Ricin


Ricin(Ricinus communis) is classified as a biotoxin, a biological weapon, it is usually in a white powder form, mist or pellet and can be dissolved in water of weak acid. It can be gotten from the seeds of castor bean plant or extracted from the by product of castor oil. Under normal conditions it is a stable substance and can be inactivated by heat at 80? and above. It belongs to the group of toxic plant known as toxalbumin. Ricin is poisonous whenever it is inhaled, ingested or injected, since it can be dissolved in water of weak acid it can be added to a drink. Although ricin cannot be absorbed through skin, it can be poisonous when combined with certain chemicals or if the skin is damaged.
The poison works by inactivating the ribosomes in the cells preventing them from synthesizing proteins. These proteins are needed for survival and reproduction. The estimate lethal dose in humans is 500 mcg (size of the grain of salt or head of a pin)either inhaled or injected. The symptoms of the poison depends on the route of exposure, the dose received and the purification of the substance. When inhaled, the symptoms are usually visible as early as 4-6 hours and late as 24 hours after exposure and they include respiratory distress caused by fluid accumulation in the lungs, fever, nausea, cough tightness in the chest. Low blood pressure and respiratory failure sets in leading to death within 36 – 72 hours after exposure. When ingested, the symptoms are usually vomiting and diarrhea that can become bloody which leads to severe dehydration and low blood pressure, the lining of the stomach and the small intestine becomes inflamed causing bleeding, weakness, excessive thirst, multiple organ failure and finally death. In severe case, liver and renal failure, hallucinations and seizures within 72 hours. When injected,