A Primer of Biological Weapons

Oct. 5 -- For combatants who lack the money to spend on high-tech killing instruments, biological weapons offer grisly appeal.

They are cheap, easy to make, and simple to conceal — and, since Sept. 11, on many minds. Even small amounts, if effectively deployed, could cause massive injuries and overwhelm emergency rooms.

The production of biological weapons can be carried out virtually anywhere — in simple laboratories, on a farm, even in a home.

Still, experts say it remains very difficult to transform a deadly virus or bacterium into a weapon that can be effectively dispersed. A bomb carrying a biological agent could likely destroy the germ as it explodes. Dispersing the agents with aerosols is challenging because biomaterials are often wet and can clog sprayers.

Biological weapons are defined as any infectious agent such as a bacteria or virus used intentionally to inflict harm upon others. This definition is often expanded to include biologically-derived toxins and poisons.

Types of Biological Weapons

Anthrax: The disease affects livestock, and has long been a focus of biological warfare research and development programs because it comes from relatively tough spores that can be sprayed over a battlefield or a city. Another name for anthrax is woolgatherer’s disease. Textile workers are commonly vaccinated against it.

Anthrax is most effective as a weapon when converted to a powder, which can be inhaled.

While in its first phase, anthrax is relatively easy to detect and treat. It initially causes flu-like symptoms, followed by severe chest congestion. Anthrax can then go dormant for several days. In the second phase, it is almost always fatal — vast numbers of the toxin-producing organisms accumulate in the body. Anthrax spores can live for years in carcasses buried in the ground.

Ricin: One of the most toxic naturally occurring substances known. It comes from the seeds of castor bean plants — which are also used to make castor oil. (The oil is derived from pressing the beans and keeping the ricin out.) Ricin was the poison used to kill the Bulgarian dissident Georgi Markow in London in 1978. The toxin was injected into him from the tip of an umbrella as Markow was waiting for a bus.