It is also part because of Theatre Crisis where many people died.
Hi Marakov, I would expect the reason the exact gas(aerosole) they used is so unclear is because the Russian government never 'unclassified' the operation. But from many (doctors ects), it was clear a fentanyl derivative was used. There is much speculation wiki claims it too be fentanyl, carfentanil or 3-methylfentanyl
"later conjectured to be weaponized fentanyl, into the theatre through the air conditioning system"
"Based on the gas' effects and examinations of victims, it appears to have been an FSB-made aerosol version of 3-methylfentanyl, an artificial, powerful opium-like substance. Government officials still treat its contents as a state secret."
http://en.wikipedia.org/wiki/Moscow_theater_hostage_crisisAlso there are many other claims;
"Allegedly, during the 2002 Moscow theater hostage crisis, the Russian military made use of an aerosol form of either carfentanil or another similar drug such as 3-methylfentanyl to subdue Chechen hostage takers. "
Unexpected "gas" casualties in Moscow: a medical toxicology perspective.Wax PM, Becker CE, Curry SC.
Ann Emerg Med. 2003 May;41(5):700-5.
http://web.jrc.ec.europa.eu/eis-chemrisks/toolbox/docs/terrrsdarticle.pdfBut I was watching this series years ago;
http://www.imdb.com/title/tt1112273/ In which they interviewed one of the special forces(spetsnaz) soldiers that was involved in the attack, and he gave what I would describe as the only believable account. The narrator asked him point blank what the gas used was. And he clearly replied "Sufenta" and it was in medical gas canisters, this guy was a soldier not a doctor or chemist so him knowing the exact trade name and how it is stored and used meant he had seen it and was familiar with it (and also would get into trouble considering it is still a Russian state secret he was revealing). It is the obvious choice as it is used widely in anesthesia, it also has a large therapeutic index and was available as an aerosole. It makes more sense than carfentanyl (unless the Russian military has tested aerosole carfentanil and kept it secret, but it is still not as suitable as sufentanil regarding therapeutic index and sufenta was available as a nasal aerosole at the time).
There is a lot of conjecture about exactly what was used because;
Fentanyl and most of its derivatives are highly lipid soluble and have large volumes of distribution. Many patients remained in intensive care units for several days after the exposure.
That is because patients were in intensive care up to 3 days after exposure, it could not have only been one of the short acting fentanyl analogs. But if you consider that an aerosole is not going give everyone a consistent dose (some will get much heavier doses depending on location), so considering some people got very heavy doses. The truth about the several day intensive care stay, would have been the results of an overdose of fentanyl type compounds;
We can only speculate that hypoxic brain injury, as well as delayed redistribution of the fentanyl derivative to the central compartment, may have contributed to prolonged hemodynamic and respiratory instability
For example with high doses of carfentanyl that have been treated with opiod antagonist (naloxone for example);
The narcotizing effects of carfentanil may recur 2 to 24 hours after treatment with an opioid antagonist. In an investigation on carfentanil in Rocky Mountain elk, high-dose naltrexone (100 or 500 mg of naltrexone per mg of carfentanil) was an effective antagonist; however, renarcotization at 8 to 24 hours was common when only 25 or 50 mg of naltrexone per mg carfentanil was
used.“Narcotic recycling” also occurred in carfentanil-immobilized wood bison that were treated with naloxone. Given the high lipophilicity of these fentanyl derivatives, redistribution from tissue stores to the central compartment may explain the recurrent opioid effect. Similar effects are known to occur with highdose fentanyl anesthesia and may be potentiated by acidosis, hypothermia, and rewarming
quotes from paper linked above
http://web.jrc.ec.europa.eu/eis-chemrisks/toolbox/docs/terrrsdarticle.pdf