http://www.time.com/time/magazine/article/0,9171,1101040216-588396,00.htmlAfter anthrax-tainted letters began showing up in the wake of 9/11, authorities quickly suggested that this was probably a case of homegrown terrorism rather than Round 2 of al-Qaeda's assault on the U.S. The likely perpetrator, many still believe, was a malevolent nerd with chemistry-lab expertise and a grudge against the government. But when traces of the biological toxin ricin showed up in Senator Bill Frist's mail room last week, the FBI and other agencies declared there was no evidence pointing to either a foreign culprit or a mad scientist. One possibility under examination: a good ole boy who knows his way around 18-wheelers, weigh stations and CB radios.
That would be consistent with two unsolved ricin-in-the-mail incidents that occurred last fall. They didn't create much of a panic, and despite the evacuation of three Senate office buildings last week, neither did the ricin found under a mail-opening machine on Capitol Hill. Ricin is a potent enough poison, and terrorist groups from al-Qaeda to the Iraq-based Ansar al-Islam have reportedly produced it for use as a biological weapon. So, evidently, did Saddam Hussein before the first Gulf War.
But ricin isn't especially good as a weapon of mass destruction. It's easy to make, using a recipe you can get off the Internet. It comes from the castor bean, which is used around the world in products ranging from laxatives to brake fluid to nylon, and also grows wild in the southwestern U.S., so there's no shortage of raw material. But unlike anthrax, ricin is tough to aerosolize and inhale; the easiest way to deliver a fatal dose is injection or ingestion, and you need a lot for the latter. Ricin is powerful, but it's a retail, not a wholesale, poison.
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Beyond that, investigators tell TIME that the powder found in Frist's mail room was mostly paper dust, with traces of ricin so minute, they can't even be evaluated for particle size or purity. No envelope or note has been found, and no other piece of mail from the Senate has even a trace of ricin on it. Neither do any door sills, doorknobs, railings or surfaces anywhere in the building. Same goes for air filters, which should catch floating particles.