09-16AE927000.460 ppb
2015-09-16AE926980.320 ppb
2015-09-16AE927040.440 ppb
2015-09-16AE927190.340 ppb
2015-09-16AE927060.370 ppb
2015-09-16AE927020.330 ppb
2015-09-16AE927280.370 ppb
2015-09-16AE927130.460 ppb
2015-09-16AE926960.350 ppb
2015-09-16AE927100.410 ppb
2015-12-11AF022440.290 ppb
2015-12-11AF022200.430 ppb
2018-01-16AF733653.80 ppb
2018-01-16AF733664.50 ppb
2018-01-29AF744496.60 ppb
2018-01-31AF738194.00 ppb
2018-03-14AF780564.80 ppb
2018-03-14AF780554.00 ppb