Making Sense Of Russia's Evolving Narrative For The August 21st Sarin Attacks

Since the August 21st attack Russia has made a series of claims about the attacks that have evolved as the weeks have gone by.  The initial Russian reaction was to denounce the "biased regional media's....aggressive information attack, laying all the responsibility on the government", with Russian Foreign Ministry spokesman, Aleksandr Lukashevich claiming a "homemade rocket with a poisonous substance that has not been identified yet – one similar to the rocket used by terrorists on March 19 in Khan al-Assal - was fired early on August 21 [at Damascus suburbs] from a position occupied by the insurgents."  Clearly at odds with the UN report, which links two different types of munitions to the attacks, including a M14 140mm artillery rocket.

On August 23rd, Russian Foreign Ministry spokesman, Aleksandr Lukashevich made a new claim

More new evidence is starting to emerge that this criminal act was clearly provocative.  On the internet, in particular, reports are circulating that news of the incident carrying accusations against government troops was published several hours before the so-called attack. So, this was a pre-planned action.

This appears to have referred to multiple reports at the time that some of the videos supposedly posted on August 21st appeared with a date of August 20th, as reported by a number of sites, with those claims being republished by sites such as Russia Today, and Voice of Russia.  Below we have a screenshot from Islamic Invitation Turkey Voice of Russia used in their coverage

This obviously seemed like a very significant development, but one that hadn't been very thoroughly investigated by those making the claim.  Investigations by Storyful and others brought to attention that fact that the date displayed on YouTube videos from Syria are in fact the local time where the servers are located, in this case California, which is several hours behind Syria.  This results in videos being uploaded in the early morning in Syria being dated the day before.  It's possible to confirm the actual time a video was uploaded from metadata attached to the video, and all the videos from the August 21st attack were confirmed as being uploaded on August 21st using this data.

On August 25th the Russian foreign ministry urged against "hurried conclusions", stating

We strongly urge those who, in trying to impose their opinion on U.N. experts ahead of the results of an investigation, announce the possibility of military action against Syria, to exercise discretion and not make tragic mistakes

Following that statement Russia’s Foreign Minister, Sergey Lavrov, held a press conference, and referenced the now discredited claims about YouuTube upload times; "There is information that videos were posted on the internet hours before the purported attack, and other reasons to doubt the rebel narrative", adding "Those involved with the incident wanted to sabotage the upcoming Geneva peace talks. Maybe that was the motivation of those who created this story. The opposition obviously does not want to negotiate peacefully."  It seems the Russian foreign ministry's warning against "hurried conclusions" only went one way.

On August 29th the small independent media organisation Mint Press published a piece, Syrians In Ghouta Claim Saudi-Supplied Rebels Behind Chemical Attack, which the Russian foreign ministry would cite in a number of future statements.  The article claimed that "rebels received chemical weapons via the Saudi intelligence chief, Prince Bandar bin Sultan, and were responsible for carrying out the dealing gas attack."

The article has generated a great deal of controversy, not least for it's content.  One of the two claimed authors, Dale Gavlak, has now distanced herself from the article, claiming her contribution to the article was editing non-native speaker Yahya Ababneh's use of English, and helping Yahya pitch it to Mint Press.  She claims she clearly told Mint Press "this should go under Yahya Ababneh's byline. I helped him write up his story but he should get all the credit for this."  As her reputation was used to give the article by the virtually unknown Ababneh credibility, this controversy has brought the content of the article into doubt.

As for the article itself, the claims of rebel involvement in the August 21st attack actually seems quite thin.  There's talk of an accident in tunnels releasing chemicals, killing a number of rebels in the area, but it doesn't claim this event and the August 21st attack are linked. In fact, only the headline (which Dale Gavlak told me was written by Mint Press) and this section makes any reference to the August 21st attack

However, from numerous interviews with doctors, Ghouta residents, rebel fighters and their families, a different picture emerges. Many believe that certain rebels received chemical weapons via the Saudi intelligence chief, Prince Bandar bin Sultan, and were responsible for carrying out the dealing gas attack.

Beyond the headline and that one paragraph, there's no further claims that the rebels were responsible for the August 21st attack, and certainly none of the quotes from locals link the rebels to the August 21st attack.  This didn't stop it becoming part of Russia's ongoing attempts to blame the opposition for the August 21st attack.

On September 16th Russia’s Foreign Minister, Sergey Lavrov, came out with more claims about the August 21st attack, dropping the earlier claims of YouTube videos being uploaded before the attack took place.

There is lots of evidence delivered by independent experts onsite [a nun from a local convent, other eyewitnesses and Western reporters] and European and U.S. experts, including twelve retired officers of the Pentagon and the CIA who sent an open letter to President Barack Obama to explain how the case had been falsified, unfortunately, a lot had been done before the St. Petersburg meeting by bad people who used poisonous chemical substances largely, in our opinion, to provoke a retaliation strike against the regime and shifted the responsibility for the use of chemical weapons, although that was totally illogical and Russian President Vladimir Putin said so many times.

Putting aside claims about nuns and retired Pentagon and CIA officers for now, you'll note he mentions "other eyewitnesses and Western reporters" as "independent experts onsite".  In a later comments made on September 22nd he's reported as saying

Evidence given by witnesses and journalists showed that rebels acquired “some shells from abroad that they had never seen and had no idea of how to use them, and then finally they used them,” Lavrov said. 

Claims he repeated in a September 25th interview with the Washington Post

Russia is still saying that it was the rebels who fired the chemical weapons on Aug. 21 — not the Assad regime?Yes, we believe there is very good evidence to substantiate this.

Are you willing to present this evidence?Yes, I just presented a compilation of evidence to John Kerry when we met a couple of hours ago. This evidence is not something revolutionary. It’s available on the Internet. They are reports by journalists who visited the sites and talked to the combatants, who said they were given some unusual rockets and ammunition by some foreign country and they didn’t know how to use them. There is also evidence from the nuns living in the monastery nearby who visited the site. You can read the assessments by the chemical weapons experts who say that the images shown do not correspond to a real situation if chemical weapons were used. And we also know about the open letter sent to President Obama by former operatives of the CIA saying the assertion that the [Syrian] government used chemical weapons was fake. So you don’t need to have any spy reports to make your own conclusions, you only need to carefully watch what is available in public.

As far as I'm aware, apart from the Yahya Ababneh's Mint Press article, there's no other journalists who have claimed to have visited the site, and recounted the story of  combatants who were "given some unusual rockets and ammunition by some foreign country and they didn’t know how to use them.".  It seems clear Lavrov has repeatedly referred to the Mint Press article, which has become increasingly controversial by the day.

Lavrov and the Russian foreign ministry also repeatedly refers to "nuns living in the monastery nearby who visited the site".  This seems to refer to the controversial nun, who has made a number of statements in the past supporting the Syrian government, including claiming the Syrian opposition were responsible for the notorious Houla massacre, and has been described as

According to the Swiss newspaper Le Courrier, Agnès-Mariam was “comfortable among [Assad’s] security services,” and she told their reporter it was hoped he could “dismantle the propaganda of Western media.” 

On September 6th she was interviewed by Russia Today ('Footage of chemical attack in Syria is fraud'), and made a number of claims about the attack, which were later repeated in a 50 page report her organisation prepared.  According to a BBC report on her work, her report asked

• Ghouta, the main area to the east of Damascus which came under attack, was already "deserted", so why were there were so many civilian casualties?
• Why are so many children seen in the videos without their parents? There is "a flagrant lack of real families"
• Why are there so few women in the videos and why are so many people unidentified?
• Why is there so little evidence of burials?

In response, Peter Bouckaert, emergencies director of Human Rights Watch, stated "There's just no basis for the claims advanced by Mother Agnes.  She is not a professional video forensic analyst... we have found no evidence to indicate any of the videos were fabricated.".  In addition to that, he addressed the questions raised by her report

• There were tens of thousands of civilians trapped in the Ghouta area of Damascus, according to very regular reports received by Human Rights Watch
• Children were often sleeping in the basements of buildings in significant concentrations because of the intense shelling and that is why so many died (Sarin gas accumulates at low levels)
• The dead and those injured in the chemical attack were moved from place to place and room to room both at the clinics and ultimately for burial
• There were many men and women who were victims of the attacks. But there were separate rooms for the bodies of children, men and women so they could be washed for burial
• Almost all of the victims have been buried
• Human rights researchers have spoken to the relatives of Alawite women and children abducted by rebels. None of them said they had recognised their loved ones in the gas attack videos

There's also the third major claim Lavrov was pushing, that former CIA and Pentagon officers "saying the assertion that the [Syrian] government used chemical weapons was fake".  Michael Kelley of Business Insider looked at this claim, stating

Lavrov then cited an open letter sent to President Obama by former operatives of the CIA that cites the Mint Press report and states that they are "unaware of any reliable evidence that a Syrian military rocket capable of carrying a chemical agent was fired into the area." 

The UN chemical inspectors investigation described the size and structure of two rocket delivery systems used and report the direction some of the rockets likely came from. The report doesn't ascribe blame but present evidence that is damning for Assad.

In addition to these claims, on October 1st, Lavrov, referring to an earlier chemical attack in Khan al-Assal the Russians have blamed on the opposition, stated

We have no doubt that sarin gas – which was used on March 19 in Aleppo, is home-made… We also have information to corroborate that in the course of the tragic events of August 21, when chemical weapons were used, sarin gas of a very similar chemical signature to the one on March 19, was used, but of a much higher concentration 

Again, a Khan al-Assal link, but instead of claiming the same type of rocket was used in both attack (which the UN report seems to have disproven), Lavrov is now claiming it was Sarin with a very similar chemical signature.  Not only that, it's home-made Sarin, and following the logic of his earlier claims, this is home-made Sarin made by the Saudi's and provided to the Syrian opposition in Damascus, and therefore must have also been provided to the opposition for the Khan al-Assal attacks.  If true, this would implicate the Saudi's in not only the August 21st attack, but also the earlier Khan al-Assal attack, which would obviously be huge.  On October 4th Interfax reported

A group sent by Saudi Arabia from Jordanian territory is responsible for the August 21 chemical weapons provocation that was staged in the Eastern Ghouta suburb of Damascus, Russian diplomatic sources told Interfax. 

"Having analyzed this information, which was received from a whole range of sources, we are getting the picture confirming that the criminal provocation in Eastern Ghouta was committed by a specialized group that was sent by Saudi Arabia from the territory of Jordan and acted under the cover of the Liwa al-Islam group," one of the sources said.

So now we have a "specialised group" acting under the cover of "Liwa al-Islam" staging "criminal provocation", who traveled to Eastern Ghouta via Jordan.  It's unclear if they brought the barrels of home-made Sarin with them, or they were already there when they arrived.  Despite the claimed linked between the Sarin used in the Khan al-Assal attack and the Eastern Ghouta attack, according to Russia it must have been two different groups responsible, because when they submitted their report on the Khan al-Assal attack to the UN, they stated

It was determined that on March 19 the rebels fired an unguided missile Bashair-3 at the town of Khan al-Assal, which has been under government control. The results of the analysis clearly show that the shell used in Khan al-Assal was not factory made and that it contained sarin

And that

According to Moscow, the manufacture of the ‘Bashair-3’ warheads started in February, and is the work of Bashair al-Nasr, a brigade with close ties to the Free Syrian Army. 

So does this mean the home-made Sarin provided by Saudi Arabic supposedly used in both attacks was in one instance provided to Bashair al-Nasr, while in the Eastern Ghouta attack it was a team of special agents under the guise of Liwa al-Islam who deployed it? Maybe the Khan al-Assal attack was executed by a team of special agents pretending to be Bashair al-Nasr?

Or maybe, as Russia's attempts to blame the opposition for the August 21st attack get more convoluted, they make less and less sense.

You can contact the author on Twitter @brown_moses or by email at brownmoses@gmail.com.

Chemical Weapon Specialists Talk Sarin, Saraqeb, and Khan Al-Assal - Part 2

Here's the second set of answers from two more chemical weapons specialists on the use of chemical weapons in Syria.  Part one can be found here.

Dan Kaszeta, a US Army Chemical Corps veteran, provides some very detailed answers on sarin.

What form does sarin take?  

Sarin (also know as GB) is a liquid at normal temperatures.  It has the appearance and general consistency of water. The term “sarin gas” is misleading.  It is not a gas at normal temperatures. (For example, chlorine is a gas at room temperature.)  It is liquid between the temperatures of -56º C and approximately +150º C, although it evaporates in proportion to the temperature.

Sarin has a viscosity (how thick the liquid is) slightly higher than water, although my own experience is that you can’t tell with the naked eye.  

Vapour pressure. Sarin has a vapour pressure.  In other words, it has a tendency to evaporate into a vapour state from liquid state, just like many liquids.  Water, alcohol, petrol, acetone, etc. all have vapour pressure.   Sarin has a slightly lower vapour pressure than water.  This means (all other factors being equal) that a drop of Sarin at 25º C should evaporate slightly slower than a drop of water.  In practice, it often evaporates quicker than water.  I’ve seen a drop of water next to a drop of Sarin on the side of a rifle in a test chamber. This is because there is already water vapour in the air (i.e. humidity).  So, the rule of thumb that I learned is that Sarin evaporates like water in the desert.  

It should be noted that at high temperatures, Sarin evaporates very quickly.  This makes it a “non-persistent” nerve agent.   At room temperature or higher, terrain, clothing, equipment, etc. will not remain contaminated for long periods of time as any liquid droplets will evaporate.  This is in contrast to so-called “persistent agents” (e.g. GD, VX) which have lower vapour pressures and evaporate much slower. 

Sarin vapour is heavier than air.  

Can it be liquid, gas, powder, etc? 

The best way to describe Sarin is that it is a liquid that gives off vapours.  It should be noted that many ways of dispensing Sarin (see weaponisation below) cause the formation of an aerosol – a finely divided cloud of droplets.  Aerosols behave much like gases and vapours.   

“Dusty agents”/ Powder: There’s no way that I know of to dispense Sarin as a solid or powder, although I can’t completely rule out the possibility that someone has developed a “dusty agent” form of Sarin.  There is some literature out there on the possibility of “dusty” chemical warfare agents.  As far as I know, this was only ever a possibility with really low vapour pressure agents, not fast evaporating agents like Sarin. The only benefit I can think of for making a “dusty sarin” (in reality, not Sarin as a powder, but small particles impregnated with sarin) would be to slow down the evaporation time of the Sarin… i.e. increase its persistency.   But doing so would decrease the rate at which the agent is dispensed in vapour form, thus reducing its immediate lethality somewhat.  And immediate lethality is the point and purpose of Sarin.   It would seem to have little utility and an awfully difficult way of engineering some persistency into Sarin.  It would be far easier to use a more persistent nerve agent instead.  Or it may be possible to thicken Sarin with an additive. The US government applied for a patent to do so in 1969.

Does it have a particular smell or colour?

It is colourless.  Pure sarin has no odour.  Even if it did have an odour, it would be difficult to tell as a concentration detectable by a human nose is probably a lethal exposure.  

How is sarin typically weaponised?

By “weaponised” we generally mean “how is this chemical put into a device or munition in order to function effectively on the battlefield. In order to answer this question we must apply the characteristics of the liquid Sarin to the battlefield environment.  Because of its physical and toxicological characteristics, the most useful methods of employment for Sarin or any other non-persistent nerve agent are means and devices that rapidly disperse droplets or aerosols in a concentration high enough to cause immediate casualties. Dispersing a payload of Sarin in one load of liquid all in one place (like dumping a bucket) causes a great hazard in one spot, but not wide effects.  A device that did this would be less useful than a conventional explosive device of similar size.  Likewise, dividing it too finely over a large area will cause it to disperse quickly and not have a concentration adequate to cause incapacitation or death.  Again, such a device would have little or no value in comparison to a conventional device of similar size, weight, or shape.   

The overall guiding principle for weapon design with Sarin was that is was meant to rapidly cause casualties, and as such, weapons/munitions were designed to detonate/disperse at ground level.  (As opposed to persistent agents, which are designed to contaminate terrain and equipment, which generally burst/dispense/detonate some meters above ground level in order to spread a radius of droplets.) During the Cold War, the various superpowers devoted a lot of time, expertise, and money to studying and testing various weapon designs to see how effective different munitions and configurations might be.  Rather a lot of this information is now out in the public domain, either directly in form of declassified documents or indirectly, e.g. we can see the types of weapons that were the result of testing and optimisation and draw our own conclusions as to what types of weapons work and which ones don’t.  Drawing on US and Soviet experience, the following are the classic weapons for dispensing Sarin on the battlefield, all fuzed to detonate at surface:

• Artillery shells 
• Mortar shells 
• Air dropped bombs 
• Cluster bombs
• Missile warhead
• Rocket warhead
• Land mine

It should be noted that some types of weapons that aren’t so good for Sarin:

• Hand grenade – Very small payload possible.  Possibiity of leakage killing soldier handling it.  Soldier likely to have to be in protective gear the whole time.  Soldiers throwing grenades in protective gear are probably going to be less accurate and achieve less distance.
• Grenade launcher round – same liabilities as hand grenade.  And very low payload.
• Aerial spray devices – Unless the helicopter or aircraft is almost at ground level (highly unlikely), the Sarin would be too dispersed to have much effect.  Aerial spray devices are better for more viscous persistent agents (like Mustard or VX)
• Anything fuzed for aerial burst.  Likely to spread the droplets 
• Any explosive dissemination device with too little or  much explosive.  I won’t specify what it is (for obvious reasons) but there is an optimum ratio of charge to agent.  Too little leaves a puddle, too much spreads it too thin.

Some notes about types of “agent fills”.  An “agent fill” is a term that describes exactly how the chemical warfare agent is configured inside.  There’s three basic kinds of agent fills:

• Unitary: This means the agent is in the weapon in one big pool.  
• Binary:  Binary fills mean that two separate components are mixed to created the chemical agent.  Generally, this is done for the purposes of safely handling the munitions and to avoid having to store chemical weapons or filled munitions.  Sarin could be mixed on-site and poured into empty shells/rounds or munitions could be designed to mix two different components in flight.  To my knowledge, this was done with GB and VX.  A well-made binary weapon would have little or no difference from a unitary fill.  A poorly made one would have a high dud rate and would be generally less effective.
• Submuntions: A highly effective way of dissemination would be a munition that scattered bomblets or submunitions at some height, with the submunitions designed for ground impact detonation.  Other factors being equal (…but they often aren’t), submunitions are generally considered a more efficient method of dispensing Sarin.  

A note about “dud rates.”  Any class of munition has a dud rate, i.e. the percentage of shells/rockets/etc. that fail to function as intended.  Anecdotal evidence is that some older chemical weapons may have quite high dud rates. Even many modern conventional artillery rounds have non-trivial dud ratesv there’s no physical mechanism to explain why chemical rounds would have a radically lower dud rate.  This means that if any significant use of chemical warfare happens, there’s going to be an unexploded shell out there somewhere, which will be of great intelligence value if it can be safely retrieved.  (A task not for amateurs!)

Have you ever heard of sarin being used in a diluted form, or mixed with other chemical substances to make it less lethal?

There seems to be little point in trying to dilute Sarin to have some kind of non-lethal effect and I have no knowledge of this ever happening.  The sub-acute, low-level signs and symptoms of nerve agent poisoning are annoying but not terribly debilitating.  Giving a bunch of people a runny noses and pin-point pupils has far less tactical usefulness than using conventional riot control agents or the generally non-lethal vomiting agent adamsite. Such agents can easily cause debilitating effects, whereas with nerve agents, there’s a fine razor’s edge, not easily (or at all) controllable between incapacitating dosage and lethal dosage.  Why risk the opprobrium of the international community and the possibility of triggering international intervention by using just a wee bit of Sarin?  There seems no point. 

Sarin is designed to injure and kill.  There’s not much leeway between the incapacitating doses and lethal doses with Sarin (1000 mg and 1700 mg respectively as the ED50 and LD50) and the concentration that would lead to a person absorbing 1000mg Sarin would quickly lead to absorption of a lethal dose of 1700mg. 

A number of reports have claimed to have proven the use of sarin through tests on hair, clothing, blood, tissue, and urine samples.

I will address each of these types of samples in turn:

Blood: 

Sarin can be directly and indirectly detected in blood samples.  Several methods have been studied for detection of sarin in blood. Several studies have been described in the academic literature. There are also indirect methods that detect decomposition products of sarin or the physiological effects of sarin. 

Experience from the Tokyo subway incident in 1995, documented by the OPCW shows that one of the decomposition products of Sarin is a chemical known as IMPA is detectable in blood.   

Sarin’s method of action is to inhibit a substance called acetylcholinesterase, which is used by the human nervous system.  At least one study shows that the presence of a nerve agent could be deduced by examining post-mortem blood samples for presence or lack of acetylcholinesterase, up to a week after death.  A person who has died from Sarin exposure would have little or no acetylcholinesterase present.  It should be noted that this would only indicate the presence of a nerve agent and would not specifically indicate Sarin versus any other nerve agent (or even organophosphate pesticide intoxication) nor would it conclusively indicate nerve agent as a cause of death, as other factors may have killed the victim, such as conventional trauma. 

Urine

One of the decomposition products of Sarin in the human body is methylphosphonic acid.  A study shows that this substance is detectable in urine by use of mass spectrometry.   This particular substance is not specific to Sarin.  (The journal article says it is a decomposition product of cyclosarin, Soman and one type of VX as well.)  It should be noted that it can take some time for chemicals absorbed in the human body to end up in urine.  An immediate post-exposure sample may not have any evidence of exposure.

Tissue

A study from 2004 using guinea pigs indicates that plasma, heart, liver, kidney, and lung samples can indicate the presence of either Sarin or Soman using gas chromatography and mass spectrometry.  

Clothing, Skin, or Hair

Clothing, skin, or hair could get contaminated by droplets of Sarin.  I cannot find any literature on the absorption of Sarin into human hair, but common sense would dictate that any water-like liquid could be trapped in hair.  Because of the rapid speed at which Sarin evaporates, a sample would need to be collected quickly and kept in a sealed container.  A lowered temperature would help.  In such a case, the Sarin might actually be most easily identified in vapour form in the headspace of the container, having desorbed from the sample itself. 

How would these samples be tested for the presence of sarin?

First of all, my expertise is not very strong in the laboratory techniques used for such analysis.  My expertise is strongest in field detection techniques.  To the best of my knowledge, the generally accepted gold-standard analytical technique is the combination of gas chromatography and mass spectrometry (GC/MS) which is widely used by chemists to identify molecules.  GC/MS is a sophisticated technique requiring training and expensive equipment mostly found in labs.  There are some portable GC/MS devices, but they are generally used in vehicles or mobile labs and aren’t handheld devices.  

The following are field technologies which also have relevance in laboratory settings, given the appropriate equipment. All have pros and cons.

• FTIR:  Fourier transform infrared – Used to analyze a gas, vapour, liquid, or solid sample.  Not real time. An identifier, not a surveillance or detection tool.
• Raman: Laser-based identification technique that can identify liquids or solids. Not real time. An identifier, not a surveillance or detection tool.
• Ion Mobility Spectrometry (IMS):  Fast acting analysis of gas and vapour. IMS is the backbone of military field electronic nerve agent detectors. Works very quickly and is very sensitive.  Some problems with false positives, varying from model to model.  Some units will only detect, others will identify as well (i.e. discriminate VX from Sarin), while others provide a qualitative (“Hi, Med, Low”) or quantitative (“25 mg/m3”) measurement.
• Flame ionization: Used by a family of French chemical warfare detectors.  Broadly similar to IMS in application
• Photoionization: Commonly used in civilian HAZMAT detectors.  Generically detects toxic gases, but cannot identify chemicals.  Would not be able to tell difference between, say, ammonia, acetone, and Sarin.  I only mention this because it is so prevalent in civilian fire departments. 
• Wet chemistry: A variety of manual chemistry techniques ranging from very sophisticated to very simple.  Too many different kits and tools to generalize, other than to state that the cheap tools are easy to use but not very specific, whereas the expensive tools can be good but hard to use.  There are some specific nerve agent detection techniques in this category, but they generally have difficulty discriminating between types of nerve agent.  

If sarin was detected in hair and urine wouldn't that suggest small, non-lethal quantities, being ingested over a period of time?  

Sarin detected in hair might theoretically be a small droplet that was in the hair as a direct result of a Sarin attack.  However, the sample would have to have been collected quickly and sealed up.  (See above)  I don’t know of a biological mechanism that would result in Sarin or byproducts ending up inside human hair through hair growth.  I checked the literature and found nothing in this regard.  

As far as urine is concerned, I can’t find direct literature in my cursory search about how quickly Sarin or decomposition products end up in urine.  However, Sarin acts on the bladder and kidneys rather quickly, so this cannot be ruled out.  One Japanese Sarin victim of the lesser-publicized Matsumoto incident (previous to the infamous Tokyo incident) had measurable Sarin decomposition products in his urine. 

If sarin was on clothing how hazardous would it be to handle that clothing without correct protection?

Very hazardous.  Depending on the amount of contamination, possibly lethal. Full head-to-toe protection would be needed.  The fastest acting hazard would be vapour from the clothing.  

Is it possible other substances could produce false positives for sarin?

Yes.  Generally, the more sophisticated and expensive the detection technique, the less scope for false positives.   The false positives depend entirely on the detection method.  IMS is often fooled by chemicals of the same molecular weight as sarin.  Organophosphate-based pesticides are very similar chemicals to nerve agent chemical weapons, so they may pose a false positive. 

After a suspected sarin attack how should the victims be processed, and what precautions should be taken?

An effort should be made to triage the victims and deal with the most severely affected ones first.  Triage guidelines are available in various resources. The general acronym ABCDD can be used to describe the field medical interventions required for nerve agent exposure.  This stands for Airway, Breathing, Circulation, Drugs, and Decontamination.  A general broad guideline for dealing with a serious sarin casualty is as follows:

• Move casualty out of danger.  If possible remove contaminated clothing
• Establish and maintain airway, through intubation if necessary
• Control secretions through suction
• Ventilate with oxygen if available, using bag-valve mask if necessary.  Regular air is better than nothing if oxygen is not available. 
• Monitor pulse, commence compressions if pulse stops
• Administer atropine, pralidoxmine (or other oxime, in accordance with local protocols), and diazepam via intramuscular injection.  
• Decontaminate any possible skin exposure.  Soap and water are fine, if specialty decontaminants are not available. Even plain water will work in a pinch. Flush eyes with water. 
• Establish IV access to allow further antidote administration
• Administer additional antidotes as required
• Move to definitive care
• Constantly reassess airway, breathing, and circulation en route. 

If these precautions are not taken what is likely to happen to the people coming in contact with the victims?

If the victim was only exposed to Sarin in vapour form, which is quite possible, then there’s no particular hazard.  If a victim has been exposed to droplets or liquid, then persons coming into contact with the victim are likely to be affected if they are unprotected.  Due to the rapid rate at which Sarin evaporates, the principle hazard will be respiratory hazard, although contact hazard risk cannot be eliminated.  Droplets on skin, hair, and clothing are likely to evaporate and pose a respiratory hazard both to the victim and bystanders/helpers.  

How long would it take sarin to become harmless, or dissipate?  In general terms are we talking minutes, hours, weeks? 

Minutes to hours, depending on wind and air temperature and the volume of liquid sarin.  Sarin liquid evaporates quickly.  Vapour will disperse quickly in the open, but could last a very long time in a combined space. 

Steve Johnson is Lead for Explosive and Hazardous Forensics at Cranfield university

Sarin

How is sarin typically weaponised?

Militaries have used a wide range of techniques. Artillery shells, missiles and rockets are probably the most commone, although drop/spray tanks and even jet engines (Russia) have been tried. In Tokyo it had been intended initially to aerosolise but ended up being stabbed bags left to evaporate (which is pretty good due to the speed at which it evaporates).

What form does sarin take?  Can it be liquid, gas, powder, etc? Does it have a particular smell or colour?

Its normal state is liquid, although it steadily evaporates at a similar rate to water. Its Boiling point is 158 degrees C, Freezing point is -56.

It’s unlikely to be a gas although it may be produced as an aerosol from a mechanism. It would not be a powder unless it was absorbed on to a powder or solid in order to produce one.

Have you ever heard of sarin being used in a diluted form, or mixed with other chemical substances to make it less lethal?

Not to make it less lethal – Binary production of sarin from separate less lethal and often more stable chemicals is practical and has been done in the past. The Tokyo attacks often refer to dilute sarin but that was unlikely to have been to make it less lethal.

A number of reports have claimed to have proven the use of sarin through tests on hair, clothing, blood, tissue, and urine samples.  How would these be tested for the presence of sarin?

The metabolic uptake of Sarin and its behaviour within the body is relatively well studied. For tissue samples there are a number of markers that investigators can look for and there efficacy is dependent on the time after exposure and the route of introduction (inhalation will get it in to blood fast, presence in urine is often many hours after exposure). Markers that can be looked for are:

• Sarin – unreacted pure sarin.
• Acetylcholinesterase(AChE and Acetylcholine – This only gives an indication that the nervouse system has been disrupted , potentially, but not exclusively by a nerve agent or substance behaving like one.
• isopropyl methtylphosphonic acid (IMPA) – a breaking down of Sarin, sometimes called the hydrolysis product. Pretty good and a number of studies have looked at its detection in blood and urine of Tokyo victims. Fairly hard to think of reasons for it to be in blood other than exposure to sarin.
• methyl phosphonic acid. A further breakdown product but with more potential causes.
• Macro molecules from other Sarin/protein interactions (Phosphylated tyrosine). Not impossible and potentially good for investigation longer after the exposure point.
• Butyrylcholinesterase.  While AChE is found more in the red blood cells BuChE is found more in the serum of blood. It is less affected by Sarin, but in the event of a high exposure you would expect to see it affected as well and this can be a good ratio to examine when trying to assess exposure history with samples that have a poor patient history (much like we currently have).

Different markers fall away at different times after exposure. IMPA tend tobreakdown to MPA. Ache levels return to normal after about 30 days.  BuChE around 50 days.

If sarin was detected in hair and urine wouldn't that suggest small, non-lethal quantities, being ingested over a period of time?  

Potentially. Or a small single dose. Again working up a full spectrum of the biomarkers should be able to help understand that.

If sarin was on clothing how hazardous would it be to handle that clothing without correct protection?

It’d be pretty stupid but if it were pure(ish) sarin then it evaporates at about the same speed as water. So in many cases the levels left could be very low.  Some countries are fairly casual about contamination of items that have been in the vicinity of sarin because they don’t believe the vapour condenses on surfaces easily – i.e. being near some sarin won’t contaminate you or clothing  unless you touch it. That’s not necessarily a universally accepted fact though.

Is it possible other substances could produce false positives for sarin?

In the medical tests – yes as discussed a little above. IMPA and Phosphorylated tyrosine are pretty good though. In any event though they would still be indicating a significant chemical injury to the person from a pesticide perhaps. That’s why it is so important to have a context and medical history of the person from whom the samples are taken in order to make a diagnosis. It is a fact of modern medicine that a large amount of diagnosis is based on symptoms and context/case history – which is one of the reasons people are so twisted about these samples. They need context no matter how good the test.

After a suspected sarin attack how should the victims be processed, and what precautions should be taken?

I actually think PHR have a very good fact sheet on this.

If these precautions are not taken what is likely to happen to the people coming in contact with the victims?

It really depends on the amounts of agent and how the people were exposed. You could treat sarin victims with no protection and be ok, perversely those exposed to CS will (and there is a lot of evidence of this in civil cases) present a very high hazard to medical staff due the the difficulty in decontaminating riot control agents.

How long would it take sarin to become harmless, or dissipate?  In general terms are we talking minutes, hours, weeks?

Minutes in Syria during the day.

Saraqeb

The Saraqeb attack is probably one of the mostly well documented alleged chemical weapon attacks of the conflict.  Canisters inside containers filled with white-grey powder were reportedly dropped from a helicopter, landing in two locations, one near a road, where no victims were reported, and the other in the courtyard of a family home.  It was reported that immediately after impact, one of the residents entered the courtyard, and collapsed shortly afterwards, later dying.
Shortly after the first victim entered the courtyard more members of the family entered, and also fell ill, as did people responding to the attack.  Between 11 to 13 people were reportedly effected, with only one death reported.  Video from the road-side location filmed some time after the attack would show children playing near to the remaining white-grey powder with no ill effects reported. (A more detailed breakdown can be found here)

Would the above scenario match what you'd expect to see if Sarin has been used in the attack?

Not really. The powder is unusual and the death rate is very low. It’s certainly not what one would normally expect.

In common with many alleged chemical attacks in Syria the medical staff appears to have no protective gear.  If this was a sarin attack, how likely would it be that the medical staff would be effected, and how long would it take for the medical staff to become effected?

This depends on if the patients are externally contaminated. They may just have inhaled it. Speed of action on medical staff if they were contaminated would depend on the level. If very low there may be no real noticeable effects given the general alarum in a casualty receiving post. If significant then within minutes. In fairness though the fact there is a patient and not a corpse would suggest that the level of contamination is low or the agent is non-lethal. As death from Sarin is pretty rapid.

One video shows a car pulling up with at least one victim inside.  If this was a sarin attack, how likely would it be that the inside of the vehicle would be contaminated by sarin?  If the victim inside the vehicle had been exposed to sarin is it likely other passengers in the vehicle would fall ill?

Syrian vehicles are far from airtight. If the victim had inhaled then there is no real reason for the car to become very contaminated. Potentially the victim migh exhale some contamination (this certainly happens with cyanide suicide).

Some people have proposed a scenario where a diluted mixture of sarin and other substances was used in the attack.  If that was the case, would your answers to the above questions change significantly?

Not really other than it might be possible to create a powder with another substance.

The canisters recovered from the scene of the attacks matched canisters also recovered from an attack reported in Sheikh Maqsoud in Aleppo, where there were again claims of them being dropped from a helicopter, with photographs showing the canister remains covered in white-grey powder.  

The same design of canister has also been filmed in a cache of weapons reportedly captured by the Syrian opposition from the Syrian military, and a journalist in Syria has shown the image of the canister to various armed group, many of which have claimed to have seen them in the possession of opposition fighters, claiming to have captured them from the Syrian army.

Another type of grenade, using an identical fuze, was also photographed in Syria, with the photographer being told it was a normal smoke grenade.

There's video footage from the Saraqeb attack showing what's claimed to be the canisters falling through the sky, appearing to produce smoke or a white gas, as well as producing light. The canisters appeared to show signs of heat damage around holes along the body of the canister.  

Considering the various information gathered about these grenades is it likely they would have contained Sarin?

Not really – sounds like WP or CS

Is it possible the could have contained another substance that could have caused symptoms seen in the victims of the attack?

In the grenades? Seems far fetched and the mixing of liquid sarin and a riot control agent dissolved in to solution would be a beast to get stable as it could affect agent stability.

Could one of those possibly substances produced a false positive for sarin?

Not as far as causing death and not on the basis of the medical test results.

Is it reasonable that the contents of this grenade could have been emptied and replaced by sarin?

Possibly.

Khan al-Assal

The Russian government has claimed the Syrian opposition was responsible for the Khan al-Assal attack, with a DIY rocket delivering a payload of Sarin.  

What do you think would be involved in putting together a DIY chemical warhead for a DIY rocket?

Crude devices are not that hard. Removal of explosives or whatever payload had been carried, followed by introducing the agent. You would need protective gear and it wouldn’t be very safe doing the filling.

Accuracy would be lost (if a missile) and performance of rockets could be affected by different weight distribution. I don’t really want to go in to too much detail about the how, lest I give ideas or advice, but early CW munitions were very simple.

If you don’t really care where it goes then its achievable.

Considering the Russian government's claim that a DIY rocket was used  in the attack, what would be the most effective dispersal method once the rocket reached it's target?  

Air burst or base ejection were used by military munitions but require more complex fuses. If aimed at hard targets then you’d get a level of dispersal by simple impact, but if it hit the earth then the payload could just get driven in to the earth.

As with the other alleged chemical attacks in Syria the staff treating the wounded appear not to be using any protective clothing.  Would this have resulted in medical staff and responders being contaminated if this was a sarin attack?

Not necessarily, see above.

Chemical Weapon Specialists Talk Sarin, Saraqeb, and Khan Al-Assal - Part 1

Over the past few weeks, it seems all sides in the Syrian conflict have come to agree that sarin has been used in Syria, they just disagree over who used it.  Russia's UN ambassador recently gave the UN secretary general results of tests which he claims proves the attack on Khan al-Assal involved the use of sarin by the opposition Basha'ir al-Nasr brigade, using their DIY "Basha'ir-3" rockets.  Western nations have made various claims, including France who used samples collected from Damascus and Saraqeb, Idlib, by journalists from Le Monde to confirm the use of sarin in both these areas.

With the use of sarin in Syria being a frequent topic of debate I've approached a number of chemical weapon specialists with a set of questions on sarin, and the alleged attacks in Saraqeb and Khan al-Assal to help shed some light on the topic, and hopefully clear up some confusion.  

Paul from Allen Vanguard.  Allen Vanguard have a long established reputation for reporting on Threat Intelligence.  They recently rolled-out a new web portal that offers on-line access to their products and services.  The portal can be found here.  (Qualifying businesses and organizations can obtain guest accounts upon request, using the “Subscribe” button on the top right hand side of the page.)

Sarin

How is Sarin typically weaponised?

Sarin is a lethal war agent.  It is designed and produced to cause death in humans.  It is usually loaded into a carrier projectile which is designed to contain liquid agents.  Sarin can also be dispersed by other means such as aerosols.

If projectile delivered, an explosive burster charge is used to open the projectile and disperse the Sarin without destroying all of it.

What form does Sarin take?  Can it be liquid, gas, powder, etc? Does it have a particular smell or colour?

In its weaponised state Sarin is a colourless and odourless liquid and is dispersed either in that form or as a vapour.  That is not to say that a Sarin producer could not add ingredients to make it detectable either by sight or smell although this would require careful research to ensure that the precursors and additives did not interfere with each other.  It would be an unusual thing to do.

It would not be viable from an effectiveness standpoint to use powdered Sarin, just as it is not possible to have powdered water.  Sarin is volatile and able to disperse efficiently by being mixed with Isopropyl alcohol so that it can turn into a vapour and move with air currents and then either be inhaled by living organisms or through absorption.  If it was turned into a solid (powder) then it would be too heavy to be dispersed in an efficient manner.

Have you ever heard of Sarin being used in a diluted form, or mixed with other chemical substances to make it less lethal?

No.  The advantage of CW is that they are cheap, easy to disperse and able to kill/injure a large amount of people.  The ratio between dead and injured will depend on the agent concentration and exposure, in what environment (indoors/outdoors) and in what atmospheric conditions (wind/ /temperature).

There would be little advantage of making Sarin less lethal because it would still be lethal in the right conditions.  If the objective of an attacker was to temporarily incapacitate an enemy then other CW would be considered such as mustard agents, then the attacker would be expected to physically enter that area to control it otherwise the attack would serve no purpose militarily.  In this scenario, the attacker’s soldiers/vehicles would be equipped with protective equipment/clothing otherwise they would be liable to be contaminated too.

Other agents, such as CS would be far more effective at causing non-lethal effects with the intention of temporarily incapacitating people and encouraging them to leave an area of their own accord.  ‘Mild’ nerve agent poisoning will mean that people will be more likely to stay in the area.

A number of reports have claimed to have proven the use of Sarin through tests on hair, clothing, blood, tissue, and urine samples.  How would these be tested for the presence of Sarin?

I would expect that each item would be analysed with the correct equipment which has been properly maintained and calibrated after each item has been analysed, otherwise one item could contaminate the rest of the tests, resulting in a higher cumulative result.  I explained in my Q&As with Alfred Hackensberg that there would be a requirement for tests to be taken of the environment and from local people who had not been killed or injured in the attack to compare blood samples.  To be digested and turned into urine, the victim would have had to have consumed such a small amount in another liquid that it would not have killed them.  If they had been killed by drinking Sarin, it would not have entered the digestive system.

But anyway, to answer the question, all the items would be tested for traces of the lethal precursors of Sarin and in the case of the blood, the evidence of asphyxia, the method by which Sarin will ultimately kill its victim.

If Sarin was detected in hair and urine wouldn't that suggest small, non-lethal quantities, being ingested over a period of time?  

Yes.  If someone was killed from Sarin CW attack then the Sarin would not be digested or grown out into someone’s hair.  If they had been attacked and survived in the past, they would have told someone about it, there would have been more witnesses and it is possible that the attack would have left permanent indicators of its presence, such as in the hair of the survivor.

If Sarin was on clothing how hazardous would it be to handle that clothing without correct protection?

If recently contaminated and not subjected to any decontamination procedures, then there would be a contamination risk, especially in confined spaces.  Individual protective clothing (IPE), respirator with correct filter would be required to be worn by everyone coming into contact with it.

Is it possible other substances could produce false positives for Sarin?

Yes it is.  Most chemical agents are detected in the field using generic technologies.  Precise field detection is possible through reagent kits but this requires training to use accurately.  As an example of detecting a false positive, insect repellents work in much the same was as nerve agent by attacking the nervous system of the insects and even in small quantities, they will cause electronic portable detector systems to alarm.  The quantities of active agent in insect spray are diluted so that they won’t harm humans for normal use, although it is likely that it will be ingested by people who use such substances on a regular basis.

After a suspected Sarin attack how should the victims be processed, and what precautions should be taken?

This very much depends on who is suspected of being a CW victim (military or civilian) and what infrastructure (qualified medical staff, suitable vehicles, and suitable accommodation) is in place to deal with CW attacks.  The more resources applied, the more costly but effective the process.

Nations have their own procedures, but some basic principles need to be adhered to; minimising further contamination, transferring CW victims into vehicles and then to a hospital will ensure that the vehicles can no longer be used until decontaminated and the people in the hospital who were not CW victims would become at risk of contamination.  It is possible to have sealed wards but it would be difficult to obtain video footage from inside the contaminated area as there would need to be a comprehensive system of decontamination for anyone leaving.  All the staff would need to wear IPE and be cognisant of symptoms, decontamination drills and procedures.

The most efficient method of delivering aid to CW victims would be to bring the suitably trained medical staff to the victims so that they can be treated and processed, decontaminated and then transferred to an aid post or hospital.

Setting up a hot line and cold line upwind of the incident is the normal process for chemical incidents controlling access and egress to/from the hazardous area with detection, decontamination and casualty handling incorporated into the mitigation process.

The corpses of CW victims would likely be burned to avoid further contamination of the ground, other people or buildings.

If these precautions are not taken what is likely to happen to the people coming in contact with the victims?

A person with contaminated clothing is further dispersing the agent.  Anyone coming into contact with a contaminated person will be at risk of becoming contaminated themselves, especially in confined areas such as in buildings or vehicles.

How long would it take Sarin to become harmless, or dissipate?  In general terms are we talking minutes, hours, weeks? 

This is difficult to answer because of the variables that could exist but Sarin is a non-persistent and highly volatile liquid which disperses and vaporises rapidly dependent on conditions of temperature and air flow.  A single projectile of Sarin fired in a hot, sunny featureless environment during a windy day could feasibly take minutes to dissipate.  At the other end of the spectrum, a sustained bombardment/barrage in an urban area during a period of no wind and no sustained periods of sun would be more likely to create a scenario where pockets of exposed Sarin would last for days, unexposed Sarin could last for weeks and CW UXO could remain in the area for years.

Sarin is a non-persistent agent which means that the entity who used it is intending to enter the contaminated area soon after the attack when safe to do so.  IPE and detection equipment would be used by first-in elements and until the all-clear was given.  

Saraqeb

The Saraqeb attack is probably one of the mostly well documented alleged chemical weapon attacks of the conflict.  Canisters inside containers filled with white-grey powder were reportedly dropped from a helicopter, landing in two locations, one near a road, where no victims were reported, and the other in the courtyard of a family home.  It was reported that immediately after impact, one of the residents entered the courtyard, and collapsed shortly afterwards, later dying.  Shortly after the first victim entered the courtyard more members of the family entered, and also fell ill, as did people responding to the attack.  Between 11 to 13 people were reportedly effected, with only one death reported.  Video from the road-side location filmed some time after the attack would show children playing near to the remaining white-grey powder with no ill effects reported. (A more detailed breakdown can be found here)

Would the above scenario match what you'd expect to see if Sarin has been used in the attack?

Not really.  I would be very surprised if a lethal war agent would be dispersed in this way; the risk of contamination to the helicopter and crew would be high.  Sarin is not known to be dispersed in a powdered form.

In common with many alleged chemical attacks in Syria the medical staff appears to have no protective gear.  If this was a Sarin attack, how likely would it be that the medical staff would be effected, and how long would it take for the medical staff to become effected?

Depending on concentration and method of contact, the medical staff could feel the effects of the agent as soon as they came into contact with the victim or other contaminated articles.

One video shows a car pulling up with at least one victim inside.  If this was a Sarin attack, how likely would it be that the inside of the vehicle would be contaminated by Sarin?  If the victim inside the vehicle had been exposed to Sarin is it likely other passengers in the vehicle would fall ill?

The inside of the vehicle would likely be contaminated by Sarin if the victim has been in contact with the agent droplets or vapour.  The victim would have contaminated skin and clothing which would continue to produce Sarin vapour.  The inside of a vehicle is confined and this would mean that everyone in the vehicle would breathe in the Sarin.  Contaminated surfaces inside the vehicle could affect future users of the car.

Some people have proposed a scenario where a diluted mixture of Sarin and other substances was used in the attack.  If that was the case, would your answers to the above questions change significantly?

I don’t understand why a diluted Sarin agent would be produced or used.  If a less lethal agent was required then there are more efficient solutions.

The canisters recovered from the scene of the attacks matched canisters also recovered from an attack reported in Sheikh Maqsoud in Aleppo, where there were again claims of them being dropped from a helicopter, with photographs showing the canister remains covered in white-grey powder.  

The same design of canister has also been filmed in a cache of weapons reportedly captured by the Syrian opposition from the Syrian military, and a journalist in Syria has shown the image of the canister to various armed group, many of which have claimed to have seen them in the possession of opposition fighters, claiming to have captured them from the Syrian army.

Another type of grenade, using an identical fuze, was also photographed in Syria, with the photographer being told it was a normal smoke grenade.

There's video footage from the Saraqeb attack showing what's claimed to be the canisters falling through the sky, appearing to produce smoke or a white gas, as well as producing light. The canisters appeared to show signs of heat damage around holes along the body of the canister.  

Considering the various information gathered about these grenades is it likely they would have contained Sarin? 

Not really. Hand grenades have been manufactured for military use containing lethal war agents in the past.  Sarin filled grenades would not include a pyrotechnic burning reaction to generate the toxic smoke as this is not deemed viable or known for dispersal of a Sarin payload.  

Is it possible they could have contained another substance that could have caused symptoms seen in the victims of the attack?

It is unlikely that the grenades would have contained a blood, nerve or blister agent.  Having seen the footage of the victims, I question whether their symptoms were caused by a CW attack.  Without seeing more footage before and after the filming, I’d say that they could have been exposed a number of chemical incidents including toxic smoke inhalation, exposure to industrial chemicals or unintended releases through acts of war.

Could one of those possibly substances produced a false positive for Sarin?

It depends on the chemicals involved.  If they were precursors for insect-spray then possibly but it is unlikely that the agent would have been dispersed by means of a grenade from a helicopter.

Is it reasonable that the contents of this grenade could have been emptied and replaced by Sarin?

No.  The safe conditions and process required would be the limiting factor as the procedure would be highly dangerous with a high risk of contamination.  The gains in filling a small container with a highly volatile lethal agent, which can only be projected over short distances, would seem a risky and unviable proposition.

Khan al-Assal

The Russian government has claimed the Syrian opposition was responsible for the Khan al-Assal attack, with a DIY rocket delivering a payload of Sarin.  

What do you think would be involved in putting together a DIY chemical warhead for a DIY rocket?

The rocket would need a viable motor to be able to reach its intended destination.  There would need to be a method of breaking or bursting the warhead casing in order for the Sarin to disperse.  It is possible to separate the Sarin precursors inside different containers inside the warhead (binary agent) but this further complicates the functioning of the projectile and makes successful use less likely if an improvised system.

The Syrian opposition have the technical know-how to manufacture rockets.

Considering the Russian government's claim that a DIY rocket was used  in the attack, what would be the most effective dispersal method once the rocket reached it's target?  

Most efficient would be use of a projectile with an air-burst fuze to allow the Sarin to be dispersed above the ground as to contaminate as much of the area as possible.  I would also expect that some of these rockets would miss the target wildly, contaminate the wrong targets and in some cases not initiate properly.  Simple impact of a thin cased projectile with the ground could be used to disperse the liquid which would then vaporise depending on environmental conditions.

As with the other alleged chemical attacks in Syria the staff treating the wounded appear not to be using any protective clothing.  Would this have resulted in medical staff and responders being contaminated if this was a Sarin attack?

Yes.  Everyone within a contaminated area would feel the effects of chemical attack, resulting in injury and death.  I would be surprised if Sarin victims would be able to be transported to a hospital immediately after an attack without secondary contamination occurring.

------------------

Hamish de Bretton-Gordon is the Former Commander of UK CBRN Forces and COO of SecureBio.

Sarin

How is sarin typically weaponised?

Sarin is generally stored in its component form (separate chemicals) and is weaponised by the mixing of the components into either a liquid or vapour/gas form.  Once 'mixed' Sarin has a relatively short shelf life and would therefore need to be used within a time frame.  If not used then purity will degrade and the effectiveness/lethality will be effected.   Sarin was developed by the Nazi’s in the 1930’s originally as a pesticide and has its origins as an organophosphate.  When they realised how effective it could be as a nerve agent against humans they weaponised it. Sarin is about 3-4000 times more toxic than organophosphates, hence the poisoning of Indian School children last week with pesticide where 23 people were killed would have been significantly worse if it were Sarin or another Nerve agent. 

What form does sarin take?  Can it be liquid, gas, powder, etc? Does it have a particular smell or colour?

Sarin will generally come in the form of either a liquid of vapour.

Sarin, when in a pure form is both colourless and odourless.  However persons who were affected during the Tokyo Sarin attack,(the Sarin used was of only 50% purity)  reported a smell similar to paint thinner.  

A number of reports have claimed to have proven the use of sarin through tests on hair, clothing, blood, tissue, and urine samples.  How would these be tested for the presence of sarin?

The testing of cholinesterase levels in the samples during laboratory tests would indicate the presence of nerve agents.

If sarin was detected in hair and urine wouldn't that suggest small, non-lethal quantities, being ingested over a period of time?  

Not necessarily, it could indicate that the person was only exposed to a small amount regardless of the time involved. 

If sarin was on clothing how hazardous would it be to handle that clothing without correct protection?

This would depend largely on the quantity on the clothing and the quality/age of the Sarin.  However, a note of caution, is that exposure to Sarin can be accumulative and death or injury could occur over a time when exposed to low levels of contamination.  The best advice is to protect yourself at all times.

Is it possible other substances could produce false positives for Sarin?

Highly unlikely with today’s modern equipment which can measure to PPM PPT levels.  Some of these tests have been done at Porton Down and US and French equivalent, who conspiracy theories aside, would not get this wrong.

After a suspected sarin attack how should the victims be processed, and what precautions should be taken?

Victims will need to be triaged and treated according to medical need.  Staff treating victims should protect themselves at all times to prevent them in turn becoming victims.  Many first responders and medical staff in the Tokyo subway attacks became casualties themselves in this way.

If these precautions are not taken what is likely to happen to the people coming in contact with the victims?

Likely to become affected by the Sarin to a greater or lesser degree.

How long would it take sarin to become harmless, or dissipate?  In general terms are we talking minutes, hours, weeks? 

This will depend on a number of factors, but it will become harmless in a relatively short period, hours rather than days.  Sarin by its very nature is a non persistent agent and is lighter than air, therefore it will disperse quickly.  The speed at which it disperses will depend on temperature, humidity etc.  Generally speaking the lethal effects of Sarin are short lived, residues can remain in the soil or in clothing for weeks.  Traces of Mustard gas, a persistent blister agent are still being found in Halabja 25 years after the attack.

Saraqeb

The Saraqeb attack is probably one of the mostly well documented alleged chemical weapon attacks of the conflict.  Canisters inside containers filled with white-grey powder were reportedly dropped from a helicopter landing in two locations, one near a road, where no victims were reported, and the other in the courtyard of a family home.  It was reported that immediately after impact one of the residents entered the courtyard, and collapsed shortly afterwards, later dying.  Shortly after the first victim entered the courtyard more members of the family entered, and also fell ill, as did people responding to the attack.  Between 11 to 13 people were reportedly effected, with only one death reported.  Video from the road-side location filmed some time after the attack would show children playing near to the remaining white-grey powder with no ill effects reported.

Would the above scenario match what you'd expect to see if sarin has been used in the attack?

Not normally.  Sarin would normally be delivered by air dropped munitions or artillery shells, causing mass casualties i.e. Halabja.  However, it is pretty clear that samples from Saraqeb have tested positive for Sarin, so there would appear to be very small amounts of Sarin contained in the canisters, probably of a low quality.  This would account for the relatively few casualties.  It is certainly not textbook delivery but has presumably achieved the effect which the perpetrator wanted – confusion and derision amongst the International Community.

In common with many alleged chemical attacks in Syria the medical staff appears to have no protective gear.  If this was a sarin attack, how likely would it be that the medical staff would be effected, and how long would it take for the medical staff to become effected?

Without PPE medical staff would be vulnerable to cross contamination issues. The levels of exposure are likely to be low but as mentioned above the accumulated effects could cause injury or death.  The lack of PPE and training is also a concern for NGOs and charities operating in a medical capacity in Syria.

One video shows a car pulling up with at least one victim inside.  If this was a sarin attack, how likely would it be that the inside of the vehicle would be contaminated by sarin?  If the victim inside the vehicle had been exposed to sarin is it likely other passengers in the vehicle would fall ill?

There would in all likelihood be contamination inside the vehicle, however on the evidence given this would low level.  Other occupants of the vehicle would be contaminated to one degree or another.  Very difficult to tell from videos and pictures.

Some people have proposed a scenario where a diluted mixture of sarin and other substances was used in the attack.  If that was the case, would your answers to the above questions change significantly?

The subject of deliberately diluting a mixture of Sarin, and or mixing it with other substances would defeat the object of use it as it was designed, and the effectiveness would be difficult to predict. The less pure the Sarin is the less lethality it possesses.  Therefore the answer above would remain.  It is probably the case that less lethal Sarin was used, but it is impossible to say if this was by accident or design.

The canisters recovered from the scene of the attacks matched canisters also recovered from an attack reported in Sheikh Maqsoud in Aleppo, where there were again claims of them being dropped from a helicopter, with photographs showing the canister remains covered in white-grey powder.  

The same design of canister has also been filmed in a cache of weapons reportedly captured by the Syrian opposition from the Syrian military, and a journalist in Syria has shown the image of the canister to various armed group, many of which have claimed to have seen them in the possession of opposition fighters, claiming to have captured them from the Syrian army.

Another type of grenade, using an identical fuze, was also photographed in Syria, with the photographer being told it was a normal smoke grenade.

There's video footage from the Saraqeb attack showing what's claimed to be the canisters falling through the sky, appearing to produce smoke or a white gas, as well as producing light. The canisters appeared to show signs of heat damage around holes along the body of the canister.   

Considering the various information gathered about these grenades is it likely they would have contained sarin?  

Given the evidence above the canisters would more likely contain phosphorous, or indeed be smoke grenades.  But it is not impossible that they contained Sarin.  

Is it possible the could have contained another substance that could have caused symptoms seen in the victims of the attack?

It is possible that they could have contained organophosphates(pesticides) which have the sample chemical structure as nerve agents but are a lot less toxic and would fit with the scenario painted.  However, UK, US and French Govts have stipulated that they have detected Sarin in samples from the two attacks mentioned and that is the best information currently available.

Could one of those possibly substances produced a false positive for sarin?

It is highly unlikely that a false positive would be given for Sarin.  Lab tests on biological samples are very sophisticated, and again modern day detection, identification and monitoring equipment systems are pretty reliable. 

Is it reasonable that the contents of this grenade could have been emptied and replaced by sarin?

It is possible, but I’m not sure it is reasonable. It would be a very strange thing to do and potentially very dangerous to those doing this.  However, there appear to be no bounds to the ‘awfulness’ associated currently with the War in Syria, so one is surprised by very little at the moment.

Khan al-Assal

The Russian government has claimed the Syrian opposition was responsible for the Khan al-Assal attack, with a DIY rocket delivering a payload of sarin.  

What do you think would be involved in putting together a DIY chemical warhead for a DIY rocket?

This scenario is highly improbable.  Sarin when delivered by munitions is 'mixed' in flight and the warhead is programmed to either release its payload at a given height or on contact with the ground.  It is unlikely that the rebels would have access to this level of sophistication – this is beyond a ‘DIY’ rocket ‘thing’..

Considering the Russian government's claim that a DIY rocket was used  in the attack, what would be the most effective dispersal method once the rocket reached its target?  

If this claim was found to be justified the either an air burst or ground burst weapon would be equally effective.  There would be a number of factors to take into account before deciding which would be the best, these could include climatic conditions, target etc.

As with the other alleged chemical attacks in Syria the staff treating the wounded appear not to be using any protective clothing.  Would this have resulted in medical staff and responders being contaminated if this was a sarin attack?

It is highly likely that some form of cross contamination would occur from treating the victims, the level of contamination would be determined by the level of contamination the victim was exposed to.

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Later next week I'll be posting more interviews, and looking at what we know about the Russian claims of sarin use at Khan al-Assal, and the group they claimed used it, the Basha'ir al-Nasr brigade.

Anti-Materiel Rifles In Syria

One type of weapon that is repeatedly sent to me for identification is the anti-materiel rifle, three types of which have been sighted in Syria.  Here's a quick reference guide to all three.

OSV-96

A Russian made rifle produced in the 90s, and used by the Syrian military.

M99

A Chinese rifle used by the Syrian army that was mistaken for a British AS-50.

HS.50 Copy

While at first this appears to be an Austrian Steyr HS.50, it's actually a near identical Iranian copy.

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Unexploded Cluster Bomblets Repurposed As DIY Rocket Warheads

The DIY Weapons Of The Syrian Opposition

You can contact the author on Twitter @brown_moses or by email at brownmoses@gmail.com