What You Need to Know about Ricin

Responders to hazmat and WMD incidents who have been active since 911 are well aware of what happened in the wake of the anthrax attack in 2011. Thousands of anthrax scares kept hazmat teams scurrying to “white powder” calls, almost all of which turned out to be harmless substances. The newest scourge involves another biological agent - ricin.

Ricin letters have been sent to the President, a US Senator and New York’s Mayor Bloomberg, and the organization Mayors Against Illegal Guns. The letters attack the stance of persons and organizations who back stricter gun control legislation.


Capture Terrorist planting a powdered biological weapon.


When the anthrax attacks happened, news organizations worldwide turned to Emergency
Film Group because it had recently release a training film called Response to Anthrax Threats. As is the case now with ricin, little was known about anthrax.

In 2001, letters containing anthrax were sent to Senator Tom Daschle, NBC and other media outlets. The anthrax had been weaponized and milled to very fine dust. In the aftermath, there were nineteen confirmed cases of anthrax and five persons died. Many more were exposed and underwent treatment. Anthrax can kill up to 90% of its victims.  The most likely and most lethal route of exposure is through inhalation. Within one week of exposure acute respiratory distress and cyanosis may appear. A vaccine is available and certain antibiotics can be effective immediately after exposure. However, there is usually no effective treatment after symptoms begin.

In WMD training for emergency responders, biological agents are usually divided into four major categories: Viruses, Bacteria, Toxins, and Rickettsia.  Anthrax is categorized as bacteria, while ricin is a toxin.

Biological toxins are produced by plants, animals, or microorganisms. Ricin is a protein found in the castor bean plant. The plant (ricinus communis), generally found in areas with a year-round warm climate, is a fast-growing leafy plant that can grow ten feet in a single season. Oil from the castor plant has been used for medical purposes for thousands of years: everything from hair growth to a laxative.

Castor oil is the key component in numerous industrial applications. Its water-resistance has made it a component in paint and varnish. Castor oil can maintain viscosity at extremely high temperatures so has been used as motor oil and in nylon production.

The seeds contain between 40% and 60% oil. Ricin is also present in lower concentrations. A lethal dose of ricin is considered to be four to eight seeds for a healthy adult. However, reports of actual poisoning are relatively rare, and suicides involving ingestion of castor beans are unheard of.  However, a more lethal form of ricin can be extracted from castor beans by concentrating it. Videos on line have explained how to this- a fairly uncomplicated, but time consuming process using readily available supplies and chemicals.

The likely routes of exposure are through ingestion, injection, or inhalation. A lethal does may be as little as a few grains of table salt.

If the ricin is ingested, symptoms may be delayed by up to 36 hours but commonly begin within 2 to 4 hours. These include a burning sensation in mouth and throat, abdominal pain, purging, bloody diarrhea, and seizures. Within several days there is severe dehydration, a drop in blood pressure and a decrease in urine. Unless treated, death can be expected to occur within 3 to 5 days. Antidotes are under development, but there has only been limited testing with humans. Symptoms can be treated, but long term organ damage is likely in survivors. Commercially available castor oil is not toxic to humans in normal doses

Ricin is known to have been used by injection in at least two assassinations.  In 1978, the Bulgarian dissident Georgi Markov was assassinated by Bulgarian secret police who surreptitiously injected him on a London street with a modified umbrella using compressed gas to fire a tiny pellet contaminated with ricin into his leg.  He died in a hospital a few days later; the pellet was discovered during an autopsy. Markov had defected from Bulgaria some years previously and had subsequently written books and made radio broadcasts which were highly critical of the Bulgarian communist regime

The United States restricts the possession or use of ricin since it is a potential weapon of biological terrorism. According to the 2002 Public Health Security and Bioterrorism Preparedness Act, possessing, using or transferring ricin is prohibited. There are no federal regulations restricting the possession of castor bean plants.

The recent spate of ricin letters has often been treated in the press as part of the gun culture issue. But there should be no mistake, sending a ricin letter to anyone is an act of terrorism. The federal regulation is clear. Terrorism is “the unlawful use of force or violence against persons or property to intimidate or coerce a government, the civilian population, or any segment thereof in furtherance of political or social objectives.”

Written by Gordon Massingham, the director and writer of the Emergency Film Group program “Terrorism: Biological Weapons.” Part II of the series will address sampling and decontamination issues.









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