Anyone with a good knowledge of microbiology and the right facilities can produce anthrax but experts said on October 16 that turning it into a biological weapon capable of killing millions was far more difficult.

As the number of people exposed to the potentially deadly agent in the United States climbed and fears spread around the globe, Harry Smith of the University of Birmingham said the threat should not be exaggerated and people should not panic.

At the moment after this entire furor we only have one death.

Anthrax is a favored biological weapon because its microscopic spores are hardy, easy to produce, can be ground up into a fine powder and can survive better than other pathogens.

Milling Is Most Difficult Part

All it would take would be someone who knew what they were doing, a sample of the rod-shaped bacterium and equipment found in most university laboratories.

After it is collected and fermented the resulting slurry can be either freeze-dried or placed in a centrifuge that would separate liquids and solids.

The difficult part is drying the solid material and milling it to a fine powder, capable of lodging in the lungs, without contaminating oneself or killing the anthrax spores.

"You are dealing with living organisms in a dry state and the milling would be by no means easy to produce viable organisms at the end of it," said Professor Malcolm Dando, of the University of Bradford in northern England, who has written extensively on biological warfare.

The problem is producing the material in a dry form with the right particle size with a viable organism in it and having that in a suitable form so that it would spread on the air and be breathed in the lungs.

Pulmonary anthrax is the most lethal form of the disease. Infection can also occur when the bacterium enters the skin through a cut or by consuming contaminated meat.

Very specific conditions are needed to produce the right size and characteristic particles that could be used in a biological attack to cause pulmonary anthrax.

It is an engineering problem that has been solved but all the information available suggests that this is quite a difficult process.

Biological weapon experts believe the most effective method of an anthrax attack would be to release the powder into the air and let it drift over a target area.

US experts have calculated that 100 kilograms (220 pounds) of anthrax spread over a moderately populated city on a cool, clear night could kill one to three million people.

In each case in the United States, the people were exposed to a powdered form of anthrax but because it was either in an office or through the mail it may not have been in a form effective as an airborne biological weapon.

Dando suspects that whoever is behind the US anthrax attacks was able to create a slurry and dry it but failed to perfect the milling process.

"That is my present feeling and my great hope," he said. He believes news organizations and Senate Majority Leader Tom Daschle have been targeted to maximize media attention and spread panic.

"If it is terrorism and if that is what they are trying to do, they are achieving the effect that they want," he added.

Reuters London October 16, 2001