TOXIC WEAPONS: AS OLD AS WAR

AS A weapon, bio-chemical agents are as old as time, directed against military and civilian targets on a 2,400-year time-line, from the Spartans burning pitch and sulphur to create toxic fumes in 429BC to the 1990s nerve gas attack on the Tokyo underground.

On the eve of the first war of the 21st century, the world is awash with bio-chemical weapons categorised as bacterial, viral, biotoxic, nerve agents and cyanide.

ANTHRAX, bacterial.

Disease caused by infection of Bacillus anthracis. Organisms enter wounds, but may be inhaled. Fever and respiratory distress. Death occurs within 36 hours if untreated by penicillin, ciprofloxacin, doxycycline or special vaccine.

UK, US, Russia, Canada, Egypt, Iraq, North Korea, South Africa and Syria have supplies.

In 1979, civilians in Sverdlovsk in the USSR were infected by release of spores from a microbiological military facility.

Intentional means of release: aerosol.

CHOLERA, bacteria.

Incapacitating infection of Vibrio cholerae. Ingested from contaminated food or water. Constant diarrhoea. Death may occur from dehydration. Treated by vaccine, fluid and electrolyte replacement.

Egypt, Germany, North Korea and South Africa keep supplies. No known incidents.

Release: contamination of food and water; aerosol.

PLAGUE, bacteria.

Lethal and infectious bacterium Yersinia pestis. Bites from fleas, infected rodents and aerosol contamination. Fever, vomiting, respiratory failure. Special vaccine and antibiotics must be started within 24 hours of onset.

Canada, Egypt, Germany, Japan, North Korea and Russia. No known incidents.

Release: aerosol.

SMALLPOX, viral.

Lethal infection of variola virus. Naturally occurring smallpox has been eradicated. Fever, rigors, vomiting and skin lesions. Unvaccinated, death occurs in 30 per cent of cases.

Egypt, Japan, North Korea and Russia. No known incidents.

Release: missile.

BOTULISM, biotoxin.

Lethal illness caused by seven neurotoxins produced by bacterium Clostridium botulinum. Typically formed in canned foods and subsequently ingested.

May gain access through wounds or gastrointestinal tract. paralysis and respiratory failure. Antitoxin available.

US, Canada, Egypt, Iraq, Japan, North Korea, Russia and South Africa.

Release: aerosol or contamination.

RICIN, biotoxin.

A protein toxin which acts as a cellular poison. Produced from castor beans. Five per cent of all commercial waste from worldwide production of castor oil is ricin. Respiratory failure and circulatory collapse. No specific antitoxin exists but a protective mask may offer aerosol exposure.

US, Canada and Iraq have it.

Known to have been used in London in 1978 in assassination of Bulgarian dissident Georgi Markov.

Release: poisoning of foodstuffs or water; use of ricin-laced missiles or aerosolisation of ricin as liquid or freeze-dried powder.

TABUN, SARIN, SOMAN, GF, VX, nerve agents.

Most toxic of poisonous chemical agent cocktails. Extreme hazard in liquid and vapour states. Inhibits certain enzymes in tissues. Unconsciousness, convulsions, paralysis and halt to breathing. Death can occur in minutes.

Can be treated with atropine, pralidoxine and diazepam.

US, Egypt, France, Germany, Iran, Iraq, Libya, North Korea, Russia, Syria and Yugoslavia have the nerve agents.

Used by Iraq against Iran in 1984; Terrorist attack on Tokyo underground railway in 1995 killed 12 people and injured 5,000.

Release: missiles, rockets, bombs, spray tanks, land mines, large munitions.

MUSTARD GAS, Vesicant.

Vesicants causes vesicles - blisters - on the skin. Mustard is a chemical oily liquid and has the odour of onions or mustard - hence the name - Organs most commonly affected are eyes, skin and airways. Can cause severe bronchiolar damage and death can occur from respiratory failure.

No specific antidote. Immediate decontamination is the only way to reduce damage.

UK, US, Canada, Egypt, France, Germany, Iran, Iraq, Italy, Japan, Libya, North Korea, Vietnam, Russia and Syria have supplies.

Used extensively since First World War; In modern times by Iraq against Iran (1983); By Iraq against Kurdish freedom fighter at Halabja (1988).

Release: Missiles and munitions.

CYANIDE AGENTS

Rapidly acting poison, sometimes called blood agents.

Attacks the central nervous system and can kill within minutes. Sodium nitrate and sodium thiosuphate are effective antidotes.

Germany, Iran, Japan, North Korea, South Africa and Yugoslavia have supplies. No known use.

Release: Cyanide is in a liquid state in munitions but rapidly vaporise upon detonation.