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W.E. Gutman: A mighty toxin from the wee castor bean

Posted: April 30, 2010 5:52 p.m.
Updated: May 2, 2010 4:55 a.m.
What evil lurks in the heart of men; what single brew is deadlier than 10?


Ricin received widespread attention in 1978, when it was determined to be the poison that killed Bulgarian dissident broadcaster Georgi Markov, then living in London. A KGB operative used an “umbrella gun” to inject a pin-sized metal sphere containing ricin into Markov’s right thigh. Markov died three days later from a catastrophic drop in blood pressure.

Another Bulgarian defector and a CIA agent were later also felled by a ricin-loaded umbrella gun. High-profile KGB defectors Oleg Kalugin and Oleg Gordievsky confirmed the KGB’s involvement in the assassinations.

Earlier, Russian dissident and Nobel Laureate writer Alexander Solzhenitsyn also suffered (but survived) ricin-like symptoms, after a 1971 encounter with KGB operatives.

The U.S. studied ricin for its military potential during World War I. The war ended before it could be weaponized. The U.S. and Canada conducted new tests during World War II, but concluded it was no cheaper than phosgene, the poison gas used by Japan during the 1937-45 Sino-Japanese War.

In 2007, a white powder found in then-Republican Senate Majority Leader Bill Frist’s office tested positive for the deadly poison, forcing closure of Senate office buildings and close scrutiny of congressional mail.

Ricin is a constituent of the seed endosperm of the castor bean plant. Although not native of the United States, it is grown commercially in California and some southern states, and used to produce industrial lubricants and laxatives. Long employed for criminal purposes, it has also been found beneficial as a cancer-fighting agent.

Ounce for ounce, ricin is one of the most toxic plant-derived compounds. It is also one of the most lethal — several times more potent than cobra venom.

One kilogram of purified ricin will kill about 4 million people. In contrast, the same quantity of cyanide will kill fewer than 20,000 people. One to three seeds would be fatal to a child. The ingestion of eight or more seeds would kill an adult. There is no known antidote.

Ricin intoxication is not immediately apparent. Early symptoms include weakness, nausea, anorexia, migraines, weight loss and fever. Death occurs by paralysis of vital centers in the brain and is characteristically preceded by convulsions, bloody diarrhea, dehydration and a sharp loss in blood pressure.

Post-mortem observations of ricin victims include hemorrhaging of the stomach and intestines, degenerative changes in the heart, liver, kidneys, pancreas, lymph nodes and spleen.

The relatively slow action of ricin does not eliminate it as a potential battlefield or terrorist weapon. (Mustard gas also exhibits a similar slow response.)

Because treatment of acute ricin poisoning is entirely symptomatic and requires crisis management, including swift removal of toxic substances from the gastrointestinal tract and enhancement of circulation with blood or plasma extenders, ricin remains a potent and terrifying poison. Its potential as a battlefield weapon, in sabotage, assassination and other terrorist operations remains undiminished. The consequences of its use can be devastating.

There is no known antidote against ricin poisoning, and the U.S. currently possesses no radical defense against it.

Despite ricin’s extreme toxicity and utility as as a biochemical warfare agent, its production is very difficult to limit. Under both the 1972 Biological Weapons Convention and the 1997 Chemical Weapons Convention, ricin has been listed as a Schedule 1 controlled substance.

This has not prevented more than 1 million tons of castor beans from being processed each year, with about 5 percent of the total rendered into a waste containing lethal concentrations of ricin toxin capable of killing thousands of people.

Ricin is several orders of magnitude less toxic than the easily weaponized Botulinium or Tetanus toxin, which are more difficult to obtain.

Biochemical warfare is as old as creation. It is nature’s gift to the weak and the vulnerable against threats, real or perceived.

Millions of years of evolution have armed legions of plants, insects, fish, reptiles, amphibians and invertebrates with the means to neutralize enemies with vile-smelling, bad-tasting, paralyzing or lethal substances. This is survival of the fittest at its Darwinian best.

Nature, however, pales in comparison with human ingenuity. Manmade potions can spread disease, foul the air and seed clouds with substances that turn rain into liquid death.

Scientists have bred mosquitoes that carry yellow fever, malaria and Dengue; raised fleas infected with bubonic plague; spawned ticks bloating with tularemia and Colorado spotted fever; and sired houseflies ready to spread cholera, anthrax and dysentery.

W. E. Gutman is a veteran journalist and the co-founder in 1986 of the now-defunct NBC (nuclear, biological, chemical) Defense and Technology magazine. His column reflects his own views and not necessarily those of The Signal.


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