Friday, September 29, 2006

anthrax - still simple

* wapo: September 25, 2006; A01
FBI Is Casting A Wider Net in Anthrax Attacks

Five years after the anthrax attacks that killed five people, the FBI is now convinced that the lethal powder sent to the Senate was far less sophisticated than originally believed, widening the pool of possible suspects in a frustratingly slow investigation.

The finding, which resulted from countless scientific tests at numerous laboratories, appears to undermine the widely held belief that the attack was carried out by a government scientist or someone with access to a U.S. biodefense lab.

What was initially described as a near-military-grade biological weapon was ultimately found to have had a more ordinary pedigree, containing no additives and no signs of special processing to make the anthrax bacteria more deadly, law enforcement officials confirmed. In addition, the strain of anthrax used in the attacks has turned out to be more common than was initially believed, the officials said.
In fact, the anthrax powder used in the 2001 attacks had no additives, writes Douglas J. Beecher, a scientist in the FBI laboratory's Hazardous Materials Response Unit, in an article in the science journal Applied and Environmental Microbiology.

* Baltimore Sun: November 3, 2002
Anthrax powder from attacks could have been made simply

Single maker a possibility, scientists now theorize

By Scott Shane

The anthrax powder in the poisoned letters that killed five people last year could have been prepared using tabletop equipment costing a few thousand dollars, according to two scientists with knowledge of the FBI's yearlong investigation.

While experts consulted by the FBI believed early in the investigation that the anthrax might contain silica or other sophisticated additives to make it float more easily in the air, the consensus now is that no additives are present and that the anthrax was probably made using a relatively simple process, the scientists say.

"There's really nothing all that special about it," said one of the scientists, who spoke on the condition that they not be identified. "There are many ways to do it."
The conclusion that manufacturing the powder would not require spray-dryers costing tens of thousands of dollars or other elaborate machinery points away from the possibility that the anthrax was made by a state bioweapons program such as Iraq's. It suggests that the powder could have been prepared by a single person with the right knowledge in a relatively simple clandestine lab.

The powder in the letters addressed to Senate Majority Leader Tom Daschle and Sen. Patrick J. Leahy was made of virtually pure anthrax spores, the tough, dormant form of the Bacillus anthracis bacteria, scientists say. The powder contained about 1 trillion spores per gram, close to the theoretical limit of purity.

But one of the scientists who described the powder to The Sun said that such purity can be achieved using relatively simple methods, such as repeatedly spinning the anthrax mixture in a centrifuge and washing out non-spore materials.
Meselson said the confusion over the possibility of a silica additive may have risen because X-ray studies of the powder detected the element silicon, one component of silica. But he said silicon is naturally present in anthrax, noting a 1980 Journal of Bacteriology paper that found an "unexpectedly high concentration of silicon" in anthrax spores.

* Baltimore Sun, April 11, 2003
By Scott Shane, Sun Staff

Army scientists have reproduced the anthrax powder used in the 2001 mail attacks and concluded that it was made using simple methods, inexpensive equipment and limited expertise, according to government sources familiar with the work.

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