FILE - This Aug. 25, 2013 file photo shows black columns of smoke rising from heavy shelling in the Jobar neighborhood in East of Damascus, Syria. The Obama administration is sure about one thing: Syrian President Bashar Assad�s regime must be punished after allegedly using deadly chemical weapons, possibly including sarin gas, to kill hundreds of its own people. U.S. and allies accuse Assad of crossing the red line that President Barack Obama said would have �enormous consequences.� That is now expected to trigger a military strike, limited both in time and scope, with the goal of downgrading and weakening Assad's regime _ but not topple him or destroy his forces. (AP Photo/Hassan Ammar, File)
WASHINGTON (AP) — Three simple numbers will prove whether sarin was used to gas Syrians last month: 99-125-81.
Chemists this week around Europe are feeding samples of bodily tissue and dirt collected after chemical attacks in Syria into sophisticated machines. They are waiting for those three numbers to read out in a bar graph on a computer screen. Carlos Fraga, a chemist who specializes in nerve agent forensics at the Pacific Northwest National Laboratory in Richland, Wash., calls those numbers sarin's fingerprint.
Fraga says once chemists see those digits, they know they've got sarin. But he and other experts say it will probably take about two weeks for scientists to retest, confirm and write up reports.
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