Cadmium toxicity

Background

• Used in electroplating, soldering, pigments, and plastics
• Routes of exposure:
  • Inahlation (up to 25%)
    • Cigarette smoking, occupational exposure
    • Particle size influences the amount absorbed
      • Smaller particles are more likely to penetrate the alveolar-capillary membrane
  • Gastrointestinal (1-10%)
    • Cadmium is ubiquitous in food systems
    • Total daily amount ingested is influenced by a variety of factors
      • Reduced total body iron stores leads to upregulation of the gene that encodes for DMT1, a heavy metal transporter located on the luminal side of enterocytes. Consequently, more cadmium is absorbed from the gastrointestinal tract.
      • In certain parts of Japan, consumption of cadmium ranges from 59 to 113 mcg per day, which is more than twice the daily average of individuals in Europe. This is in large part due to rice irrigated with cadmium-contaminated water.
  • Dermal (less than 1%)
• Distribution
  • Once absorbed, cadmium distributes to most major organs, however it has a predilection for the liver and kidneys

Mechanism of Toxicity

• Inhaled form is 60 times more toxic than ingested form
• Chemical pneumonitis
• Pulmonary edema/hemorrhage
• GI irritation
• Renal tubule damage

Clinical Features

• Local skin and eye irritation
• Cough, wheezing, pulmonary edema
• Nausea, vomiting, diarrhea
• Chronic exposure can lead to bone deposition and "itai-itai" disease

Evaluation

• History of exposure and respiratory / gastrointestinal complaints

Management

Inhalation

• Supplemental oxygen
• Monitor ABG, check CXR
• Treat wheezing and pulmonary edema

Ingestion

• Activated charcoal or lavage
• Volume resuscitation to counter fluid losses
• No role for hemodialysis

See Also

Heavy Metals

References

Olson, K. Poisoning and Drug Overdose, 1999.