This webpage is maintained by the Centers for Disease Control and Prevention (CDC). The webpage provides information and resources on Ricin. Sections of the webpage include: "Updates about the current situation"; "Basics About Ricin"; "Info for Professionals"; and "Learn How to Protect Yourself". "Ricin is a poison found naturally in castor beans. If castor beans are chewed and swallowed, the released ricin can cause injury. Ricin can be made from the waste material left over from processing castor beans. [...] It can be in the form of a powder, a mist, or a pellet, or it can be dissolved in water or weak acid. [...] It is a stable substance under normal conditions, but can be inactivated by heat above 80 degrees centigrade (176 degrees Fahrenheit)."
Centers for Disease Control and Prevention: http://www.cdc.gov/