Potassium cyanide is a compound with the formula KCN. This colorless crystalline salt, similar in appearance to sugar, is highly soluble in water. Most KCN is used in gold mining, organic synthesis, and electroplating. Smaller applications include jewellery for chemical gilding and buffing.
Exposure to potassium cyanide can be rapidly fatal. It has whole-body (systemic) effects, particularly affecting those organ systems most sensitive to low oxygen levels: the central nervous system (brain), the cardiovascular system (heart and blood vessels), and the pulmonary system (lungs).
Cyanide is a highly cytotoxic poison and its intoxication may be acute or chronic. Acute intoxication is lethal if not immediately diagnosed and treated within 30 minutes.
Cyanide prevents the cells of the body from using oxygen. When this happens, the cells die. Cyanide is more harmful to the heart and brain than to other organs because the heart and brain use a lot of oxygen.