Ricin as a Chemical Terrorist Agent 

What is ricin?
Ricin is a poisonous substance (toxin) found in the caster bean. Castor oil was once used as an oral laxative, but is now used mainly as an industrial lubricant and for preparing leather products. Castor beans are grown agriculturally worldwide and the plants grow wild in arid parts of the United States. Castor beans are slightly larger than pinto beans, darkly colored with light mottling, and have a small light-brown cap at one end.  The beans are not normally used as food.


How is ricin poisoning spread?
Ricin poisoning is not contagious, and is not spread from one person to another. A person must be exposed to ricin by inhalation, ingestion or injection to be poisoned.
 


Who gets ricin poisoning?
While there has been relatively little human experience with the ricin toxin, poisoning can occur following inhalation, ingestion or injection of the toxin. Ricin poisoning has occurred in suicide attempts, following accidental ingestion of castor beans, and in acts of bioterrorism and assassination. The possibility of ricin poisoning is extremely low in Pennsylvania, but at least one instance of ricin toxin manufacturing occurred in the United States in the 1990s.
 


How soon do symptoms appear?
The time from exposure to ricin toxin to onset of symptoms is usually four to eight hours.


What are the symptoms of ricin poisoning?
Eating Castor beans or ricin-contaminated material causes diarrhea, nausea, vomiting, abdominal cramps, internal bleeding, liver and kidney failure and circulatory failure. Rapid heartbeat can also occur. If the castor beans are swallowed whole, the poisoning will be less severe than if the beans are chewed. Breathing dust that contains ricin causes cough, weakness, fever, nausea, muscle aches, difficult breathing, chest pain, and cyanosis (blue skin). Breathing the dust can result in respiratory and circulatory failure. Exposure to concentrated ricin particles in the air is only likely during an act of bioterrorism where large numbers of people would likely experience the signs and symptoms in one place and time. Injection of ricin toxin would likely result in tissue (muscle) necrosis near the injection site, probable multiple organ failure, and death. All routes of exposure are very dangerous and can result in death.


How is ricin diagnosed?
Differential Diagnosis: For inhalation exposure, similar symptoms in large numbers of patients might suggest several respiratory pathogens.

Diagnostic Tests: Early post exposure (zero to 24 hours) nasal or throat swabs and induced respiratory secretions may be collected for toxin assay. Blood for serum may be collected. Toxin assays and measurement of antibody response can be performed on serum.

 

What is the treatment for ricin poisoning?
There is no cure for ricin poisoning, so only a person’s symptoms can be treated.  Acetaminophen for fever, and cough suppressants may make the patient more comfortable. Hydration is important. For those with pulmonary intoxification, respiratory support may be necessary. Pulmonary edema may need to be treated with positive end expiratory pressure ventilation and diuretics. Standard management techniques for oral poisoning should be used if the toxin is ingested.

 

What happens if ricin poisoning is not treated?
In cases of severe ricin poisoning, death can be caused by kidney failure, respiratory failure, circulatory collapse or fluid loss.

 

What method of infection control/decontamination is used for ricin?
Healthcare workers should use standard precautions. Decontaminate exposed skin by washing with soap and water and/or 0.1 percent sodium hypochlorite (1 part household bleach added to 49 parts water).

 

How can ricin poisoning be prevented?
Do not grow the Castor bean plant indoors or in areas where people may come in contact with the beans. Castor beans have been described as very attractive due to their unique mottling patterns and may be of interest to curious children. Do not eat unidentified seeds or beans. Do not drink Castor oil for medicinal purposes. If you notice any of the symptoms or signs of illness described above, seek medical help immediately.

 

Whom do I notify if I suspect a case of ricin?
Any suspect cases should be reported immediately to the local health authorities.