Chemicals, bugs and deadly toxins - the new

Charles Arthur, Science Editor, on how to make the weapons, while Nicholas von

Herberstein looks at their history and lethal effect

THE NEWS that you can buy anthrax by mail order may come as a shock to many, but a decade ago two experts in the field of chemical and biological weapons noted that in the United States, "marijuana is more closely regulated ... than access to and distribution of most deadly biological cultures". And we all know how successful the "war on drugs" has been in the US.

Today, anthrax is still on sale: the American Type Culture Collection in Rockville, Maryland, offers four different kinds - shipped freeze- dried, and costing about $140 (pounds 88) for a sample. The ATCC describes its mission as "to acquire, authenticate, and maintain reference cultures, related biological materials, and associated data, and to distribute these to qualified scientists in government, industry, and education". Its catalogue contains thousands of samples of viruses, bacteria and other toxins.

However, as investigators have noted, persuading the ATCC that you are a suitably qualified scientist is "about as difficult as forging a prescription".

Considering that, and the fact that you can produce enough chlorine to kill at least one person (probably yourself) using items found under most household sinks, the question is: why do terrorists rarely choose to wage war using biological or chemical weapons?

The broad answer is that their toxicity makes them far more dangerous to manufacture and handle than a standard bomb. Few would have the confidence, or the training, of the members of the Red Army Faction, which in 1984 was discovered to be growing the bacterial botulinal toxin in a bathtub.

Intelligence experts reckon that proper growth and control of a bacterial toxin requires expertise not only in graduate-level microbiology, but also in pathology, aerosol physics and even meteorology, because not only do you have to grow your bug in a bacterial brewery (costing some thousands of pounds), you also have to know how to distribute it without killing yourself first, and without it dying in the flask - deadly microbes are often surprisingly sensitive.

Toxins and organisms such as ricin, bubonic plague and anthrax probably pose more danger to the terrorist than the target. In addition, there's always an incubation period before the effect of any attack will be seen, creating the problem of whether to claim responsibility early on (which might allow vaccination and precautions) or wait, and perhaps discover that your efforts are ignored.

By contrast, the dedicated mass-murderer might think that chemical weapons such as sarin and VX (both nerve agents) and mustard gas sound preferable. Both have clearly visible effects within minutes of exposure. But it's the manufacture and release which pose the major hurdle. Although ballpoint- pen ink and insecticides are both, according to the Canadian Security Intelligence Service, "only one chemical step away from sarin", it is a big step.

Producing nerve agents and other chemical weapons requires the manipulation of reagents such as hydrofluoric acid and organophosphates, and it's critical to get the temperatures and amounts correct, or you end up with a relatively harmless soup.

For all those reasons, only the cultish terrorist groups such as the Baader-Meinhof Group and Aum Shinri Kyo, which attracted highly educated people, have opted for such means.

Of course, for Iraq, which has a number of very intelligent and well- trained scientists, such technologies are relatively easy to obtain and fund. But the uncertainty factor, such as the problem if the wind blows chemical weapons back into your own territory, generally forestalls their use.

ANTHRAX

Symptoms: Fever, malaise, fatigue, cough and mild chest discomfort is followed by severe respiratory distress with dyspnea, diaphoresis, stridor and cyanosis. Shock and death occurs within 24 to 36 hours of severe symptoms.

History: Anthrax spores were weaponised by the US in the 1950s and 1960s before the programme was terminated. As recently as 1995 Iraq admitted to weaponising anthrax.

Treatment: It is usually not effective after symptoms are present, however the US Army medical management suggests high dose antibiotic treatment with penicillin, ciprofloxacin or doxycycline.

BUTOLINUM

Symptoms: Stomach pains, dizziness, diarrhoea, muscular weakness. The whole body including the muscles of the respiratory system become paralysed, leading to death by suffocation within days.

History: Several countries have admitted to weaponising botulinum toxins, including Iraq. In 1995 it was revealed that Iraq not only researched, but had filled and deployed more than 100 munitions with botulinum toxins.

Lethal dosage: The most lethal substance known to man. One teaspoon can kill 7 million people.

Treatment: A vaccine is available for those at high risk of exposure, but must be taken in advance. No known antidote after the symptoms appear.

SARIN

Symptoms: Runny nose, tightness of chest, dimming of visions, drooling, involuntary urination or defecation, twitching, jerking, convulsion, coma and loss of breath and death.

History: Sarin was first developed by Dr Gerhard Shrader in 1938, but mass produced by the US after the Second World War.

Treatment: Self-injection of Atropine or oxime into the thigh. Auto injectors are military only: not available to general public.

Lethal dosage: A small quantity splashed on the skin will produce enough vapours to exceed the lethal dosage (one teaspoon of sarin can kill 10,000 people).

VX

Symptoms: Runny nose, tightness of chest, dimming of visions, drooling, involuntary urination or defecation, twitching, jerking, convulsion, coma and finally cessation of breathing and death.

History: A technological improvement over the sarin gas, mass production of VX began in the United States in 1961.

Treatment: Self-injection of Atropine or oxime into the thigh. Though not available to general public, auto injectors are issued to all military forces as part of their NBC equipment.

Lethal dosage: Dermally VX is 300 times more toxic than sarin. The amount one can place on the head of a pin is sufficient to produce death in a human being.