OXFORD, Miss. —
The ricin mailed to the president and a U.S. senator is relatively easy to make but generally can't be used to target a large number of people, experts say.
A Mississippi man, Paul Kevin Curtis, 45, has been charged with mailing letters laced with the naturally occurring toxin to President Barack Obama, U.S. Sen. Roger Wicker and a Mississippi judge.
Curtis has denied making the ricin and mailing the letters.
The FBI has not yet revealed details about how the ricin was made or how lethal it may have been. It was in a powdered form inside the envelopes, but the FBI said no one has been sickened by it so far. A senate official said Thursday that the ricin was not weaponized, meaning it wasn't in a form that could easily enter the body.
More than a dozen officials, some wearing hazardous materials suits, were searching the home Friday where Curtis was arrested in Corinth, Miss. FBI spokeswoman Deborah Madden would not say if authorities have found ricin or materials used to make it in Curtis' home, and officials have not provided details about how Curtis may have either obtained or made the ricin.
Law enforcement agents should be able to test the toxin found in the letters to determine its potency and purity, as well as learn what chemicals may have been used to extract it from widely available castor beans, said Murray Cohen, the founder of the Atlanta-based Frontline Foundation, which trains workers on preparedness and response to bioterrorism and epidemics. Those chemicals might then be able to be linked to purchases made by Curtis or materials found in his home.
Curtis' ex-wife has said he likely didn't have the know-how to make ricin, and she did not know where he would buy it because he was on disability. But Cohen said ricin was once known as "the poor man's bioterrorism" because the seeds are easy to obtain and the extraction process is relatively simple.