Ricin as a weapon: Ricin can be used as a weapon by—
*Releasing it into the air (as a powder or mist) and having people breathe it in (inhalation);
*Putting it into food or water (as a powder or mist) and having people eat or drink it (ingestion); or
*Injecting it into people’s bodies (for example, by using a syringe).
As a weapon of bioterrorism, ricin would most likely be dispersed as an aerosol although contamination of food and water supplies is also feasible. The major reason it is dangerous is that there is no specific antidote, and that it is very easy to obtain (the castor bean plant is a common ornamental, and can be grown at home without any special care). There have been several reported incidents where ricin has been involved with infanticide where small children have been tricked into eating castor beans because of their striking resemblance to chocolate covered coffee beans. Ricin is actually several orders of magnitude less toxic than botulinum or tetanus toxin, but those are more difficult to obtain.