Busted, Decisively

"I mentioned that my wife and I were planning to do some experiments to verify one odd claim made by a certain IVAW member, one Jennifer Sprager, that she poisoned detainees by putting MRE heater material into cigarettes.First reported here in the local press, this was repeated over at Obiter Dictum.Parts of her story have already been debunked by Chickenhawk Express. But I was curious about the MRE heater question. For those playing the Home Game, MREs come with a heater package consisting of a light green plastic bag with a package of some sort of stiff fabric containing a gray powder. You rip open the bag, shove a sealed package of food inside, and add water. The powder reacts to the water and heats up, giving of foul-smelling vapors in the process which you aren't supposed to sniff as they displace oxygen, although they are harmless enough in and of themselves."
The Marching Camp

And "you" said this stuff would have no value