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.

There are currently no specific OSHA standards or directives for ricin.

OSHA Standards

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.

General Industry (29 CFR 1910)

• 1910 Subpart E, Exit routes, emergency action plans, and fire prevention plans
  • 1910.38, Emergency action plans [related topic page]
    
  
  
• 1910 Subpart H, Hazardous materials [related topic page]
  • 1910.120, Hazardous waste operations and emergency response [related topic page]
    • 1910.120(q), Emergency response program to hazardous substance releases
      
    
    
• 1910 Subpart I, Personal protective equipment
  • 1910.132, General requirements [related topic pages]
  • 1910.134, Respiratory protection [related topic page]
    • Appendix A, Fit testing procedures (Mandatory)
    • Appendix B-1, User seal check procedures (Mandatory)
    • Appendix B-2, Respiratory cleaning procedures (Mandatory)
    • Appendix C, OSHA respirator medical evaluation questionnaire (Mandatory)
    • Appendix D, Information for employees using respirators when not required under standard (Mandatory)

Preambles to Final Rules

• Hazardous Waste Operations and Emergency Response (1989)
  • Intro to 29 CFR Part 1910, Hazardous Waste Operations and Emergency Response
  • I. Background
  • II. Summary and Explanation of the Standard
  • VII. State Plan States
  • VIII. Federal and State Coverage of the Public Sector and Volunteers
    
  
  
• Search all available preambles to final rules.

Directives

• Inspection Procedures for 29 CFR 1910.120 and 1926.65, Paragraph (q): Emergency Response to Hazardous Substance Releases. CPL 02-02-073, (2007, August 27). Also available as a 444 KB PDF^*, 119 pages. Updates enforcement procedures for compliance officers who need to conduct inspections of emergency response operations. It defines additional terms and expands on training requirements for emergency responders and other groups such as skilled support personnel. This OSHA instruction revises CPL 02-02-059, issued April 24, 1998.
  


• Search all available directives.

Hazard Recognition

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. Centers for Disease Control and Prevention (CDC).
  


• TOXNET for Ricin. The National Library of Medicine Hazardous Substance Database.
  


• Ricin Toxin From Castor Bean Plant, Ricinus communis. Cornell University, (2001, October 4).
  


• CBRNE - Ricin. eMedicine, (2004, February 3).
  


• Medical Management of Biological Casualties Handbook Seventh Edition [2 MB PDF, 254 pages]. US Army Medical Research Institute of Infectious Diseases (USAMRIID), (2011, September). Contains specific information on a number of potential bioterrorist agents.
  


• Office of The Surgeon General, Department of the Army. "Medical Aspects of Chemical and Biological Warfare." Textbook of Military Medicine, Part I. Warfare, Weaponry, and the Casualty, (1997).
  • Chapter 30, Defense Against Toxic Weapons [142 KB PDF, 17 pages].
  • Chapter 32, Ricin Toxin [269 KB PDF, 12 pages].

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:

• Ricin was considered for weaponization by the United States during its offensive Biological Warfare Program. Such a weapon was tested but apparently never used in battle.
  


• Ricin was used in the highly publicized assassination of Bulgarian defector Georgi Markov in 1978. An attacker used an umbrella rigged with a special tip to inject a ricin pellet under Markov's skin.
  


• Some reports have indicated that ricin may have been used in the Iran-Iraq war during the 1980s, and that quantities of ricin were found in Al Qaeda caves in Afghanistan.
  


• Two tax protestors were convicted in 1995 under the Anti-Terrorism Act for possessing ricin as a biological weapon.
  


• A retired electrician was arrested in 1995 under the Anti-Terrorism Act for possessing castor beans. Two years before, a large quantity of ricin toxin, weapons, ammunition, and gold were found in his car by Canadian customs officials as he crossed the border from Alaska to Canada.
  


• In October, 2003, an envelope with a threatening note and a sealed container with ricin was discovered at a mail processing and distribution facility in Greenville, South Carolina. No ricin-associated illnesses were identified as a result of the incident.

Additional Information

Related Safety and Health Topics Pages

• Bioterrorism
  


• Emergency Preparedness and Response

Other Resources

• Evacuation Planning Matrix. OSHA.
  
  
• Report an Emergency. Centers for Disease Control and Prevention (CDC). Recommends that health care professionals contact their local and/or state health department. This link provides a list of health department websites and emergency notification procedures for use by health officials and healthcare providers.

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