JACKSON, Miss. — The key ingredient — castor beans — is easy to find. Crude instructions for extracting the lethal poison in them can be found on the Internet. And it doesn't require a chemistry degree or sophisticated lab equipment.
The FBI is investigating at least three cases over the past month and a half in which ricin was mailed to President Barack Obama and other public figures.
Ricin has been sent to officials sporadically over the years, but experts say that there seems to be a recent uptick and that copycat attacks — made possible by the relative ease of extracting the poison — may be the reason.
"I can absolutely promise you that when these kinds of things happen, we're going to have copycats. We expect them. We prepare for them. And we catch them," said Murray Cohen, founder of the Atlanta-based Frontline Foundation, which trains workers in how to respond to bioterrorism and epidemics.
Security and counterterrorism expert Michael Fagel, who teaches at Northwestern University and is a veteran of ricin investigations, said ricin may be employed because castor beans are so easy to come by.
The plants grow wild along highways and in other spots in the U.S. They are also considered ornamental by some gardeners and are cultivated for medicinal castor oil and other products.
"And you can go on the Internet and find out any one of a gazillion recipes on how to make ricin," Fagel said, adding that it takes only a beginner's knowledge of science to "weaponize" it.
If inhaled, ricin can cause respiratory failure, among other symptoms. If swallowed, it can shut down the liver and other organs, resulting in death. The amount of ricin that can fit on the head of a pin is said to be enough to kill an adult if properly prepared. No antidote is available, though researchers are trying to develop one.
Despite the poison's fearsome reputation, a draft of a 2010 Homeland Security Department handbook lists only one person killed by ricin, and that was a 1978 assassination in London involving injection with a ricin pellet. Someone associated with Bulgaria's secret police used a special umbrella to fire the pellet into a Bulgarian dissident.
The first of the three recent ricin investigations in the U.S. began in April. An Elvis impersonator, Kevin Curtis, was jailed and accused of sending poisoned letters to Obama, a U.S. senator and a Mississippi judge. Then Curtis was suddenly released from jail when the FBI shifted its focus to his longtime foe, James Everett Dutschke. He was charged with making ricin.
The FBI said Dutschke, a former martial arts instructor and unsuccessful candidate for various political offices, bought his castor beans on eBay and may have used a coffee grinder to turn them into a powder from recipes he downloaded on his computer.
Then in May, three poison-tainted letters were mailed from Spokane, Wash., to Obama, a federal judge and a post office. A fourth letter sent to Fairchild Air Force Base near Spokane also tested positive for the poison. The FBI is trying to locate a fifth letter it suspects was mailed to the CIA in McLean, Va.
Matthew Ryan Buquet, a 37-year-old janitor and a registered sex offender, was charged last week with mailing a threatening communication. He has pleaded not guilty.
In the most recent case, authorities say ricin-laced letters were sent to New York Mayor Michael Bloomberg and his Washington gun control group. Those letters were postmarked from Shreveport, La., but could have been mailed from Arkansas, Louisiana or Texas, officials said.
Cohen said it appears the ricin in all three cases was a crude form that's relatively easy to make. It would require laboratory equipment and scientific knowledge to make a more potent, weapons-grade version, he said.
Soon after the ricin case in Mississippi, the Congressional Research Service wrote a report for Congress that said recipes for ricin are available "on the Internet, from commercial bookstores, in patents and in scientific literature."
"The quality of these directions varies. Some directions would produce only crude preparations, while others would produce nearly pure ricin," the report said.
Thomas Pittman, a retired professor at the University of Southern Mississippi and an expert in toxicology, said ricin has a number of qualities that make it desirable to someone bent on doing harm: The ingredients are relatively easy to obtain, it's not that hard to make a crude form of it, it's deadly and it's hard to detect in a victim's body.
"It's the perfect poison," he said.
The congressional report noted some ricin cases over the years.
In 2008, authorities said a man in Las Vegas may have accidentally poisoned himself with ricin that he had made from a backyard castor plant. Roger Bergendorff told The Associated Press at the time that he made the ricin just for the sake of having it, and swore he had no intention of harming anyone. He was sentenced to more than three years in prison.
In 2003, someone sent a ricin-laced letter to the Transportation Department that was critical of new rules governing truck drivers. A similar letter was addressed to the White House the following month. Both were intercepted and nobody was hurt.
In 2004, ricin was detected in a letter sent to then-Senate Majority Leader Bill Frist's Washington office.