• Playlist
  • Download
  • Embed
    <iframe src="http://www.npr.org/player/embed/907440/907441" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">

Traces of ricin — a deadly poison — have been found in London. And six men are under arrest, suspected of plotting to use the toxin. NPR's Richard Harris explains what ricin is and how it can be used in bio-terrorism.


Richard Harris
*NPR Science Correspondent



Please keep your community civil. All comments must follow the NPR.org Community rules and terms of use, and will be moderated prior to posting. NPR reserves the right to use the comments we receive, in whole or in part, and to use the commenter's name and location, in any medium. See also the Terms of Use, Privacy Policy and Community FAQ.

NPR thanks our sponsors

Become an NPR sponsor

Support comes from