Understanding the dangers of Hydrogen Cyanide (HCN)

Early signs are often non-specific and may include central nervous system effects, muscle weakness, neurological disturbances, rapid breathing (tachypnoea), and increased heart rate (tachycardia). In severe cases, symptoms can progress to seizures, sudden loss of consciousness, respiratory and cardiac depression, collapse, pulmonary oedema, and death.

Prolonged exposure to low concentrations may result in non-specific neurological symptoms, thyroid dysfunction, and optic nerve damage. Hydrogen cyanide is not mutagenic and is not classified as a carcinogen.

Source: Hydrogen Cyanide: toxicological overview – GOV.UK

Hydrogen cyanide is widely used in industry as a chemical reagent, particularly in the production of materials such as nylon, acrylates, and acetonitrile. It also has applications in fumigation, pesticides, metal cleaning, ore extraction, electroplating, dyeing, printing, and photography. Small amounts can occur naturally in certain foods, where cyanogenic glycosides in plants such as bitter almonds, cassava, and apricot kernels can release hydrogen cyanide when the plant tissue is damaged or digested.

Most environmental exposure comes from industrial activity and combustion processes, especially fires involving nitrogen-containing materials like plastics. Hydrogen cyanide is a significant toxic component of smoke inhalation in house fires, alongside gases such as carbon monoxide. For the general population, cigarette smoke is the main source of exposure, while ambient air and drinking water levels are generally very low.

Full list of industries below:

• Chemical manufacturing
• Mining and ore extraction
• Electroplating and metal finishing
• Agriculture
• Textiles and dyeing
• Printing and photography
• Plastics and polymers industry