Key Points

Fire

• Extremely flammable
• Mixtures of hydrogen cyanide vapour and air may be explosive
• Use foam and liquid-tight protective clothing with breathing apparatus

Health

• Exposure to hydrogen cyanide and its solutions may be fatal by all routes of exposure
• The onset of signs and symptoms following exposure is rapid after inhalation and ingestion
• Features are mostly non-specific and include headache, nausea, dizziness and difficultly breathing
• High concentrations may cause loss of consciousness, abnormal heart rhythm, coma and death
• Long term exposure to low levels of cyanide may affect the nervous system
• Hydrogen cyanide does not have any mutagenic properties and is not considered to be a carcinogen
• Hydrogen cyanide is not considered to be a human reproductive or developmental toxicant

Environment

• Dangerous for the environment
• Inform Environment Agency of substantial incidents

 

All sections are available to download in PDF format.

 

• Hydrogen Cyanide - Full Document (PDF, 203 KB)
  HPA Compendium of Chemical Hazards Hydrogen cyanide, version 3, 2011. This document will be reviewed not later than 3 years or sooner if substantive evidence becomes available.
  Added/updated: 13 January 2012
  
• General Information - Hydrogen cyanide (PDF, 54 KB)
  Hydrogen cyanide General information, version 2, 2007.
  Added/updated: 24 March 2011
  
• Incident Management - Hydrogen cyanide (PDF, 87 KB)
  Hydrogen cyanide Incident management
  Added/updated: 13 January 2012
  
• Toxicological Overview - Hydrogen cyanide (PDF, 87 KB)
  Hydrogen cyanide Toxicological overview, version 2, 2007
  Added/updated: 24 March 2011