UN tests expected to show nerve gas sarin used in Syria chemical attacks

A photo taken by a Syrian citizen journalist shows a U.N. weapons inspector collecting samples at Ain Terma, near Damascus, on Aug. 28. EPA

The results of testing of blood and environmental samples gathered by U.N. inspectors after last month’s suspected chemical weapons attack in Syria will be released as early as Monday, and are expected to show that sarin gas was used, U.S. officials told NBC News on Thursday

"We'd be surprised if it doesn't" (show the presence of sarin), said one official, who like the others spoke on condition of anonymity.

The samples were gathered by inspectors from the Organization for the Prohibition of Chemical Weapons (OPCW), operating under the auspices of the U.N., days after the Aug. 21 attacks on rebel-held enclaves in the Ghouta district outside Damascus. The U.S. has blamed Syrian President Bashar Assad’s government for the attack on Ghouta, which it says killed 1,429 people – many of them women and children.

After the OPCW team left Syria, the samples were sent to two unidentified European labs on Sept. 4. The labs had until Sept. 19 to deliver their findings to the office of U.N. Secretary Ban Ki-moon, but were running ahead of the deadline, the U.S. officials said.

A spokesman for the office of U.N. Secretary General Ban Ki-moon told NBC News that the reports will be communicated to the U.N. Security Council and member states as soon as they are received.

One U.S. official said the findings are expected to put the Aug. 21 attack in the context of other suspected chemical weapons attacks carried out by the Assad regime dating back approximately a year.

The mandate of the OPCW, the agency responsible for enforcing the Chemical Weapons Convention, is determining whether chemical weapons were used, not who was responsible for the attack.

The reports from the two labs must agree for there to be a conclusive finding. The reports also must meet both scientific and legal standards, since a chemical weapons is a war crime under both the Chemical Weapons Convention and the Geneva Convention. Any criminal prosecution would be led by the International Criminal Court. 

Sarin, a colorless, odorless gas, can be deadly even at very low concentrations, suffocating victims by paralyzing their lung muscles. Victims who absorb non-lethal amounts may suffer permanent neurological damage.

U.S. President Barack Obama threatened to launch a retaliatory military strike against the Syrian forces over the use of the banned weapons, but has delayed any action to consult with Congress and pursue a diplomatic solution. 

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