Chromium in Drinking Water

If ingested as drinking water, hexavalent chromium (Cr-VI) is likely to be a carcinogen at a certain level, but studies are still being conducted to evaluate what level is unsafe and whether it does cause cancer or not. The best way to reduce chromium-6 is through a reverse osmosis system. It is also known that distillation and anion exchange methods are effective. 

Contaminant  In Water As Maximum Contaminant Level

Chromium (Cr)


Trivalent Cr(III): Cr+3

Hexavalent Cr(VI): Cr2O7-2, CrO4-2

US EPA (for total Chromium):

MCL* = 0.10 mg/L (or ppm)

MCLG** = 0.10 mg/L

WHO† Guideline = 0.05 mg/L


Trivalent chromium is naturally occurring
Hexavalent chromium is produced by certain chemical processses 

Potential Health Effects

  • Nausea, gastrointestinal distress, stomach ulcers, skin ulcers, allergic reactions
  • Kidney and liver damage
  • Reproductive problems
  • Lung and nasal cancer

Treatment Methods

Point-of-Entry (POE)

Point-of-Use (POU)

Reverse Osmosis (TFC, CTA)
Strong and Acid Cation Resin

Reverse Osmosis (TFC, CTA)
Strong Base Anion Resin
Weak Base Anion Resin

Organic Complexes
Reverse Osmosis (TFC, CTA)
Activated Carbon

*Maximum Contaminant Level (MCL): The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to MCLGs as feasible using the best available treatment technology and taking cost into consideration. MCLs are enforceable standards.

**Maximum Contaminant Level Goal (MCLG): The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety and are non-enforceable public health goals.

WHO†: World Health Organization

Click here to open WQA's Technical Fact Sheet on Chromium.

Click here to access all of WQA's Technical Fact Sheets.

Click here to search for products certified to WQAS-300, NSF/ANSI 53 and NSF/ANSI 58 for chromium reduction.