Chemicals Affecting Cellular Respiration
Metabolic poisons, such as hydrogen cyanide and cyanogen chloride, inhibit cellular respiration, whereby cells extract oxygen from the blood and transform the energy in sugar molecules into a useful form of energy for cells. All systems of the body are ultimately affected by these metabolic poisons. The cardiovascular and central nervous systems are most strongly affected, due to their high demands for oxygen and energy, and their limited ability to use alternative pathways for energy production. Exposure to metabolic poisons can quickly cause seizures, respiratory failure, cardiac arrest, and death. The long-term effects of these agents are poorly understood and may include gradual neurodegeneration.
Metabolic poisons can be inhaled or ingested. Exposure to high concentrations of hydrogencyanide gas (HCN) can cause death within minutes. This narrow therapeutic window presents a formidable challenge for treatment but emphasizes the need for immediate medical intervention. Inhalation of lower concentrations of cyanide vapor or the ingestion of cyanide salt may result in a slower development of symptoms.