What Is Ricin?
Ricin is a poison that can be made from the waste left over from processing
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. For example, it is not affected much by extreme
conditions such as very hot or very cold temperatures.
Where Is Ricin Found, and How Is It Used?
- Castor beans are
processed throughout the world to make castor oil. Ricin is part of
the waste “mash” produced when castor oil is made. Amateurs can make
ricin from castor beans.
- Ricin has some
potential medical uses, such as bone marrow transplants and cancer treatment
(to kill cancer cells).
How Can People Be Exposed to Ricin?
- It would take a
deliberate act to make ricin and use it to poison people. Accidental
exposure to ricin is highly unlikely.
- People can breathe
in ricin mist or powder and be poisoned.
- Ricin can also
get into water or food and then be swallowed.
- Pellets of ricin,
or ricin dissolved in a liquid, can be injected into people’s bodies.
- Depending on the
route of exposure (such as injection), as little as 500 micrograms of
ricin could be enough to kill an adult. A 500-microgram dose of ricin
would be about the size of the head of a pin. A much greater amount
would be needed to kill people if the ricin were inhaled (breathed in)
- Ricin poisoning
is not contagious. It cannot be spread from person to person through
- In 1978, Georgi
Markov, a Bulgarian writer and journalist who was living in London,
died after he was attacked by a man with an umbrella. The umbrella had
been rigged to inject a poison 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
How Does Ricin Work?
- Ricin works by
getting inside the cells of a person’s body and preventing the cells
from making the proteins they need. Without the proteins, cells die,
and eventually the whole body can shut down and die.
- Specific effects
of ricin poisoning depend on whether ricin was inhaled, swallowed, or
What Are the Signs and Symptoms of Ricin Exposure?
Within a few hours of inhaling significant amounts of ricin, the likely
symptoms would be coughing, tightness in the chest, difficulty breathing,
nausea, and aching muscles. Within the next few hours, the body’s airways
(such as lungs) would become severely inflamed (swollen and hot), excess
fluid would build up in the lungs, breathing would become even more
difficult, and the skin might turn blue. Excess fluid in the lungs would
be diagnosed by x-ray or by listening to the chest with a stethoscope.
If someone swallows a significant amount of ricin, he or she would have
internal bleeding of the stomach and intestines that would lead to vomiting
and bloody diarrhea. Eventually, the person’s liver, spleen, and kidneys
might stop working, and the person could die.
Injection of a lethal amount of ricin at first would cause the muscles
and lymph nodes near the injection site to die. Eventually, the liver,
kidneys, and spleen would stop working, and the person would have massive
bleeding from the stomach and intestines. The person would die from
multiple organ failure.
- Death from ricin
poisoning could take place within 36 to 48 hours of exposure, whether
by injection, ingestion, or inhalation. If the person lives longer than
5 days without complications, he or she will probably not die.
How Is Ricin Poisoning Treated?
- No antidote exists
for ricin. Ricin poisoning is treated by giving the victim supportive
medical care to minimize the effects of the poisoning. The types of
supportive medical care would depend on several factors, such as the
route by which the victim was poisoned (that is, by inhalation, ingestion,
or injection). Care could include such measures as helping the victim
breathe and giving him or her intravenous fluids and medications to
How Do We Know for Sure Whether People Have Been Exposed to Ricin?
- If we suspect that
people have inhaled ricin, a possible clue would be that a large number
of people who had been close to each other suddenly developed fever,
cough, and excess fluid in their lungs. These symptoms could be followed
by severe breathing problems and possibly death.
- No widely available,
reliable test exists to confirm that a person has been exposed to ricin.
What Can People Do If They Think They May Have Been Exposed to
ricin poisoning is highly unlikely. CDC has no reports of intentional
ricin poisoning. If people think they might have been exposed to ricin,
however, they should contact the regional poison control center at 1-800-222-1222.
How Can People Get More Information About Ricin?
can contact one of the following:
- Regional poison
control center (1-800-222-1222)
- Centers for Disease
Control and Prevention Public Response Hotline (CDC)
- English (888)
- Español (888)
- TTY (866) 874-2646
- English (888)
- Agency for Toxic
Substances and Disease Registry (ATSDR) (1-888-422-8737)