10/18/2001 - Updated 02:06 PM ET Expert: 'This is not a homegrown terrorist'

By Laura Parker and Kevin Johnson, USA TODAY

WASHINGTON — The anthrax mailed to the Senate majority leader's office marks the first time such a professionally refined form of anthrax has been used as a bioterrorist weapon. "It tells me that this is not a homegrown terrorist," says Richard Spertzel, who led the United Nations' team of bioweapons inspectors in Iraq in the 1990s. "This indicates a foreign source of knowledge, at least." Federal investigators, who have had to rely on anthrax experts, doctors and microbiologists to lead them through the intricacies of bioterrorism, are not as certain as scientists like Spertzel. But the level of sophistication involved in manipulating the bacteria, investigators say, has convinced them their investigation is far more serious than it first appeared.

The key to the science is understanding the particle size.

The anthrax sent to Sen. Tom Daschle, D-S.D., in an ordinary, letter-size envelope was the product of a highly sophisticated laboratory enhancement that created perfectly sized particles.

They are small enough to hang in the air, and thus be inhaled, but large enough to stick in the nose and not be exhaled. That means the scientist who worked on the anthrax sent to Daschle's office converted the spores into their most lethal form by drying them and then manipulating the particle size to make them even more deadly.

Of the three types of anthrax disease, inhalation anthrax is the most serious. Without treatment, nine out of 10 who develop it die. A 63-year-old man in Florida died of inhalation anthrax Oct. 5, and his 73-year-old co-worker is being treated for inhalation anthrax. An exact diagnosis hasn't been made.

There are not many scientists in the world with the skill or motive to perform that kind of work, bioexperts say. But what is known about those who have the knowledge and skill helps investigators head in certain directions.

The Soviet Union achieved the highest level of sophistication in its bioweapons program and was able to genetically alter anthrax so it would be resistant to antibiotics. Spertzel and other bioweapons experts believe Iraq has the ability to enhance the bacteria's lethal qualities but has not yet ventured into genetic engineering.

The anthrax sent to the offices of a Florida tabloid publisher, to NBC headquarters in Manhattan and to Daschle's office is not resistant to antibiotics and is treatable. That's a useful clue, says Charles Duelfer, former deputy director of the U.N. inspection team and now a Washington think tank member. That, he says, suggests Iraq.

As investigators consider what the analysis on the anthrax is telling them, another key question emerges: What quantity of anthrax is being used in these attacks? Discovering that eventually could tell investigators much about its source.

A rogue scientist technically could dry a small amount of spores and mill them into finely concentrated grains in a makeshift lab. But that individual almost certainly could not pull that off on a large scale without proper equipment.

Science alone is not going to tell investigators who produced the spores and mailed them.

"Science might narrow the field, but I do not believe it will pinpoint the laboratory or a nation-state," Spertzel says. "To do that, you would have to know every possible strain in the world and which people have what strain."

Investigators say the letters sent to Daschle's office and to NBC anchor Tom Brokaw may have been sent by the same person. But the person who mailed them is not necessarily the same person who produced the anthrax spores.

Discovering the motive may be as important as the science, investigators say.

Attorney General John Ashcroft said Wednesday in an interview with PBS that the anthrax attacks could be the work of both organized terrorists and so-called lone wolves determined to engage in further disruption.

He said the same people responsible for mailing the spores to Florida, New York and Washington may also be linked to hundreds of hoaxes that have taxed law enforcement and medical authorities.

-- Anonymous, October 18, 2001