Envelope containing ricin sent to Sen. Wicker

[link to www.foxnews.com]

An envelope containing ricin was sent to the Capitol Hill office of Sen. Roger Wicker, lawmakers told Fox News on Tuesday.

Milt Leitenberg, a University of Maryland bioterrorism expert, said ricin is a poison derived from the same bean that makes castor oil. According to a Homeland Security Department handbook, ricin is deadliest when inhaled. It is not contagious, but there is no antidote.