ROBERT SIEGEL, HOST:
Members of the U.N. Security Council were stunned watching a video shown yesterday by a Syrian doctor. It purports to show children dying from a chlorine gas attack in the town of Sarmin, an Idlib province. Here's the U.S. ambassador to the United Nations, Samantha Power, after seeing the doctor's presentation.
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SAMANTHA POWER: The video in particular of the attempts to resuscitate the children, I don't - I mean, if there was a dry eye in the room, I didn't see it.
SIEGEL: The Organisation for the Prohibition of Chemical Weapons says that chlorine is delivered in barrel bombs dropped from helicopters. It's widely believed that pro-Assad regime forces have the arsenal and the aircraft to do that. For more on the effects of chlorine gas and how it evidently remains on the battlefield despite Syria's agreement to dispose of its chemical weapons, we turn now to chemical weapons expert Amy Smithson. Thanks for joining us once again.
AMY SMITHSON: My pleasure to be with you.
SIEGEL: And, first, what does chlorine gas do to its victims?
SMITHSON: Well, chlorine will cause you to cough and have respiratory difficulties if you inhale it. And it can release fluid into the lungs. It's kind of like drowning on dry land. It's a horrible, horrible way to die.
SIEGEL: But it is very often lethal when used, you're saying?
SMITHSON: It can be lethal if enough is inhaled. But this is a commercial chemical that has many constructive uses - for example, water purification. And unfortunately we are now approaching the 100th anniversary of when chlorine was introduced as a weapon of war in World War I battlefields.
SIEGEL: But back in 2013 when Syria agreed to relinquish its chemical weapons, the public discussion was very much about mustard gas and serine gas. Did the Syrians somehow manage to get chlorine gas exempted from that agreement or did they just not observe the agreement?
SMITHSON: The Syrians relinquished what they declared as chemicals that they acquired for weapons purposes. But the way that the treaty works is that inspectors are supposed to go to their industrial sites and make sure that chemicals are not being diverted from those sites that would normally be used for standard purposes like, as I mentioned, water purification.
SIEGEL: Are you in any doubt that in the Syrian War it would be the Armed Forces or its allies - not the rebels they're fighting against - who would most likely have used chlorine gas?
SMITHSON: Both Human Rights Watch and the Organisation for the Prohibition of Chemical Weapons have presented strong evidence that chlorine is being delivered from helicopters, and the only combatant in this conflict that has helicopters is the Syrian government. So I have absolutely no doubt who's behind this.
SIEGEL: Given what's happening in Syria these days, it seems unrealistic to think that inspectors would be visiting chemical plants, wherever they might be. Is this a flaw in the treaty - that it would require inspections during wartime in hostile areas in order to enforce a provision like keeping chlorine off the battlefield?
SMITHSON: When the Syrian government joined the Chemical Weapons Convention, it is the first time in history that a government has agreed to give up a weapon of mass destruction in the midst of a conflict. I do not believe that the Syrian government has fully declared everything that it has - for example, some delivery systems and perhaps quantities of ricin, which is both a chemical and a biological agent. So there are going to be problems along the way, including getting inspectors in for routine inspections of commercial sites in Syria in the midst of a conflict.
SIEGEL: Amy Smithson, thanks for talking with us once again.
SMITHSON: My pleasure.
SIEGEL: Amy Smithson, chemical weapons expert, speaking to us about news of a suspected chlorine attack in Syria last month. Transcript provided by NPR, Copyright NPR.