The many uses of ricin for basic research and clinical studies have ma
de it an intensively studied molecule. Although the exact mechanism by
which the toxin kills animals is unknown, ricin kills cells by enteri
ng the cytosol and inhibiting protein synthesis. In all areas of clini
cal use, forensic medicine, and basic scientific inquiry, the capabili
ty to detect the toxin is of primary importance. Recent efforts to pro
duce a vaccine originate from a perception that this widely available
toxic plant protein could be a poor man's weapon of mass destruction.