Ricin Health Dictionary

n. a highly toxic albumin obtained from castor-oil seeds (Ricinus communis) that inhibits protein synthesis and becomes attached to the surface of cells, resulting in gastroenteritis, hepatic congestion and jaundice, and cardiovascular collapse. It is lethal to most species, even in minute amounts (1 ?g/kg body weight); it is most toxic if injected intravenously or inhaled as fine particles. Ricin is being investigated as a treatment for certain lymphomas, which depends on its delivery to the exact site of the tumour in order to avoid destruction of healthy cells (see immunotoxin).