In a long-awaited report, the Organisation for the Prohibition of Chemical Weapons (OPCW) has blamed the Syrian regime’s air force for a chemical attack in 2018 that killed at least 43 people in Douma, near Damascus. The international watchdog’s findings are not a surprise — it had previously reached the same conclusion about two other attacks involving the same substance. Yet the report is highly significant nonetheless, because the OPCW’s efforts to investigate the Douma attack became the subject of a persistent disinformation campaign orchestrated by Russia and fueled by self-styled “anti-imperialist” activists in the West. The new 139-page report by the OPCW’s Investigation and Identification Team (IIT), released on Jan. 27, 2023, is a relentless demolition of these conspiracy theories surrounding the attack.
The essence of the disinformation campaign was a refusal by its purveyors to accept that the Bashar al-Assad regime was conducting chemical warfare in Syria. Instead, they claimed all such attacks were “staged” by rebels to frame the regime and trigger a Western intervention. There was never any evidence for this, but it became the deniers’ standard response to reports of chemical attacks. The main reason the Douma attack in particular became a cause celebre for the deniers is it was one of only two chemical attacks (out of a total of over 300) that did in fact result in punitive airstrikes by Western powers. In addition, for the deniers, the emergence of two dissenters from within the OPCW and a series of leaked documents kept the issue alive longer than might otherwise have been expected. Meanwhile, Russia’s attempts to shield its Syrian ally led to political divisions in the OPCW, which threatened to undermine the global prohibition against chemical weapons.
The OPCW’s Douma investigation began with the dispatch of a Fact-Finding Mission (FFM), which took samples for analysis, interviewed witnesses and gathered other evidence. This FFM found what it called “reasonable grounds” for believing a toxic chemical — “likely” to have been chlorine — was used as a weapon. The problem, though, was holding anyone accountable. The FFM’s role was limited to determining whether or not a chemical attack had taken place; its brief did not extend to investigating who might have been responsible. That task had been assigned to the Joint Investigative Mechanism (JIM) — a separate body created in 2015 by the U.N. Security Council for the purpose of identifying culprits.
The JIM began reviewing a list of chemical attacks previously confirmed by the FFM. By the end of 2017, it had reached conclusions about five of them, attributing two sulfur mustard attacks to Islamic State fighters and blaming Syrian government forces for one Sarin nerve agent attack, as well as two others involving chlorine. For Russia, such findings were inconvenient, so it alleged the JIM had become a tool against the Syrian government and used its Security Council veto to bring an end to its mandate.
Russia’s shutdown of the JIM prompted calls from the U.N. secretary-general and others to create a replacement. The result was the aforementioned Investigation and Identification Team, or IIT, established under OPCW auspices. Russia opposed its creation but was outvoted at a special meeting of OPCW member states. The IIT began looking into nine cases in Syria and, before last month’s report on Douma, had identified the perpetrator in four cases: two Sarin attacks and two chlorine attacks, all of which it attributed to Syrian government forces.
At the center of the Douma investigation were two yellow-painted gas cylinders, each more than 4 feet in length, which the FFM had identified as the “possible” sources of the chlorine used in the attack. One lay on a bed after apparently crashing through the roof of a building and bouncing off the floor. The other was on a balcony/patio, where it had seemingly pierced a hole into the room below.
One crucial question was how the cylinders got there, and the obvious explanation was that they had been dropped from the air — in which case, Syrian government forces had to be the culprit, since rebels did not have the use of any aircraft. Assad regime forces had long used helicopters to drop improvised bombs in the form of barrels stuffed with explosives, and on occasions they had also dropped chlorine cylinders. Cylinders used in this way were often wrapped in a steel frame or cradle with wheels and lifting lugs, making it easier to maneuver them in and out of helicopters. The frames also provided three tail fins to point the cylinder’s valve-end downward during its fall, so that the valve would break on impact and release the chlorine. Rigging of that type was found with the cylinders in Douma — a further indication that they had been dropped from the air.
Despite this, the deniers insisted the Douma attack had been faked by rebels. In 2019, a number of activists known as the Working Group on Syria, Propaganda and Media received a leaked document that appeared to support their claims. It was an internal — and unofficial — report by an OPCW employee, Ian Henderson, which said the cylinders were more likely to have been “manually placed” than dropped from the air. Noting that Henderson’s views had not been mentioned in the FFM’s final report on Douma, the group accused the OPCW of suppressing evidence and claimed it had been “hijacked at the top by France, U.K. and the U.S.” They preempted the IIT’s investigation by trying to cast doubt over the organization’s credibility.
Henderson had contended that the holes seen in the concrete could not have been made by the cylinders falling from the sky, implying that rebels had placed the cylinders there. The “balcony cylinder” had been found with its valve-end pointing into a hole in the concrete floor. Henderson questioned why the cylinder had stopped there and not pierced through. His computer simulations suggested that the cylinder would have carried enough energy to do so if dropped from a height of more than 1,600 feet. But, as the IIT’s report noted (in paragraph 6.289), that did not prove the cylinder wasn’t dropped from an aircraft — merely that it must have been dropped from a lower altitude, thus hitting the concrete with less energy. Further evidence compiled by the IIT showed the cylinders were indeed dropped by aircraft, and from an altitude well below 1,600 feet.
As for the second cylinder, found in a bedroom of a different building after apparently making a hole in the roof, Henderson wrote that “it was not possible to establish a set of circumstances” in which the cylinder could have passed through the hole without sustaining further damage beyond what was observed. “The dimensions, characteristics and appearance of the cylinders and the surrounding scene of the incidents,” he concluded, “were inconsistent with what would have been expected in the case of either cylinder having been delivered from an aircraft.” He also suggested the cylinder was too long to have passed through the hole above it. Yet, as the IIT analysis noted, the cylinder was 0.6 inches longer than the 26-inch hole only if one added the length of the flimsy fins, which were bent on impact. The hole was large enough for the cylinder to have passed through at an almost horizontal angle (paragraph 6.291).
The report concluded that the cylinders were dropped by at least one Syrian air force helicopter. It dismissed the idea that someone placed them in position, describing such a scenario as highly unlikely and unsupported by any evidence (paragraph 6.301). It stated:
Manual placement of the cylinders would have required the heavy and cumbersome cylinder’s assemblies to be carried up several flights of stairs, through narrow corridors and, in the case of the cylinder on the roof at Location 2 [the balcony cylinder], through a narrow door or through a small window opening. This sequence of actions would have had to have taken place at two different locations, and under the heavy shelling in the days and hours preceding the chemical attack in Douma. Furthermore, it would have had to have gone undetected and/or unnoticed in a densely populated urban area, considering the lack of supporting evidence (photographs, images, satellite/drone imagery) identified or obtained by the IIT. (6.299)
In its search for evidence of a chlorine attack in Douma, the FFM sent more than 100 samples for laboratory analysis. Interpreting the results proved complicated. When chlorine gas comes into contact with other substances, it reacts with some of them to form chlorinated compounds that can be detected later through laboratory testing. However, chlorinated compounds also occur naturally — so the problem was how to distinguish between compounds produced in a chemical attack and compounds that were already present in the environment. The investigators’ approach was to check for substances that could be caused by exposure to chlorine gas and then try to eliminate other possibilities. One example of this elimination process was a piece of copper electrical wire found hanging from the ceiling in the room below the balcony cylinder. The copper had acquired a green-colored patina, which forensic analysis showed was consistent with exposure to chlorine gas. Further analysis ruled out natural corrosion or exposure to saline conditions as causes of the patina, leading the IIT to view the wire as evidence that chlorine gas had been present in the room under the cylinder (paragraph 6.65).
Another substance of interest was trichlorophenol (TCP), which is not naturally present in wood but was found in all the wood samples from Douma. Laboratory experiments showed that TCP could be produced in wood by exposure to chlorine gas. The snag, though, was that it could also be produced by contact with sodium hypochlorite, which is the main ingredient in household bleach. Two of the wood samples also contained bornyl chloride (BC), which could be caused by chlorine gas, though only in wood from conifer trees. One of those samples came from the wooden support for a water tank in the basement where bodies were found. The other was a piece of wet wood found under the bedroom cylinder.
The IIT report commented: “Chlorine gas is the only chemical that, alone, would produce both BC and TCP in conifer wood” (paragraph 6.60). Generating BC and TCP without chlorine gas would need separate applications of bleach and hydrochloric acid, with thorough rinsing in between, it added (6.89). That would not happen accidentally and, as the report noted, there is no reason to believe anyone in Douma — even if hypothetically trying to deceive investigators as part of a “staging” scenario — would have thought of doing it deliberately. At the time of the attack, the ability of chlorine gas to produce BC and TCP in conifer wood was not common knowledge, even among scientists: It only came to light as a result of the OPCW investigation.
Viewing the chemical evidence in its totality, the IIT report emphasizes that a release of chlorine gas is the only realistic explanation, with no viable alternative scenario. The lab results simply could not happen by accident, and anyone seeking to fake the results would need to undertake an enormous amount of meticulous planning. In the building where the balcony cylinder was found, for example, they would not only need to apply a bleach solution but also adjust its strength “from the highest levels in the room directly under the cylinder to the intermediate concentrations at the crater’s edge on the fourth floor, to the low levels on the street,” the report stated (paragraph 6.86).
In October 2019, a former OPCW employee claimed there had been irregularities in the conduct of the FFM’s Douma investigation and questioned whether chlorine had actually been released. He presented his allegations at a small private gathering in Brussels organized by the Courage Foundation (an offshoot of WikiLeaks), which hailed him as a whistleblower. Initially known by the codename “Alex” and later identified as Brendan Whelan, he had been sent to Syria as a member of the FFM but, lacking the requisite safety training for deployment to Douma, he remained at the command post in Damascus. Whelan said he had emails, text messages and “suppressed draft reports” showing irregularities in the conduct of the FFM’s Douma investigation and claimed that evidence had been manipulated to reach a “pre-ordained” conclusion. As with the Henderson leak, defenders of the Assad regime saw it as proof that the FFM’s report was not only wrong in its findings but had also been deliberately falsified. Whelan’s supporters treated his allegations as fact, though several weeks passed without any sign of the apparently sensational documents in his possession. When eventually published by WikiLeaks, they failed to live up to the hype.
Whelan had been the principal author of an initial draft of the FFM’s report, running to 116 pages. As important questions remained unanswered in the draft, OPCW chiefs decided to issue a short interim report instead. It included some material from the initial draft but held back most of it, pending further analysis. There was nothing odd about this, but once it became public knowledge, Whelan’s initial draft acquired mythical status as a source of truths that had been “redacted,” “doctored” and “censored.” Yet by the time Whelan made his allegations, the FFM had published its final report on Douma, in which most of the supposedly censored material could freely be found, either in its original form or modified in light of further research and deliberation.
Another of Whelan’s leaked documents described a one-hour meeting with four toxicologists on June 6, 2018. The OPCW had been considering exhumation of bodies from Douma and wanted to check what this might achieve. According to this document, the toxicologists advised that, for a variety of reasons, including the time since burial, “there would be little use in conducting exhumations, as the chances of gathering evidence would be almost impossible.” It described the discussion then turning to the question of possible chlorine use. The toxicologists were shown photos and videos of victims and asked whether the signs and symptoms they saw were consistent with exposure to chlorine. According to this account of the meeting, “the experts were conclusive in their statements that there was no correlation between symptoms and chlorine exposure.” The toxicologists then considered other chemicals but “the only possibility that came to mind was some highly experimental and toxic carbamates … however they had low confidence in such a possibility.”
Since this account cast doubt on the use of chlorine, it caused much excitement among Whelan’s supporters, who cited it as an example of “suppressed” evidence because it went unmentioned in the FFM’s report. However, the meeting had been intended as an informal discussion and, at the time, no one was assigned to take minutes. It wasn’t until a couple of months later, shortly before leaving the OPCW at the end of his contract, that Whelan (one of the four staff present) decided to write “a summary of what I recall and had jotted in my notes.” This was the document later made public via WikiLeaks.
Whereas nerve agents, such as Sarin, leave traces that can be detected in humans some time after exposure, there is no equivalent test for exposure to chlorine. Because of that, and after discussions with more toxicologists, the FFM’s final report had stated: “It is not currently possible to precisely link the cause of the signs and symptoms to a specific chemical.” The recent IIT report’s conclusions are much stronger:
… while none of the symptoms described by victims and medical personnel are exclusive to chlorine exposure, when they are taken into consideration alongside chemical samples, clinical data, the distribution of fatalities, gas dispersion, ballistics, and the characteristics of the substance as described by survivors … these symptoms are consistent with those originating from chlorine gas exposure at high concentrations. (6.119)
The report also notes that the lab data point to chlorine and do “not support evidence of any types of chemical compounds except for chlorine” (6.116).
Deniers of the Douma chemical attack also needed some way to account for the bodies found at the scene that did not involve chlorine. Paul McKeigue, a prominent member of the aforementioned Working Group (and a professor at the University of Edinburgh), speculated that the dead were civilian captives who had been murdered by rebels in a gas chamber before being planted at the scene as part of the alleged “staging.” He offered no evidence for the hypothesis, and the IIT report discounted it as a possibility. By early morning on the day after the attack, it said, full rigor mortis had set in — indicating that death had only occurred about 9 to 16 hours beforehand (paragraph 6.117).
Deniers also disputed that a real chlorine attack would have killed so many people, arguing that the gas was not particularly lethal. That was true up to a point, but its lethality depends on how concentrated the gas is and the victims’ length of exposure to it. In many other previous chlorine attacks in Syria, people often had time to escape. Chlorine is heavier than air, and civilians in the past had evaded its worst effects by moving to upper floors when they noticed its distinctive smell.
In the building that contained the “balcony cylinder,” however, escape was difficult. The cylinder had fallen on the fourth floor and was discharging gas into the floors below. “The dispersion was so rapid that it obstructed the only possible escape route from the apartments via the stairwell,” said the IIT report. “Approximately 20 seconds after the release of chlorine, escape from the apartments on the third floor was almost certainly no longer possible and after 60 seconds escape from the apartments on the second floor was almost certainly no longer possible either” (paragraph 6.112). Some people had died on the stairs, others in the basement. Airstrikes with conventional weapons were taking place at the time and basements were ordinarily the recommended place to shelter. But, since chlorine is heavier than air, on this occasion, the basement was the most dangerous place to be. The choice was either death by bombing outside or death by gas inside.
What the IIT’s report shows, in considerable detail, is the enormous amount of planning and organization that would have been needed to fake the Douma chemical attack. This is something that conspiracy theorists don’t consider. They expect people to believe that Syrian rebels had the time and resources to engage in extraordinary theatrics in the midst of a desperate battle to stave off defeat. Douma lies in the Eastern Ghouta region, about 6 miles from the center of Damascus, which government forces had been steadily recapturing since February 2018. By March, the regime had succeeded in splitting Eastern Ghouta into three enclaves, each controlled by a different rebel militia. At that point, according to a French government report, “the Syrian regime’s political and military strategy consisted in alternating indiscriminate military offensives against local populations, which sometimes included the use of chlorine, and pauses in operations for negotiations.” Two of the armed rebel groups, Ahrar al-Sham and Faylaq al-Rahman, had accepted surrender terms that allowed fighters and their families to be bussed to northern Syria. The third group, Jaysh al-Islam (“The Army of Islam”), was still holding out. On April 4, some members of Jaysh al-Islam also accepted terms, but about 5,000 of them — mostly in Douma — refused. The regime resumed bombardment, and on April 7 it launched the chemical attack. Jaysh al-Islam surrendered the very next day.
Clearly, the chemical attack had hastened the regime’s victory. “According to insiders privy to the content of the negotiations and interviewed by the IIT,” the report says, “the pressure on the civilian population following the chemical attack, as well as the warning by pro-government forces that the shelling would continue and intensify had the group not accepted to negotiate, played a key role in the decision by Jaysh al-Islam’s leadership to eventually surrender” (paragraph 6.22).
Identifying the perpetrator of the Douma attack is an essential step toward accountability, though accountability itself is a long way off. Any further action will be a matter for OPCW member states and “the international community as a whole,” said Fernando Arias, the organization’s director-general, last month. The organization was established in 1997 to oversee the implementation of the Chemical Weapons Convention. Syria stands accused of flouting the convention — and not only because of its chemical attacks. On joining the convention in 2013, it was required to declare all its chemical weapons and related facilities so they could be destroyed. A decade later, it’s clear the regime’s declaration was incomplete. The most striking evidence of that came in the IIT’s first report, which held the regime responsible for two Sarin attacks in 2017 — after all its nerve agent stockpiles had supposedly been eliminated.
There was little the OPCW could do, so it set a 90-day deadline to resolve all outstanding issues regarding the declaration. When Damascus failed to cooperate, the OPCW suspended its voting rights and banned it from holding any office within the organization. Syria responded by escalating its non-cooperation and claimed the two cylinders at the center of the Douma affair — which it was required to safeguard as evidence — had been destroyed in an Israeli airstrike.
Assad has little to fear from the OPCW as long as Russian support for him continues. Russia’s first response to the latest IIT report was the usual collection of counterfactual absurdities, dismissing the report as a “fabricated concoction.” Russia doesn’t do this solely out of love for the Assad regime; it also has its own ax to grind regarding chemical weapons. Just a month before the Douma attack, there was the well-documented case of Russian agents poisoning Sergei and Yulia Skripal with a Novichok nerve agent in Britain. That was followed in 2020 by the attempted assassination of Alexei Navalny, the Russian opposition figure — again with a nerve agent. In both cases, Russia pursued a propaganda strategy similar to the one seen regarding Syria.
Russia will not accept the OPCW report because it could potentially open it up to similar scrutiny. It is equally improbable that the Assad regime’s Western supporters will admit error. Russia’s likely course will be to launch further attacks on the OPCW’s credibility and undermine the Chemical Weapons Convention. It is up to the rest of the world, then, to find a way for this body of evidence to serve the cause of accountability.
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