"The results show that no organophosphorus nerve agents or their degradation products were detected in the environmental samples or in the plasma samples taken from alleged casualties," the report said.
At the same time, OPCW experts said they had found traces of organic substances containing chlorine, allegedly used in the attack in Duma.
"Along with explosive residues, various chlorinated organic chemicals were found in samples from two sites, for which there is a full chain of custody," the FFM said.
The OPCW team carried out on-site visits to collect environmental samples and other evidence related to allegations of a chemical weapons attack by Syrian government forces.
The gas attack in Douma, which was filmed by the White Helmets last April, led to a series of airstrikes against Damascus, conducted by the US and its allies after Western countries accused the Syrian government of being behind the incident. Damascus denied the claims, calling them a "provocation." Moscow subsequently found victims of the alleged attack, who claimed that they had been forced to participate in the footage of the "attack" in exchange for food.
