Seven Years Later: Electrons Unlocked Post-9/11 Anthrax Mail Mystery

Tuesday, September 23, 2008 - 08:28 in Physics & Chemistry

When materials scientist Joseph Michael and his team at Sandia National Laboratories in Albuquerque, N.M., trained their high-powered electron microscope on anthrax spore samples the FBI had sent them in February 2002, they made two crucial discoveries: The first confirmed previous findings that the Bacillus anthracis spores mailed to U.S. Senate offices and various media outlets (shortly after the September 11 terrorist attacks) contained silicon, a substance used to turn anthrax-causing spores into a biological weapon.But it was Sandia's next discovery that marked a critical turning point in the feds's probe of the mysterious mailings, which killed five people, injured 17 and prompted thousands more who were potentially exposed to the deadly spores to take potent antibiotics--in particular, Ciprofloxacin (known to irritate the gastrointestinal tract and cause joint swelling). Using highly sensitive transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM), the researchers came to a startling realization: The silicon had grown organically inside the Bacillus anthracis samples, nothing had been added to weaponize the spores. "The silicon was not on the outside of the spore," says Michael, who headed up Sandia's investigation, "but rather incorporated on the inside." [More]

Read the whole article on Scientific American

More from Scientific American

Latest Science Newsletter

Get the latest and most popular science news articles of the week in your Inbox! It's free!

Check out our next project, Biology.Net