Ricin is a toxin that can be made from the waste left over from processing castor beans. It is one of the most toxic and easily produced plant toxins. If injected, as little as 500 micrograms of ricin could be enough to kill an adult; some animal research indicates that similar amounts could be lethal, if inhaled. A 500 microgram dose of ricin would be about the size of the head of a pin. Ricin has been used in the past as a bioterrorist weapon and remains a serious threat.
This section highlights OSHA standards, preambles to final rules (background to final rules), and directives (instructions for compliance officers) generally applicable to emergency response activities associated with a bioterrorist attack. Refer to the Emergency Preparedness and Response Safety and Health Topics Page for additional information.
Note: Twenty-five states, Puerto Rico and the Virgin Islands have OSHA-approved State Plans and have adopted their own standards and enforcement policies. For the most part, these States adopt standards that are identical to Federal OSHA. However, some States have adopted different standards applicable to this topic or may have different enforcement policies.
Preambles to Final Rules
The discovery of ricin on a mail-opening machine closed three Senate office buildings in early February, 2004. Although no illnesses or deaths resulted, using ricin as a bioterrorist weapon in the workplace remains a serious threat. The following references aid in recognizing disease characteristics and hazards associated with ricin.
Ricin as a Weapon
Ricin may have significance as a biological weapon since it is easy to produce and is stable. In addition to being found on the US Capital, the ricin toxin has also been used or suspected during the following instances:
Related Safety and Health Topics Pages
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