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What to Watch Out For in the Upcoming OPCW FFM Report on the Douma Chemical Attack

May 30, 2018

By Eliot Higgins

Translations: Русский

In the coming weeks it is expected the OPCW Fact Finding Mission (FFM) will release its report on the April 7 2018 chemical attack in Douma, Damascus. The purpose of the OPCW FFM is to establish whether or not chemical agents were used, not to assign blame. Prior to Russia vetoing its renewal at the UN Security Council, the OPCW-UN Joint Investigative Mechanism (JIM) would have investigated any chemical incidents that had been deemed likely to have occurred by the OPCW FFM, but without the OPCW-UN JIM there is no official mechanism for investigating and assigning responsibility for chemical attacks.

Since the OPCW-UN JIM was not renewed, the OPCW FFM has reported on two chemical attacks, the March 30 2017 attack in Al-Lataminah, Hama, where it concluded “that sarin was more than likely used as a chemical weapon”, and the February 4 2018 attack in Saraqib, Idlib, where it concluded that it was likely chlorine was used as a chemical weapon. While the OPCW-UN JIM did not investigate either incident, Bellingcat has examined both incidents in detail, and concluded the Syrian government was responsible for both the Al-Lataminah and Saraqib attacks, with details in the OPCW FFM Saraqib report revealing the likely use of Sarin, along with chlorine, in the attack.

Without the OPCW-UN JIM, it is still possible to draw conclusions about who was responsible for attacks based on open source evidence and details published in previous OPCW FFM and OPCW-UN JIM reports. For example, Bellingcat concluded that the Syrian government was responsible for the Al-Lataminah attack based on a number of pieces of evidence. A specific design of filling cap documented by the OPCW FFM report on Al-Lataminah was also documented by the OPCW-UN JIM at the April 4th Khan Sheikhoun Sarin attack site, and described by the OPCW-UN JIM as “uniquely consistent with Syrian chemical aerial bombs”. “Marker chemicals”, described in the OPCW-UN JIM report on Khan Sheikhoun as “a strong indicator that the sarin disseminated in Khan Shaykhun was produced from DF from the Syrian Arab Republic stockpile”, were also found in samples examined by the OPCW FFM in their investigation of the Al-Lataminah attack. While it is not explicitly stated in the OPCW FFM report on the Al-Lataminah chemical attack that the Syrian government was responsible, there is plenty of information in their report to draw a solid conclusion.

Left, filling cap recovered from the Al-Latminah attack; Right, filling cap recovered from the Khan Sheikhoun attack

The upcoming OPCW FFM report on the Douma chemical attack may also contain information that allows conclusions about the chemical agents used and the origin of the attack to be drawn.

Signs of Chlorine and Sarin

Unlikely many chemical attacks, the OPCW FFM was able to access the sites where yellow gas cylinders reportedly used in the attack were found, and take samples. The OPCW FFM may also have acquired biomedical samples taken from victims, and biomedical and environmental samples provided by local groups. It is from these samples it will hopefully be possible to establish which chemical agents were used.

The earlier OPCW FFM report on the Saraqib chlorine attack, which has a number of similarities with the Douma chemical attack, contains details that are likely to be relevant to the Douma chemical attack. The below tables shows the results of chemical tests performed by the OPCW FFM:

What stands out in these tables are not the chemical products related to chlorine gas, but the chemicals abbreviated to DIMP, IPMPA, and MPA. These are not associated with chlorine gas, but have been detected in all Sarin attacks in Syria where chemical analysis was performed by the OPCW, including the August 21st 2013 Damascus attacks, the March 30th 2017 Al Lataminah attack, and the April 4th 2017 Khan Sheikhoun attack. The French National Assessment following the Khan Sheikhoun attack also include analysis of the munition used in the April 29 2013 Sarin attack in Saraqib that detected DIMP in the presence of Sarin.

What this tells us is the Saraqib chemical was not just a chlorine attack, but almost certainly included the use of the Sarin. Symptoms from the Saraqib attack also indicates the likely use of Sarin, or a Sarin-like substance, with one symptom presented by all victims being constricted pupils, one indicator of Sarin exposure, not chlorine exposure:

It has already been claimed by Western governments and local organisations operating in Douma that chlorine and a nerve agent were used in the April 7th attack, so the presence of chemicals related to Sarin, and symptoms consistent with the use of Sarin would be extremely significant. Unlike Saraqib, it is possible that biomedical samples were tested by the OPCW FFM, and previous OPCW reports contain test results from bio-medical samples taken from victims of Sarin attacks. In the OPCW-UN JIM report on the April 4 2017 Khan Sheikhoun Sarin attack multiple blood samples were recorded at testing positive for Sarin or Sarin-like substances, while urine samples tested positive for Isopropyl methylphosphonate (IMPA), a degradation product of Sarin.

Biomedical samples taken from the corpse of a victim of an earlier Sarin attack in Saraqib in April 29 2013 and published by the United Nations Mission to Investigate Allegations of the Use of Chemical Weapons in the Syrian Arab Republic provides information about what might be detectable when a victim has died:

IMPA again is used to confirm the use of Sarin in a chemical attack, and if IMPA is detected in samples from the Douma chemical attack it will be clear that Sarin was used. The question is then, where did the Sarin come from?

The OPCW-UN JIM report on Khan Sheikhoun describes three chemicals found in tests of samples from Khan Sheikhoun as chemical markers which presence is a strong indicator “that the sarin disseminated in Khan Shaykhun was produced from DF from the Syrian Arab Republic stockpile.” These chemicals are:

  • Phosphorous hexafluoride (PF6) aka Hexafluorophosphate (HFP)
  • Isopropyl phosphates
  • Isopropyl phosphorofluoridates

Importantly, the presence of HFP is evidence “that HF [hydrogen fluoride] was used to produce the DF that was the precursor for the sarin” and “HF is a very aggressive and dangerous gas and is, therefore, difficult to handle. The use of HF indicates a high degree of competence and sophistication in the production of DF and points towards a chemical plant type production.” The report also states:

Moreover, the results confirm that sarin was produced by the binary route, in which DF is combined with isopropanol (iPrOH) in the presence of hexamine.

Phosphorous hexafluoride (PF6) appears in samples from the March 30th 2017 Al-Lataminah attack, along with Isopropyl phosphorofluoridate, a second marker chemical described in the OPCW-UN JIM’s Khan Sheikhoun report, and Hexafluorophosphate (HFP) was present in samples from several metal pieces and munition fragments from August 21st 2013 attack sites, according to the UN report on the attack.

The presence of these chemicals in samples taken from Douma would not only confirm Sarin was used, but the Sarin came from the stockpiles of the Syrian military. Syria has repeatedly denied losing control of its chemical weapons stockpiles, so this would be the strongest possible indication that the Syrian government was responsible for the April 7 2018 Douma attack.

Munition debris

Two munitions were filmed and photographed following the April 7th 2018 attack, two yellow gas cylinders, one of which had an external structure. The second munition did not have an external structure attached to it when it was documented, but the remains of the same design of external structure were nearby, suggesting it was either removed during impact, or removed following the impact for as yet unknown reasons.

Remains of one of the chlorine bombs used in the Douma attack (source)

Identical yellow chlorine cylinders, some with matching external structures as those seen with the Douma munitions, have been repeatedly documented at the sites of previous aerial chlorine attacks, and the OPCW FFM report on the February 4 2018 chemical Saraqib attack includes detailed photographs that confirm the same type of munitions were used in both the Saraqib attack and Douma attack.

Recent OPCW FFM reports have included detailed photographs of munition debris, and have proven extremely valuable for matching debris to munitions used in previous attacks. What is yet to be explained is how Sarin was used in the February 4 2018 Saraqib attack, as it is unlikely that Sarin was added to the chlorine gas cylinder, suggesting a yet undocumented munition or container attached to the chlorine cylinder was used. If signs of Sarin use are detected in the Douma attack, hopefully the OPCW FFM will be able to show the how Sarin was deployed.

Eliot Higgins

Eliot Higgins is the founder of Bellingcat and the Brown Moses Blog. Eliot focuses on the weapons used in the conflict in Syria, and open source investigation tools and techniques.

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  1. Sean Lamb

    What I find fascinating about this is the extra-ordinarily complicated way Assad goes about delivering his militarily pointless sarin attacks.

    Sarin is an extremely simple and safe weapon when delivered in the orthodox manner. You have one compartment of precursor 1 and the other compartment of precursor 2 – when you fire the rocket or drop the bomb, the membrane separating the two compartment breaks and the two precursors mix and sarin is formed during the flight. Simple, safe and deadly to the target.

    What Assad seems to be doing is creating sarin, allowing the volatile liquid to turn to gas and then pumping in chlorine gas. Then using a compressor to fill up gas cylinder bottles before dropping them out of helicopters. What the precise advantage of doing this is anyone’s guess

    Or alternatively the jihadists have just been contaminating the cylinders before the OPCW tests them.

    On a lighter note: Congratulations to the Ukrainian SBU for their well delivered Babchenko prank. Do you think they were poking fun at MI6 and the Skripal saga?

    • Jean Pascal Zanders

      What I find fascinating about this reply is the lack of realisation that the USA (of all countries) never fully mastered this “simple and safe” binary technology and eventually abandoned its development and production when it realised that one of the precursor chemicals needed was only available from plants in Switzerland and India.

      (Following the US campaign against Germany for aiding the CW production facility at Rabta, Libya, both countries were of the opinion that the non-proliferation standard applied to the USA too, and therefore declined to export the otherwise legitimate chemical.)

      • Sean Lamb

        These claims are not simply wrong, I am unable to even find some basic point that has been misunderstood on which they are derived.

        It is like it has just been plucked randomly from thin air, in the same way someone might casually announce “Of course everyone knows that Robert Mueller is having an affair with Kendall Jenner.” And delivered with such confident self-assurance that people start to wonder perhaps Mueller and Kendall Jenner really are an item.

    • Sam

      “jihadists” and the whole reference to Babchenko/Skripal gave you up, but you are on the right track. Few more iterations and you may actually pass for a “Sean Lamb” instead of a russian government troll that you are.

      • Anonymous

        So everyone that disagrees with your opinion is a russian troll? How pathetic.
        Fact is that OPCW did not encounter any nerve agent used in douma.
        But yeah, believe a blogger and open source info as a fact.

    • Kostja

      First of all, there is no evidence that Syria actually did posess in-flight mixing technology when it comes to Sarin.

      Second of all, this technology is not “simple”.

      Third, even If they did posess it, the remnants of the munitions would, if found in the aftermath of an attack, be conclusive evidence that the government did it. Obviously, they would want plausible deniability.

      For the jihadists to contaminate cylinders (or any other samples) before the OPCW could test them, they would need to posess Sarin produced by using DF from the Syrian government, which they don’t have. So that theory is nonsense.

    • muchandr

      Except that one of the sarin precursors is sufficiently corrosive to attack lab glass and concrete. You’ve got some special Tupperware I hear?

      Chlorine is extremely corrosive to steel and copper alloys, making it very difficult to make a compressor or pump that won’t immediately break. I’ve only seen those in tiny sized for lab bench use. They use solid PTFE (Teflon) membranes that barely move. If you use conventional reciprocating pistons or rotors on metal-corroding gases, you’ll drag some into your lubricating oil and the thing will seize. Just look how rusty the burst cans are inside. That goes much faster when chlorine is around, took mere hours!

      Assuming the cans weight about as much as an average human, their terminal velocity is on the order of 120 mph. They will not burst on their own bumped at that speed even if filled with flammable and explosive gas like propane. Chlorine is liquefied inside, developing pressure of less than 6 bar at 20 deg outside. That looks opposite of “volatile” to me.

  2. Neverevermind

    OK ive no time for this but it sounds interresting 😉
    –comment above …
    –chemically…it needs some time to react 10-15 mins i think, and reaction-accelerators ….mmmmhhhh heat will destroy most, so no explosion
    (therefore every country has military specialists (usa/egland-prefered-logically-neutral) which remain silent, and let propagandhi work ((((i personally think MOST of them have sarine-precursor and also some of the “posphoamin”-socalled “””developements”””—PLLLZZZZ dont let one off this depending two stories getting out off attention i think they depend somehow))))
    !!!!!!IMPORTANT: if someone wanna tell you that a decoy agent found is a agentsample of XY-countries synthesis ….IT IS FUCKING NO PROOF FOR ANYTHING!!!!!


    finally …theres not only one evil side…yes right ….BUT THERE IS MORE THAN assad and rebels!!!!!
    there are also
    -MERCENARIES of russia, usa confirmed +div. other countries or indirect hired (industries and co …from thisone as a journalism, you will be pranked ……but reuters, dpa, ……….surely not…lol)
    – SOLDIERS OF NEIGHBOUR AND MORE DISTANT COUNTRIES (u.a turkyie, +/-curds, iran, ISRAEL, russia, england, usa, +X(also surely some eu))
    – AND MANY MORE (dont know where to put saudis and co)

    (chemical waragents, nuclear bomb, religion….made only responsible, for whole humanity standing, non propaghandistic governments which make only what they are made for and this is freedom ….mmmmhhhhh they DO NOT accuse and dominate and frighten countries for and because !!!!!!
    jup its only sarin, non democracy, ethics and this stuff that matters

    …ISRAEL …maaayyybbeee give them 2 or four atom bombs of your “reservoir” …. they dont have to be frightened by others anymore, they will know you have more bombs, but you have given them their right of self-determination, whats a reason FOR FREEDOM AND RECONCILLIATION, the self-determination not the bombs 🙂 ……naaahhh 3-4 nuclear bombs are a worse threat…. they could reach only you, the right of self-determination the whole world!!!!!! , that would be a real “doing all to not let it happen again”, not this shit you try to justify at the moment

    they make same shit again, separate, make differences, blame someone, prosper … and it all goes the wrong direction (comiunism, capitalism, own prosper before rest of world …hello IT DONT WORK, ALL OF IT…..)…. is this all what goverments are made and paid for …..leading aggression in wrong directions?

    (sry for bad english) bebe

  3. Christopher

    You’re forgetting to mention one important fact in your article regarding the #OPCW release into the alleged #Douma chemical attack. That is, UK, USA and co. also veto’d Russia’s counter (JIM), don’t hide any IMPORTANT facts Eliot. Why not include it? So one sided.

    • Francois Labelle

      Russia is the country that refused JIM…and Russia is the country that prevented the OPCW from being able to lay blame or responsibility! nice try troll!!

  4. Conglomera

    “Prior to Russia vetoing its renewal at the UN Security Council”
    US & Co. also vetoed the resolution adjustment made by the Russians where “CW usage by Syrian government” mentions were removed as well as replacing the appointment mechanism of the OPCW panel members from “appointed by members of the Security Council” to “appointed by the OPCW with the option for any SC member to revoke any (personal) member from the proposed delegation”.

  5. muchandr

    Did anybody bother to explain why does Assad’s evil wicked clandestine chemical weapon program keeps using EN 1089-3 standardized solid yellow color for chlorine? (a lot more in German version)

    Doesn’t he deserve some kind of ribbon for his great attention to hazmat storage and transport safety. Sarin should be grey with yellow shoulder, I figure 🙂

    • DoctorExplosion

      That’s probably due to the issues that muchandr mentions above. Syria buys canisters of chlorine via legitimate means, and for legitimate purposes, and as far as I can tell never tried to weaponize it until after the revolution began. So they don’t have the chemical infrastructure to handle chlorine munitions and instead weaponize commercially obtained chlorine canisters. The corrosive effects of chlorine would make transferring the gas to another canister a counterproductive and wasteful exercise.

      I guess they could just paint over the canisters, but what exactly would that accomplish? The yellow safety paint that the canisters come from the factory with are useful to soldiers handling the canisters too, so why would they want to create an unnecessary safety hazard?

      • Francois Labelle

        Do we know where does Syria gets to buy the chlorine gas?? Thanks for your very detailed, incredible work!

  6. Adrian Kent.

    Can you tell me where you got the picture of the Khan Sheikoun bomb-fragment
    from? Thanks.

  7. Charlie

    Well, the OPCW has published its Interim report (of particular interest because it is the first with chain-of-custody records):
    and none of the stuff mentioned here whatsoever showed up.

    No nerve agent related chemicals detected anywhere, no evidence of chlorine gas, not at any of the sites of the alleged attacks, not at the hospital, not in the biomedical samples from the supposed victims. It was also reported that the Syrian government agreed that bodies of supposed victims could be exhumed for testing, but it appears that none could be retrieved.

    NOW, how do we account for the horrifying scenes filmed in the Douma hospital by the White Helmets?


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