Skip to main content
Part of complete coverage from

Ricin: Almost never deadly

By Peter Bergen, CNN National Security Analyst, and Jennifer Rowland, Special to CNN
April 19, 2013 -- Updated 1206 GMT (2006 HKT)
STORY HIGHLIGHTS
  • Since 9/11 terror attacks, eight have been arrested for attempted ricin attacks
  • Peter Bergen: Only two people succeeded in producing or obtaining ricin
  • Ricin needs to be injected or ingested to be deadly, Bergen says

Editor's note: Peter Bergen is CNN's national security analyst, the author of "Manhunt: The Ten-Year Search for bin Laden -- From 9/11 to Abbottabad" and a director at the New America Foundation. Jennifer Rowland is a program associate at the New America Foundation.

(CNN) -- In the years since the terrorist attacks of 9/11, eight people have been arrested in the United States for attempting to make the deadly poison ricin with the intent of using it for an act of politically motivated violence, according to terrorism data collected by the New America Foundation.

But only two of those individuals succeeded in actually producing or otherwise obtaining ricin, and the two ricin-dusted letters sent this week to President Barack Obama and Sen. Roger Wicker, R-Mississippi, bring the total number of attempted ricin attacks in this country since 9/11 to six.

Ricin is an attractive poison for terrorists because it can be made from the seeds of the castor oil plant, a readily available crop that is grown to produce castor oil, which is used to repel moles and voles from gardens.

Peter Bergen
Peter Bergen

Although the castor oil plant is easily accessible, extracting ricin from its seeds is a much more complex process. In 2011, Michael Crooker, a Boston-based right-wing extremist, pleaded guilty to possessing ricin and threatening a government employee. When authorities had searched his apartment seven years earlier, they found ingredients and lab equipment suitable for manufacturing ricin.

Crooker is the only known extremist to have successfully produced the toxin in the United States since the 9/11 attacks. It is not yet known how Kevin Curtis, who was arrested on Wednesday afternoon on suspicion of sending the two ricin-laden letters to Washington officials this week, was able to obtain ricin.

An effective, if rarely used, method of assassination, just a milligram of ricin, if injected or ingested, is enough to kill. In 1978, Bulgarian dissident Georgi Markov was walking across London's Waterloo Bridge when he was famously attacked by an assassin wielding a poison-tipped umbrella. The weapon inserted a small pellet containing ricin into Markov's leg. He died four days later.

Become a fan of CNNOpinion
Stay up to date on the latest opinion, analysis and conversations through social media. Join us at Facebook/CNNOpinion and follow us @CNNOpinion on Twitter. We welcome your ideas and comments.



Markov appears to be the only person to have been assassinated in a ricin attack in more than three decades. That's because to succeed, such an attack requires ricin to be directly injected, or in some other way be to directly ingested, by the victim. That makes ricin a poor choice for a terrorist trying to inflict mass casualties.

The six attempted ricin attacks since 9/11 resulted in neither death nor sickness. Most also remain unsolved cases. On October 16, 2003, someone dropped a note off at a mail-sorting office at the Greenville-Spartanburg International Airport in South Carolina.

Addressed to the Department of Transportation and attached to a small metal vial, the note read "I'm a fleet owner of a tanker company. I have access to castor pulp. If my demand is dismissed, I am capable of making Ricin." The white powder in the attached vial was soon confirmed to be the deadly substance.

Weeks later, in early November, a similar letter was discovered at a Washington mail facility that services the White House. Initial tests on an identical vial of white powder were negative for ricin, but subsequent tests at the mail facility found trace amounts of the toxin. Both letters had been signed "Fallen Angel" and demanded that the government not raise the minimum number of hours that truckers must spend at sleeper berths. "Fallen Angel" was never identified, and no personnel at either mail facility were sickened by the poison.

Three months after the "Fallen Angel" letters, ricin was also discovered on a mail-opening machine at the office of Sen. Bill Frist. Again, no one at the senator's office showed any symptoms of ricin poisoning, but the third attempted attack in a matter of months dredged up uneasy memories on Capitol Hill of the 2001 anthrax attacks, which killed five people and sickened several others.

Ricin deadly but clumsy weapon
Elvis impersonator arrested in ricin scare

Since the February 2004 incident at Frist's office, only Kevin Curtis is alleged to have used ricin in an attack. But at least six other extremists have assembled the materials necessary to produce the toxin.

Around midnight on July 8, 2005, Denys Ray Hughes was pulled over in Arizona for traffic violations. In his car, a police officer found coolers full of bomb-making materials and instructions, and Hughes identified himself as a "survivalist/militiaman," according to his criminal complaint.

During a search of his home in the ensuing investigation, police found that Hughes had cultivated thousands of castor beans from homegrown castor oil plants. He had piles of instructional material on making ricin and other poisons, but his plans for their use remained unknown.

And in 2012, four other right-wing extremists were arrested in Georgia for plotting attacks on the government and attempting to manufacture ricin. An FBI informant recorded the men discussing plans to spread the toxin across Atlanta, Washington and several other major American cities. "When it comes time to saving the Constitution, that means some people gotta die," an arrest affidavit quoted one suspect as saying.

Also last year, Theodore Shulman, a self-described "pro-choice-terrorist" was arrested and was found to have cyanide and castor beans in his possession. Shulman had threatened to injure or kidnap anti-abortion advocates, authorities said.

Documents recovered by U.S. troops from al Qaeda safe houses in Afghanistan showed that Osama bin Laden's terrorist group expressed interest in obtaining ricin. But no al Qaeda-affiliated or inspired extremist has been arrested in the United States for attempting to produce it.

Indeed, since 9/11, of the 207 indictments of al Qaeda-affiliated or inspired extremists for some kind of terrorist plot in the United States, not one of the cases involved individuals attempting to manufacture or deploy biological, chemical or radiological weapons.

Follow @CNNOpinion on Twitter.

Join us at Facebook/CNNOpinion.

ADVERTISEMENT
Part of complete coverage on
April 16, 2014 -- Updated 1201 GMT (2001 HKT)
Rick McGahey says Rep. Paul Ryan is signaling his presidential ambitions by appealing to hard core Republican values
April 16, 2014 -- Updated 1539 GMT (2339 HKT)
Paul Saffo says current Google Glasses are doomed to become eBay collectibles, but they are only the leading edge of a surge in wearable tech that will change our lives
April 15, 2014 -- Updated 1849 GMT (0249 HKT)
Kathleen Blee says the KKK and white power or neo-Nazi groups give haters the purpose and urgency to use violence.
April 16, 2014 -- Updated 1156 GMT (1956 HKT)
Sen. Sheldon Whitehouse and Rep. Henry Waxman say read deep, and you'll see the federal Keystone pipeline report spells out the pipeline is bad news
April 16, 2014 -- Updated 1153 GMT (1953 HKT)
Frida Ghitis says President Obama needs to stop making empty threats against Russia and consider other options
April 15, 2014 -- Updated 2129 GMT (0529 HKT)
Peter Bergen and David Sterman say the Kansas Jewish Center killings are part of a string of lethal violence in the U.S. that outstrips al Qaeda-influenced attacks. Why don't we pay more attention?
April 15, 2014 -- Updated 1641 GMT (0041 HKT)
Danny Cevallos says families of the passengers on Malaysian Airlines Flight 370 need legal counsel
April 14, 2014 -- Updated 1523 GMT (2323 HKT)
David Frum says Russia is on a rampage of mischief while Western leaders and Western alliances charged with keeping the peace hem and haw
April 14, 2014 -- Updated 1156 GMT (1956 HKT)
Most adults make the mistakes of hitting the snooze button and of checking emails first thing in the morning, writes Mel Robbins
April 14, 2014 -- Updated 1754 GMT (0154 HKT)
David Wheeler says as middle-class careers continue to disappear, we need a monthly cash payment to everyone
April 14, 2014 -- Updated 1155 GMT (1955 HKT)
Democrats need to show more political spine when it comes to the issue of taxes.
April 14, 2014 -- Updated 1555 GMT (2355 HKT)
Donna Brazile recalls the 50th Anniversary of the Civil Rights Act as four presidents honored the heroes of the movement and Lyndon Johnson, who signed the law
April 14, 2014 -- Updated 1317 GMT (2117 HKT)
Elmer Smith remembers Chuck Stone, the legendary journalist from Philadelphia who was known as a thorn in the side of police and an advocate for the little guy
April 13, 2014 -- Updated 1856 GMT (0256 HKT)
Al Franken says Comcast, the nation's largest cable provider, wants to acquire Time Warner Cable, the nation's second-largest cable provider. Should we be concerned?
April 11, 2014 -- Updated 1522 GMT (2322 HKT)
Philip Cook and Kristin Goss says the Pennsylvania stabbing attack, which caused grave injury -- but not death, carries a lesson on guns for policymakers
April 11, 2014 -- Updated 1906 GMT (0306 HKT)
Wikipedia lists 105 football movies, but all too many of them are forgettable, writes Mike Downey
April 11, 2014 -- Updated 1432 GMT (2232 HKT)
John Sutter and hundreds of iReporters set out to run marathons after the bombings -- and learned a lot about the culture of running
April 11, 2014 -- Updated 1649 GMT (0049 HKT)
Timothy Stanley says it was cowardly to withdraw the offer of an honorary degree to Ayaan Hirsi Ali. The university should have done its homework on her narrow views and not made the offer
April 11, 2014 -- Updated 1416 GMT (2216 HKT)
Al Awlaki
Almost three years after his death in a 2011 CIA drone strike in Yemen, Anwar al-Awlaki continues to inspire violent jihadist extremists in the U.S, writes Peter Bergen
April 12, 2014 -- Updated 0121 GMT (0921 HKT)
David Bianculli says Colbert is a smart, funny interviewer, but ditching his blowhard persona to take over the mainstream late-night role may cost him fans
April 10, 2014 -- Updated 1731 GMT (0131 HKT)
Rep. Paul Ryan says the Republican budget places its trust in the people, not in Washington
April 10, 2014 -- Updated 2128 GMT (0528 HKT)
Aaron David Miller says Obama isn't to blame for Kerry's lack of progress in resolving Mideast talks
April 14, 2014 -- Updated 1522 GMT (2322 HKT)
David Weinberger says beyond focusing on the horrors of the attack a year ago, it's worth remembering the lessons it taught about strength, the dangers of idle speculation and Boston's solidarity
April 10, 2014 -- Updated 1632 GMT (0032 HKT)
Katherine Newman says the motive for the school stabbing attack in Pennsylvania is not yet known, but research on such rampages turns up similarities in suspects and circumstances
April 11, 2014 -- Updated 1103 GMT (1903 HKT)
Simon Tisdall: Has John Kerry's recent track record left Russia's wily leader ever more convinced of U.S. weakness?
April 10, 2014 -- Updated 1640 GMT (0040 HKT)
Mel Robbins says Nate Scimio deserves credit for acting bravely in a frightening attack and shouldn't be criticized for posting a selfie afterward
April 9, 2014 -- Updated 1839 GMT (0239 HKT)
Wendy Townsend says the Rattlesnake Roundup -- where thousands of pounds of snakes are killed and tormented -- is barbaric
April 10, 2014 -- Updated 1345 GMT (2145 HKT)
Dr. Mary Mulcahy says doctors who tell their patients the truth risk getting bad ratings from them
April 9, 2014 -- Updated 1328 GMT (2128 HKT)
Peggy Drexler says the married Rep. McAllister, caught on video making out with a staffer, won't get a pass from voters who elected him as a Christian conservative with family values
April 9, 2014 -- Updated 1143 GMT (1943 HKT)
David Frum says the president has failed to react strongly to crises in Iran, Syria, Ukraine and Venezuela, encouraging others to act out
April 9, 2014 -- Updated 2057 GMT (0457 HKT)
Eric Liu says Paul Ryan gets it very wrong: The U.S.'s problem is not a culture of poverty, it is a culture of wealth that is destroying the American value linking work and reward
April 9, 2014 -- Updated 1151 GMT (1951 HKT)
Frida Ghitis writes: "We are still seeing the world mostly through men's eyes. We are still hearing it explained to us mostly by men."
April 10, 2014 -- Updated 1408 GMT (2208 HKT)
Chester Wisniewski says the Heartbleed bug shows how we're all tangled together, relying on each other for Internet security
April 9, 2014 -- Updated 1926 GMT (0326 HKT)
Danny Cevallos says an Ohio school that suspended a little kid for pointing his finger at another kid and pretending to shoot shows the growth in "zero tolerance" policies at school run amok
ADVERTISEMENT