Seriously Syria. Sarin?

A senior defence official told Associated Press that intelligence officials have detected activity around more than one of Syria’s chemical weapons sites in the last week. The defence official spoke on condition of anonymity because he was not authorised to speak publicly about intelligence matters.

This evening, AFP news agency quoted an unnamed US official who claimed the regime has already begun mixing the chemicals that can be used to make deadly sarin gas.

“We’ve picked up several indications which lead us to believe that they’re combining chemical precursors,” AFP quoted the official as saying, adding that the operation was apparently aimed at making sarin.

“I can’t comment on these reports but I have been very concerned for some time now about Syria’s stockpiles of chemical weapons and its stocks of advanced conventional weapons like shoulder-launched anti-aircraft missiles,” said House intelligence committee Chairman Mike Rogers. “We are not doing enough to prepare for the collapse of the Assad regime, and the dangerous vacuum it will create. Use of chemical weapons by the Assad regime would be an extremely serious escalation that would demand decisive action from the rest of the world,” he added.

Syria is believed to have one of the world’s largest chemical weapons programs, and the Assad regime has said it might use the weapons against external threats, though not against Syrians.

The Syrian authorities have assured Moscow that there will be no use of chemical weapons against rebel forces, Russia’s foreign minister said on Tuesday.   “I rule out the use by the [Syrian] regime of chemical weapons,” Foreign Minister Sergei Lavrov told journalists. “We have received the appropriate assurances.”

A major who defected from Assad’s embattled regime told The Times newspaper last month that the authorities would only use chemical weapons as a “last resort.”   “We discussed this as a last resort – such as if the regime lost control of an important area,” Major General Adnan Sillu said after arriving in Turkey.

According to intelligence reports on Syria’s arsenal, Damascus is believed to possess Scud-class missiles and SS-21 missiles that can carry chemical warheads, as well as sarin nerve agents and mustard agents, and may, just may, also possess VX nerve agents.

Sarin was first synthesized in 1938 by a group of German scientists researching new pesticides. Its name is derived from the names of the chemists involved in its creation: Schrader, Ambros, Rudriger, and van der Linde.

GB was the most expensive (in terms of raw materials) nerve agent selected for mass production by the Germans as part of their Grün 3 program, requiring 1058 tons of raw materials to produce 100 tons of agent.

The United States and other NATO countries would decide to make sarin their major nerve agent (later supplementing it with VX). The United States built a production plant in the North Plants complex at the Rocky Mountain Arsenal in Colorado that was capable of producing an estimated (the actual figures remain classified) 10 tons a day of the agent. Construction of the plant extended over the period 1951-1953, and GB was produced there from February, 1953 until August, 1957. The site was also used to fill weapons with GB from bulk stocks, with the last such filling operation being completed in 1969.

During its war with Iran, Iraq initiated the use of chemical weapons, beginning with sulfur mustard in 1983, progressing to tabun in 1984, and then to sarin (and eventually VX) beginning in 1987. Sarin was also used in attacks on Iraqi civilians, most notably in the March, 1988 destruction of the Halabja, where civilian deaths caused by a cocktail of different agents have been estimated at 5000.

While it is impossible to be sure about what countries have actually mass produced sarin, there is much speculation that it has been investigated by countries such as North Korea and most of the countries in the Middle East, including Israel, as indicated by the consequences of the crash, on October 4, 1992, of an El Al cargo plane in Amsterdam. Subsequently, health problems among those living near the crash site prompted an investigation, which revealed that the cargo included the sarin precursors dimethyl methylphosphanate, hydrogen fluoride, and isopropyl alcohol consigned to the Israeli CBW research facility at Nes Ziona.

On March 20, 1995, the Aum Shinrikyo doomsday cult released the nerve agent sarin in a Tokyo subway. This incident killed 11 and injured more than 5,500 people. Members of the cult left soft drink containers and lunch boxes filled with the toxin on the floor of subway trains. They punctured the containers with umbrellas just as they exited the cars. The attack was timed for rush hour, so as to affect as many people as possible. Because the sarin was of low quality and the affected cars were quickly sealed once the sarin was detected, the magnitude of the attack was suppressed. The head of the cult, Shoko Asahara, wanted more, however, and a facility, “Satyan 7,” for mass production of sarin was constructed. Satyan 7 reportedly cost $10 million to build, and an associated analytical facility is said to have cost the cult a further $1 million. The facility included computer-controlled reactors and industrial packaging equipment which automatically bagged specified amounts of the sarin and sealed the bags. The production target for the facility was two tons of sarin per day. This level of expenditure makes it clear why Tsuchiya would subsequently attempt to explain his involvement with the cult in part because Aum’s laboratories were better than those at the university where he had studied.

Julio Fuentes, a correspondent for the Spanish publication El Mundo, reported on November 19, 2001 that he had discovered at least 300 ampules (7 cm in length) containing a yellow to clear liquid packaged in boxes labeled “SARIN/V-GAS” in Cyrillic script at Farm Hada, an al Qaeda base south of Jalalabad in Afghanistan.

Like other organophosphate nerve agents, sarin inhibits the break down of the enzyme acetylcholinesterase. Under normal conditions, this enzyme hydrolyzes the neurotransmitter acetylcholine. When sarin is present, the build up of acetyl-cholinesterase results in the accumulation of excessive concentrations of acetylcholine in nerve synapses. This overstimulates parasympathetic nerves in the smooth muscle of the eyes, respiratory tract, gastrointestinal tract, sweat glands, cardiac muscles, and blood vessels.   After exposure to sarin, symptoms begin within minutes. If a person survives for a few hours after exposure, he or she will likely recover from the poisoning. The first symptoms of sarin poisoning include a runny nose, blurred vision, sweating, and muscle twitches. Longer exposures result in tightness of the chest, headache, cramps, nausea, vomiting, involuntary defecation and urination, convulsions, coma, and respiratory arrest.   Atropine acts an antidote for nerve agent, including sarin. Atropine binds to one type of acetylcholine receptor on the post-synaptic nerve. A second antidote is pralidoxime iodide (PAM), which blocks sarin from binding to any free acetyl-cholinesterase. Both should be administered as soon as possible following exposure to the toxin. Diazapam can also be used to prevent seizures and convulsions. Soldiers fighting in regions where chemical weapons are likely to be deployed are now equipped with a Mark I antidote kit containing both atropine and PAM.

One component in the U.S. binary is methylphosphonyldifluoride (Code DF; CAS Registry Number 676-99-3) and the other is either isopropanol (CAS Registry Number 67-63-0) alone or OPA, where OPA is a mixture of isopropanol 72% with isopropylamine (CAS Registry Number 75-31-0) 28%.

GB is miscible with water and readily soluble in common organic solvents. Sarin hydrolyzes readily in water, with a pH-dependent rate (half-life at pH=7 and 25° is 5.4 hours). Hydrolysis occurs more rapidly in alkaline solutions. Hydrolysis under acid conditions will produce hydrofluoric acid, and should be avoided.

SELECTED PRECURSORS

Ammonium bifluoride

Dimethyl methylphosphonate

Diethylphosphite

Dimethylphosphite

Hydrogen fluoride

Methylphosphonous difluoride

Methylphosphonyl dichloride

Methylphosphonyl difluoride

Potassium bifluoride

Potassium fluoride

Phosphorus trichloride

Sodium bifluoride

Sodium fluoride

Thionyl chloride

Trimethyl phosphite