Wednesday, April 17, 2013 CNN.com - Top Stories: Explainer: How dangerous is ricin? CNN.com - Top Stories CNN.com delivers up-to-the-minute news and information on the latest top stories, weather, entertainment, politics and more. Explainer: How dangerous is ricin? Apr 18th 2013, 00:10 Letters sent to President Obama and Miss. Sen. Roger Wicker have initially tested positive for ricin, a deadly poison. You are receiving this email because you subscribed to this feed at blogtrottr.com. If you no longer wish to receive these emails, you can unsubscribe from this feed, or manage all your subscriptions Tweet