The difficulties of probing chemical weapons attacks in Syria

Hasan Mohamed, AFP | A rocket found in Eastern Ghouta, January 22, 2018.

The OPCW, the only international body authorised to investigate the use of chemical weapons, has carried out several inquiries after allegations of chemical attacks in Syria, despite the difficulty in collecting evidence on site.


While the Syrian government and its Russian ally deny any chemical attack in Eastern Ghouta on April 7, the Organisation for the Prohibition of Chemical Weapons (OPCW) has announced that a team will arrive there on Saturday to conduct an independent investigation.

The international body has a mandate to go to the scene of an alleged attack as soon as possible in order to attest to the harm it caused and to identify the toxic agents used.

‘Biological samples from victims’

“The inspectors will be able to do two things on the ground: they can get physiochemical samples from places affected by the attack – on the walls, on the ground – and they can take biological samples from victims, either wounded or dead, to look for metabolic evidence of a chemical agent in their fluids [urine and blood in particular]”, explained Olivier Lepick, associate researcher at the FRS (Fondation pour la recherche stratégique) think-tank in Paris, in an interview with FRANCE 24.

In the field, OPCW teams can interview victims, medical teams who have treated the victims, and any other witnesses to the incident. They can also attend autopsies and examine dead animals.

Before visiting the site of an alleged attack, they can analyse other evidence coming out of the area – from NGOs, media organisations, on social networks, and in official reports, if there are any.

At present it is mostly this kind of evidence that is available on the alleged attack in Douma. On April 7, the Syrian White Helmets and the Syrian American Medical Society said – as videos and witness statements attest – that a chemical attack had struck Douma, then the last pocket of rebel-held territory in Eastern Ghouta.

Accusing the regime of having used “toxic gas”, the two organisations have identified 40 people killed and 500 injured who have suffered from “breathing difficulties” and who give off “a similar smell to that of chlorine.”

‘There’s very little chance that they’ll go’

According to the World Health Organisation (WHO), “there were signs of severe irritation of mucous membranes, respiratory failure and disruption to central nervous systems of those exposed”. This evidence suggests it was likely that chlorine was used in the attack.

But investigators still need to go to the scene of the alleged attack, and that is almost impossible in Syria because of poor security conditions at such sites – they are often war zones. “There’s very little chance that they’ll go – the Russians and Syrians would have to protect the teams,” said Lepick. The Syrian government has announced that it has regained control of all of Eastern Ghouta and thus has complete control, along with its Russian ally, of the site.

“Every day that passes makes the results of any investigation less clear, and in this case the relevant area is controlled by the main suspects, who will be tempted to cover up the evidence,” Lepick continued. The researcher said that “bleach-style” cleaning is enough to remove traces of toxic agents on the spot, while the evidence in biological samples from victims becomes increasingly hypothetical with time and can be removed by the Syrian army. That is why the OPCW’s policy is to send teams 24 to 48 hours after the incident.

The organisation acknowledged this problem last year after the April 2017 chemical attack on Khan Cheikhoun, a rebel-held city in northwestern Syria. Unable to send teams to the scene of the attack for security reasons, the OPCW conducted its investigation in Turkey, where victims of the attack had sought refuge. “The scientific and probative value of visiting the site diminishes over time, particularly if it is not possible to manage access to the site,” said its report on the investigation.

Russian vetoes at the UN

Others have been able to conduct investigations in Syria to prove the use of chemical weapons. After the bombing of Khan Cheikhoun, French intelligence services carried out a probe concluding that sarin gas, a nerve agent, had been used – thanks to unexploded ordnance recovered from the area. This allowed Paris to confirm that the Syrian government was behind the attack.

In early 2013, two journalists from French daily Le Monde obtained samples (of blood, urine, hair and clothing) that doctors had collected from victims after a chemical attack in Jobar, eastern Ghouta. Urine flasks – analysed in a laboratory at the DGA (Direction générale de l'Armement), the weapons procurement and technology agency controlled by the French defence ministry – allowed them to prove that sarin gas was used.

The OPCW’s mandate is to investigate whether or not a chemical attack has taken place, and if so, what specific weapons were used. It is not supposed to establish responsibility for chemical attacks. But from August 2015 to November 2017, it worked with the UN in the shared framework of the Joint Investigation Mechanism (JIM), to identify who was responsible for chemical attacks in Syria.

JIM’s mandate was not renewed after several Russian vetoes at the UN.

This article was translated from the original in French

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