Reactive chemical group

Cyanide

Cyanide compounds have been used in metal finishing, electroplating, coke production, mining, and chemical manufacturing.

Environmental behavior

Persistence and movement

Some cyanide forms degrade or volatilize, while metal-cyanide complexes can persist longer in soil, sediment, or water.

Pathways

How exposure may occur

  • Breathing gas, mist, or contaminated workplace air
  • Drinking or ingesting contaminated water, food, soil, or material
  • Skin contact with concentrated cyanide compounds

People

Potential long-term human effects

  • Cyanide interferes with cells' ability to use oxygen and can be rapidly life-threatening at high doses.
  • Repeated lower exposure may affect the nervous system and thyroid, depending on compound and route.

Other living systems

Potential ecological effects

  • Free cyanide is highly toxic to fish and many aquatic organisms.
  • Wildlife effects depend on concentration, chemical form, and how quickly the compound degrades.

Limits

Important uncertainty

Total cyanide results do not by themselves identify the amount present as more toxic free cyanide.