ABSTRACT
Guides for Emergency Response: Biological Agent or Weapon: Ricin AGENT: Ricin is a glycoprotein toxin (66,000 daltons; unit of mass — 1.657 × 10 × 24) from the seed of the castor plant. It blocks protein synthesis by altering the rRNA (any of the various nucleic acids that contain ribose and uracil as structural components and are associated with the control of cellular chemical activities; also called, ribonucleic acid), thus killing the cell. Ricin is a potential biological warfare or terrorist attack agent since it is available throughout the world, is easy to make, and causes extreme pulmonary toxicity when inhaled. It has so far been used only as a weapon of assassination, but when used as an aerosol it could possibly lead to widespread illness and death among victims. It has been said that one milligram of ricin can kill an adult. Abdominal pain, vomiting, and diarrhea symptoms appear in a few hours. Within a few days, there is severe dehydration and a decrease in urine and blood pressure. Th e clinical picture observed is completely dependent on the method of exposure to this biological agent. All reported serious or fatal cases of castor bean ingestion have taken approximately the same course: rapid onset of nausea, vomiting, abdominal cramps and severe diarrhea with vascular collapse; death has occurred on the third day or later. With regard to inhalation, one might expect nonspecifi c symptoms of weakness, fever, cough, and hypothermia followed by hypotension and cardiovascular collapse. High dosages in animals receiving inhalation doses appear to produce severe enough pulmonary damage to produce death.
