Cadmium in Drinking Water

Cadmium occurs naturally in zinc, in lead and copper ores, in coal and other fossil fuels, in shales and is released during volcanic action. These deposits can serve as sources to ground and surface waters, especially when in contact with low total dissolved solids (TDS) and acidic waters. Cadmium has the chronic potential to cause kidney, liver, bone and blood damage from long- term exposure at levels above the maximum contaminant level (MCL). There is inadequate evidence to state whether or not cadmium has the potential to cause cancer from lifetime exposures in drinking water.

 Contaminant In Water As Maximum Contaminant Level


Cadmium (Cd)



MCL* = 0.005 mg/L

MCLG** = 0.005 mg/L

WHO† Guideline = 0.003 mg/L

Sources of Contaminant

  • Corrosion of galvanized pipes
  • Erosion of natural deposits
  • Discharge from metal refineries
  • Runoff from waste batteries and paints 
Potential Health Effects
  • Kidney Damage

Treatment Methods

  • Reverse Osmosis
  • Distillation

*Action Level regulated by the USEPA requires water utilities to sample specific number of samples in specific locations and verify that 90% of samples are below this level. If that is not met, an appropriate Action is required to be taken to remedy the situation.

**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 access WQA's Technical Fact Sheet on Cadmium.