Understanding the dangers of Hydrogen Cyanide (HCN)

What is HCN?

Hydrogen cyanide (HCN), sometimes called prussic acid, is a colourless or pale blue gas with a bitter almond-like odour. It is a highly toxic substance that can cause death if inhaled or ingested. HCN is a cellular asphyxiant, which means that it interferes with the body’s ability to use oxygen.

Five facts about Hydrogen cyanide

  • HCN is 35 times more toxic than CO (Carbon monoxide).
  • HCN can enter the body by absorption, inhalation, and ingestion and targets the heart and brain.
  • HCN can cause heart attacks and cardiac arrest, then hamper resuscitation.
  • HCN can cause bizarre and irrational behaviour, hamper the ability to perform a role or to self-rescue, and can hinder or prevent rescue by others.
  • HCN can incapacitate a victim within a short time.

When Hydrogen cyanide enters the body, it binds to a protein called translocase (Cytochrome C oxidase), which is in the mitochondria of cells. Translocase is an essential enzyme that helps cells produce energy. When HCN binds to cytochrome C oxidase, it blocks the enzyme from working, which prevents cells from producing energy.

This lack of energy causes several problems in the body. The brain and heart are particularly sensitive to low oxygen levels, and they can be severely damaged or killed if they are not able to get enough oxygen. Other organs that can be affected include the lungs, kidneys, and liver.

The symptoms of HCN poisoning typically appear within minutes of exposure with initial symptoms that may include headache, dizziness, nausea, vomiting, shortness of breath, and confusion. As the poisoning progresses, the symptoms may become more severe and include seizures, coma, and death.

The severity of the symptoms of poisoning depends on the amount that was inhaled or ingested; a small amount of HCN may cause only mild symptoms, while a large amount can be fatal.

There is no specific antidote for HCN poisoning, but there are treatments that can help to save lives. If someone is exposed, it is important to get them to fresh air immediately. If they are unconscious, medical attention should be sought as soon as possible.

There are several ways to prevent HCN poisoning. These include:

  • Avoiding exposure to HCN-containing substances
  • Using proper safety equipment when handling HCN-containing substances
  • Ensuring that ventilation is adequate in areas where HCN-containing substances are used.
  • Providing training to employees on the hazards of HCN and how to prevent exposure.

Hydrogen cyanide is a dangerous substance, but it can be prevented. By following these safety precautions, you can help to protect your staff from HCN poisoning.

The following table summarises the effects of HCN on the body:

Organ SystemEffects
Central nervous systemHeadache, dizziness, confusion, seizures, coma, death
Cardiovascular systemShortness of breath, rapid heart rate, low blood pressure, cardiac arrest
Pulmonary systemRespiratory distress, difficulty breathing, death
Other organsKidney damage, liver damage

If you are exposed to Hydrogen cyanide, it is important to seek medical attention immediately. There is no specific antidote for HCN poisoning, but there are treatments that can help to save lives.

For further information, help or advice on acquiring the correct safety equipment, call our team on 02920 759 683 or click here to visit our contact page.

Author: Len Bridgeman


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