How does Cadmium get into your water?
Cadmium occurs naturally in many ores. For example Zinc, Lead and Copper ores can contain cadmium. It is also often found in coal and other fossil fuels. Furthermore Cadmium can be found in shales and is released during volcanic activities.
These deposits can serve as sources to ground and surface waters, especially when in contact with low total dissolved solids (TDS) and acidic waters.
Major industrial releases of Cadmium are due to waste streams and leaching of landfills. It is also produced as a by product of a variety of operations that involve Cadmium and/or Zinc. These may include many different types of industrial
operations.
Cadmium is often found in drinking water supplies as a result of deterioration of galvanized plumbing, along with industrial waste contamination, or surface water contamination by certain fertilizers...
Although it is possible for trace Cadmium to be chelated or sequestered as with any metal, it will generally be found in the dissolved ionic form.
Food is the major source of Cadmium in Humans. Leafy vegetables contain approximately 0.05 – 0.12 mg Cadmium/kg.
The Health Implications of Cadmium
Most test and countries monitoring Cadmium levels have established a Maximum Contaminant Level of around 0.005 milligrams per liter (mg/L) for Cadmium in drinking water.
Cadmium has the potentially to cause a variety of effects from acute exposures, including:
- nausea
- vomiting
- diarrhea
- muscle cramps
- salivation
- sensory disturbances
- liver injury
- convulsions
- shock
- renal failure
Drinking water levels which are considered "safe" for short-term exposures are:
- 0.04 mg/L for a 10kg (22 lb.) child consuming 1 liter of water per day for one-to ten-day exposures and 0.005 mg/L for a longer-term (up to 7 years) exposure.
