Silver toxicity

Background

  • Silver exposure is typically seen in workplace environments, herbal supplements, and other products
  • Exposure is usually topical, but can also include inhalation, and ingestion
  • Common work place environments include
    • Silver nitrate manufacturing
      • Used in manufacturing mirrors, inks, dyes, germicides, antiseptics, and analytical reagents
  • Other possible sources of exposure
    • Acupuncture needles
    • Silver jewelry
    • Herbal supplements
    • Silver sulfadiazine

Clinical Features

  • Typically occur as chronic exposure
  • Skin discoloration (Argyria)
    • Permanent bluish-gray discoloration thought to be due to increased melanin production

Significant Toxicity

  • Rare
  • 50 mg IV is considered fatal
  • Thought to be related to blockade of Na-K-ATPase
  • Pulmonary Edema
  • Hemorrhage
  • Necrosis of bone marrow, liver, and kidneys

Differential Diagnosis

Heavy metal toxicity

Evaluation

  • Usually a clinical diagnosis
  • Serum and urine levels can be sent
    • Serum <1 µg/L (<9 nmol/L)
    • Urine (24 hour) <2 µg/L (<18 nmol/L)

Management

  • Argyria
    • Topical hydroquinone 5%
    • Sunscreen to prevent further pigmentation
  • Silver Ingestion
    • Supportive Care
  • Silver salt ingestion
  • Burns from silver salt

Disposition

  • Discharge unless shows signs of systemic toxicity

References

Lai Becker M., Burns Ewald M. Silver. In: Goldfrank's Toxicologic Emergencies. 9th Ed. New York: McGraw-Hill; 2011: 1321-1325