Talk:Alleged Chemical Attack, August 21, 2013/U.N. Investigator Response/Report

Speculation

 * Exclusive: U.N. Report Will Point to Assad Regime in Massive Chemical Attack – Colum Lynch, Foreign Policy, September 11, 2013
 * ''U.N. inspectors have collected a "wealth" of evidence on the use of nerve agents that points to Syrian President Bashar al-Assad using chemical weapons against his own people, according to a senior Western official.


 * ''The inspection team, which is expected on Monday to present U.N. Secretary General Ban Ki-Moon with a highly anticipated report on a suspected Aug. 21 nerve agent attack in the suburbs of Damascus, will not directly accuse the Syrian regime of gassing its own people, according to three U.N.-based diplomats familiar with the investigation. But it will provide a strong circumstantial case -- based on an examination of spent rocket casings, ammunition, and laboratory tests of soil, blood, and urine samples -- that points strongly in the direction of Syrian government culpability.


 * UN report will confirm Syria chemical weapons use –AFP, Friday 13 Sep 2013
 * ''UN experts will confirm in a report to be released next week that chemical weapons were used in an attack near Damascus, UN leader Ban Ki-moon predicted Friday.


 * ''"I believe the report will be an overwhelming report that the chemical weapons was used," said Ban who also launched a new outspoken attack on Syria's President Bashar al-Assad.


 * ''Ban also gave a UN estimate that 1,400 people were killed in an August 21 attack which led to western threats of a military strike on Assad's forces.

It is very dangerous to say chemical weapons were used. They should stick to saying chemical agents or weapons grade chemical agents were used. The UN should not speak about weapons unless they can identify the delivery system with 100% certainty. If they just found sarin, then just as likely it could have been planted. If this was a false flag attack, it was done by a huge conspiracy with almost unlimited resources. The UN chemical experts just are not qualified to deal with it. They assume that people ("activists") are telling them the truth, when they should assume that everyone is lying to them. -- Petri Krohn (talk) 17:38, 13 September 2013 (UTC)
 * Thanks, Petri. I was about to bring a link to Lynch's article. It made me want to puke on Robert Menendez. Whether the official or the actual UN team is to blame, this is a horrible picture. They were "happy" with the amount of stuff they could point at "the regime" without explicitly pointing at them. A "nerve agent," can't tell which one, but from the finer points of that blank spot, you can see "the author." Very regimey characteristics, some Shia DNA, speaks Persian with a Russian accent, etc. --Caustic Logic (talk) 10:47, 14 September 2013 (UTC)


 * It seems possible this isn't even based on their work at all, but a way for some unnamed official to alert the inspectors what they're expected to find or say. You can say otherwise and get us grumpy with you for showing us wrong, or you can find a way to mumble something that sounds a bit like this. --Caustic Logic (talk) 11:00, 14 September 2013 (UTC)


 * Syria 'chemical weapons' crisis: LIVE UPDATES
 * Friday, September 13
 * ''17:35 GMT: Speaking by phone to AP from the Netherlands the head of the UN chemical weapons inspection team says he has completed his report on Syria and will deliver it to the UN Secretary General Ban Ki-Moon over the weekend.


 * ''"It’s done, but when to present it is up to the Secretary General," he said.


 * Preempting The Next Round of Lies Against Syria – Tony Cartalucci, September 14, 2013
 * What the UN report on Syria will say & what the liars in the West will claim it says.
 * ''Relying entirely on the momentum of its massive media networks and their ability to "will" reality into any shape they please, headlines such as "United Nations' Syria chemical weapons report "overwhelming," shamelessly attempt to link two out of context statements by UN Secretary General Ban Ki Moon regarding the Syria government's "crimes against humanity" and the confirmed use of chemical weapons in Damascus Syria, to place in the mind of readers assigned blame for the attacks.

Analysis of findings
The report was released on September 16, 2013. The pdf is here (3.5 MB).

At the beginning of the PDF we have three pages of Ban-Ki Moon intro and Sellström transmittal letter before the report starts. I suggest we use the page numbers of the PDF as reference, which will be three higher than printed on the report (but not the appendices) pages. --CE (talk) 23:56, 17 September 2013 (UTC)

At the moment the UN report is impossible to evaluate because no details are given of the lab tests on blood and urine samples. The environmental samples would have been easy to fake for insurgents with access to small quantities of "kitchen sarin". The blood samples would be more difficult to fake convincingly: in genuine victims examined at 7 days we'd expect to see that sarin metabolites are not detectable, that cholinesterase activity is markedly reduced and that (with a clever technique that splits sarin from its binding site), sarin could be identified as the molecule causing this reduced cholinesterase activity. In faked samples, cholinesterase activity would also be reduced (ex vivo effect) but sarin breakdown products would be present at unfeasibly high concentrations for 7 days post-exposure.

Let's hope that over the next few days people like Dan Kaszeta and academics who are working in this field will publicly demand more information from Sellstrom. --pmr9 (talk) 12:21, 19 September 2013 (UTC)

Symptoms and clinical signs
Why did so few patients report diarrhoea or have miosis? Eye inflammation is not a feature of sarin exposure. --Pmr9 (talk) 22:22, 17 September 2013 (UTC)

Dan Kaszeta has put some comments on the report on his website (http://strongpointsecurity.co.uk/site/wp-content/uploads/2013/09/D-Kaszeta-Comments-on-UN-Report.pdf). He notes that the history and signs are not consistent with what is known for sarin exposure. Miosis should have been detectable in severely affected patients even at 7 days. Patients reported having had convulsions without having had other symptoms such as vomiting and diarrhoea. 78% of patients reported loss of consciousness, which would usually be a terminal event in sarin poisoning. He asks "Is it possible that we are looking at exposure to multiple causes of injury? Were some of the examined victims exposed to other things in addition to Sarin?" --Pmr9 (talk) 09:35, 20 September 2013 (UTC)
 * "78% of patients reported loss of consciousness, which would usually be a terminal event in sarin poisoning." Definitely interesting. I have it downloaded now and read - excellent, recommended reading at a slim 7 pages. On that point, I do note there was a "sense of impending doom" also associated. One reading that some might go for is this: the sarin was supposed to kill them (as the doom proves) but Allah saved them (all but the 1,400) in a mass miracle. The revolution is blessed, but not so blessed as to threaten a serious crossing of that ol' red line and hopefully secure the next blessing in line. --Caustic Logic (talk) 09:25, 22 September 2013 (UTC)


 * Here's a major problem with the Sellstrom Report: for most of the symptoms reported, they don't tell you if the subject is experiencing the symptom during the examination or if the subject is telling the guy what symptoms he/she had on Aug21. OK, like, unconsciousness we can pretty well guess that was not being experienced at the time of the examination or the subject wouldn't be talking about anything.  So that must be a symptom on Aug21.  But the legend to the bar graph of symptoms on pg. 13 says "39% were confused or disoriented at the time of the assessment and that 14% had miosis".  Presumably that means: "14% had miosis, also at the time of assessment."  The writing in imprecise throughout.  So, although they don't have the good manners to tell us, Sellstrom et al. are apparently reporting those symptoms occurring on Aug21 and those occurring on Aug26, 28 or 29 all in one bag.  The low incidence of miosis relative to Tokyo (14% vs 99%) may be b/c in Tokyo they were counting wee pupils hours after the attack while in the Sellstrom Report they are counting them 6-9 days after the attack.--Pierpont (talk) 02:26, 14 October 2013 (UTC)


 * Would being confused or disoriented 6-9 days after the attack be a symptom of sarin poisoning? Or does this just mean the alleged victims were drugged before being presented to the UN?
 * Here is an alleged victim in Moadamiyah who is clearly mor then confused or disoriented
 * Man affected by Chemical Weapons attack on Damascus – ANAChannelEng, Aug 25, 2013
 * I think the video is a hoax. It seems the rebels have picked up two mute patients from some government-run mental institution and present them to journalists as sarin victims. Note the clean, identical hospital issue boxers the two men are wearing. I do not think these men came from some rebel field hospital in an area under siege where children are starving to death because the government does not let food in. -- Petri Krohn (talk) 20:40, 14 October 2013 (UTC)

Metabolites
The UN report states that "All biomedical samples were collected by local medical professionals under supervision of UN inspectors", but "the the assistance of local doctors and nurses ... reduced the time spent for collecting and labelling samples individually". In other words, there wasn't one on one supervision of the collection of blood samples.

Blood and urine samples were collected 5 days after the alleged incident in Moadamiyah and 7 days after the incident in Zamalka. The tests done on these samples are not stated: the results are just given as "positive" or "negative" for "Sarin and Sarin signatures" with no quantitation. In the environmental samples it looks as if mass spectrometry was used to measure sarin breakdown products, mainly isopropyl methylphosponate (IMPA and diisopropyl methylphosphonate (DIMP) and other "interesting chemicals"  As measurement of sarin metabolites is the only test that can be used in both blood and urine, I'm assuming that this was what the labs did and the comments below are based on this.

In animal studies the metabolites IMPA and DIMP have a half-life of about 45 minutes in plasma (http://www.ncbi.nlm.nih.gov/pubmed/18269798) (http://www.atsdr.cdc.gov/toxprofiles/tp119.pdf). Studies in human victims of the 1995 Tokyo sarin attack are consistent with this: plasma levels fell by half between 1.5 h and 2.5 h (http://www.ncbi.nlm.nih.gov/pubmed/9851684). The urinary half-life of sarin metabolites in rats is estimated as 3.7 hours, and elimination is complete by 2 days (http://www.nap.edu/openbook.php?record_id=9953&page=177). For biomarkers of sarin exposure several days after exposure, measuring inhibition of blood cholinesterases is more useful than measuring sarin metabolites (http://www.nap.edu/openbook.php?record_id=11064&page=28). In the Tokyo attack, this was detectable 3 weeks after exposure in individuals who had been symptomatic.

The UN report doesn't explain how (assuming that their test were based on sarin metabolites) these metabolites could have been detectable in plasma 5 to 7 days after exposure given their plasma half-life of 1 hour or less. Concentrations are not reported and the detection limit of the assay is not given. It would be usual for the lab to report this information. At the very least, we should be able to assess whether the measured levels are within the range compatible with recovery.

Possible explanations:

(1) More than 90% of the individuals studied had been exposed to sarin within the last two days, perhaps from contaminated clothes or skin, but this exposure did not cause symptoms.

(2) there was deliberate contamination of the blood and urine collection bottles (all hair samples were negative).

Pmr9 (talk) 22:22, 17 September 2013 (UTC) minor edits 18 September 20:13 UTC


 * Pmr9, thanks and welcome! That's fascinating stuff. I'm behind here and haven't looked into any of that, so ... I've been hearing the signs can be seen for up to six weeks, must be by the second method, "measuring inhibition of blood cholinesterases." But they used the first method even though it was days too late to turn up valid samples? I wonder why they would choose to even do that. If what you found is true, someone really needs to clarify and explain that to the world, that the investigators confirmed contamination or poisoning well after the alleged gas attack, and essentially proved a rebel frame-up. --Caustic Logic (talk) 23:33, 17 September 2013 (UTC)

Note: I think most of this should be moved eventually to a spot that doesn't exist yet. But this science is fascinating. I'm not real good with it, but ... Pmr9, I'm curious, is this something you know much about, just googling around, or somewhere between? Just googling around, I find hard-to-parse, jargon-laden sentences that seem to bear out what you're is saying. The abstract in the Tokyo attack doesn't mention hours, and I couldn't see where to read any further. --Caustic Logic (talk) 10:18, 18 September 2013 (UTC)

This PDF report about US military experiments that intentionally poisoned naval personnel with Sarin (p 7) says the slower metabolizing (-)-isomer of Sarin (the more harmful, they think) has a half-life of "several hours." From there one metabolite is DIMP, which the body rapidly turns to IMPA, and this is what turns up in the plasma of the Japan victims. If I follow... this means after that time, levels would be about half, the rest turned to DIMP and whatever else. The rest breaks dow, IIRC half the remaining half in the next x hours, half the remaining quarter in the next half-life, until basically zero. If we take a 5 hour half-life, It'll be to about 1/32 of the original amount within 24 hours, 1/256 in two days, probably undetectable after three, a fraction I shan't compute. But the last of the following processes might continue churning on a lower and lower level for ... a few more hours pas that, maybe? So what would they be seeing five and seven days after? Or alternately, what do we have wrong? --Caustic Logic (talk) 10:18, 18 September 2013 (UTC)

http://www.atsdr.cdc.gov/toxprofiles/tp119-c2.pdf (apparently related to a report above and possibly relevant, a gender difference in metabolism rates, in some species anyway):
 * A sex difference in the rate of conversion of DIMP to its primary metabolite was observed after intravenous administration of 14C-DIMP in rats (Bucci et al. 1992). The males appeared to convert DIMP to IMPA more actively than the females. The apparent plasma elimination half-life of DIMP was about 45 minutes in males and up to 250 minutes in females. Both the rate and total excretion of the administered dose in urine were also higher in male rats. However, this sex difference was not observed for orally-administered DIMP in minks (Bucci et al. 1992; Weiss et al. 1994).
 * By the way, just to be more sure, I think someone should try this on several varieties of rabbits, with a large pool of subjects from each, for greater statistical depth. Then also gophers, horses, and dolphins. You never know. --Caustic Logic (talk) 10:18, 18 September 2013 (UTC)

I hadn't come across the report on Project SHAD, and didn't realize there are two isomers of sarin with different half-lives. It looks as if this wasn't reported for sarin until 2000 (http://www.sciencedirect.com/science/article/pii/S0041008X00990604), so earlier studies didn't take it into account. Without special measures to separate the (-) isomer, sarin would be a 50/50 mixture of the two isomers. In the study by Spruit (2000) (Toxicology and Applied Pharmacology 169, 249 –254) the half-life of the slowly-eliminated (-) isomer in guinea-pigs is estimated as 58 minutes. The Project SHAD report states "Animal studies indicate that (-)-sarin is rapidly distributed throughout the body, within minutes, but eliminated very slowly with a half-life of several hours." No reference is given for the "several hours", and I can't find any other study than that by Spruit (2000). So we still have a working estimate for the total half-life of sarin and its metabolites in plasma as less than 2 hours, roughly consistent with values on the 3 individuals in Tokyo for whom blood samples were taken at 2 time points. We also have studies in both rats and Tokyo humans that indicate that sarin metabolites are not detectable in urine beyond 2 days after exposure. To illustrate what this means, assume an exponential decay curve with half-life of 4.8 hours. Plasma levels will fall 1000 fold in 2 days, and by a factor of one billion in six days. There has to be some other explanation for how these metabolites could be detected seven days after exposure. At the very least, one would have expected Sellstrom to comment on this remarkable finding. One possibility is that home-made sarin could contain some by-product that is stable and only slowly metabolized to IMPA and DIMP.

Disclaimer: my research is on metabolic biomarkers of disease risk in humans. I don't know anything about sarin beyond what I've read, and I have no experience of administering it to small furry animals. --pmr9 18 September 2013 14:20 UTC
 * "We also have studies in both rats and Tokyo humans that indicate that sarin metabolites are not detectable in urine beyond 2 days after exposure." This. I think. Augh, I need to just look closer t the report. Damn its non word-searchability. Sorry, I'll have more to say later. --Caustic Logic (talk) 11:12, 19 September 2013 (UTC)
 * On the disclaimer, not necessary, but thanks. :D --Caustic Logic (talk) 11:12, 19 September 2013 (UTC)

CL and pmr9, you guys are doing a great job. You sound like a couple of Harvard pharmacokineticists. Let me jump in with some general comments about half-lives of elimination. I've got an idea some of these basic pharmacology concepts are going to be important before this whole thing is resolved.

When a drug is being eliminated from an organism, the normal situation is that the capacity of the elimination system (usually renal or enzymes or both) far exceeds the amount of drug. In this situation, a constant PERCENT of the drug will be eliminated per unit time. This is called a 1st order kinetics situation. OTOH if the amount of drug saturates the elimination system, as with alcohol, then a constant MASS of drug is eliminated per unit time. This is called zero-order kinetics.

The term elimination half-life, or half-life, really only applies to 1st order, so that’s the first limiting assumption built into the term. If the kinetics are not 1st order, or if you don’t know what the kinetics are, or if there is more than one elimination process going on, a calculated or derived half-life can be bogus. This is a real problem w/ sarin.

In a 1st order system, if you plot the drug concentration vs. time, you get a pretty hyperbolic curve that reaches out to an asymptote concentration of 0 at some point in time. If you plot the ln of the drug concentration vs. time you get a straight line sloping downwards L to R. The slope of the line is the rate constant, k.  And ln(2)/k gives you the half life. Or, you can derive the half-life by inspection of the ln curve.

Once more – we are looking at the PERCENT loss per unit time, and the half-life is chosen arbitrarily as the time required to eliminate 50%. And that will be the same amount of time for the next 50%. So, as CL says, after the second half-life, you’re down to 25% etc. The rule of thumb is that after 5 half-lives there is not enough drug left to have an effect, pharmacologically. But with mass spec and such, the chemists can detect drug remaining in a system after a lot more half-lives than 5 -- practically out to that asymptote.

Also note that the half-life refers only to the target compound, not the metabolites. There is no necessary correlation between the half-life of, say, sarin, and the half-lives of its metabolites. Because the metabolite concentrations are increasing while the sarin concentrations are decreasing in the initial phase, often one has to mathematically tease apart the half-lives in a clinical situation. Experimentally, to find the half-life of the metabolite, you just pump the rat full of metabolite and measure the fall in concentration of that metabolite and not worry about how fast the precursor is being converted to the metabolite.

Another point, looking at a couple of those references pmr9 cites, is that when somebody pumps a load of radioactive sarin into a rat and then just follows the decrease of radioactivity in the animal or the increase of radioactivity in the pee, that will not give you a half-life of sarin. You will be looking at the effect of multiple, over-lapping elimination rates. With additional data you might be able to mathematically tease apart the various half-lives, but it would be a mistake to just take the half-life of elimination of the tritium or whatever and say that is the half-life of sarin.

The pharmacokinetics of sarin is also complicated because sarin binds to AChE and other esterases irreversibly. That means that before the bound sarin can be eliminated the AChE protein has to be degraded, and, of course, that takes time. And so, kinetically speaking, there are at least two pools of sarin. One pool is being degraded to its metabolites rapidly and washed through the kidney. It will have one half-life. The second pool is stuck onto the enzymes and is going to have a much longer half-life than the first pool. Whoever is reporting the data should specify how sarin is extracted so one can tell whether just free sarin is being measured or whether it’s total sarin. This talk is rough -- there may be 4 or 5 pools of sarin for all I know. I'm just trying to convey some of the complexity of this situation.

But, forgetting all these caveats for a moment, if you have some sort of ball-park number for the half-life of sarin in humans, and I’m not sure we do, then the UN data could be checked, which may be why they don’t give us the data. What I mean by "checked" is that if we knew the measured concentration of sarin in, say victim 34, at some time t, and we know the half-life of sarin, then we can back-calculate to get the concentration at 3am on the morning of Aug21. That calculation is (assuming 1st order kinetics and a single pool) –  concentration at t x 2^n –  where n is the number of half-lives between t and 3 am on Aug21. If that back-calculated concentration turns out to be gimongous, then you know somebody is punking somebody.

The UN has not released the actual concentrations in victims, and until it does so, the report has to be viewed with a lot of skepticism. I mean just the fact that they are not giving up the numbers they surely have is grounds for suspicion, IMO. I haven’t read the rest of this page yet, so I’m movin’ on to that. There's some good stuff here. --Pierpont (talk) 20:08, 24 September 2013 (UTC)

Testing for cholinesterase inhibition or sarin metabolites?

 * ''See also Talk:Alleged Chemical Attack, April 29, 2013

As Pmr9 stated above, "For biomarkers of sarin exposure several days after exposure, measuring inhibition of blood cholinesterases is more useful than measuring sarin metabolites " And he says it's not stated what method was used, so it could be that. If it was the other, that would mean they were exposed later than alleged. As interesting as that is, I suppose unless we can find something that rules it out, I'll presume they tested cholinesterases inhibition. Or rather, that's surely what they'd say if pressed by a real scientist, so we may as well presume for them that's their story, true or not. If not true, it'll be on us or whoever to show it. As a total noob to this science, I might be missing something, but that seems the right course for now (not that we have A single course or anything). --Caustic Logic (talk) 11:56, 20 September 2013 (UTC)


 * Cholinesterase inhibition is measured only in blood and it's not specific for sarin. Measurements would also need careful standardization against control individuals from the same population.  So as they tested blood and urine, and reported finding "signatures of sarin" it's reasonable to infer that they measured metabolites.  Dan Kaszeta also thinks this (see his comments linked above).  I don't think they can just bullshit if pressed further to explain what they did; there will be a chain of people from the technicians to the lab directors who can document what was done.  The directors of the four labs should have signed off on this report as it relies entirely on their work.  The way that the report is written with detailed description of field survey methodology and no information about the lab analyses suggests that the lab directors didn't get to see or comment on the draft.
 * --pmr9 (talk) 12:37, 20 September 2013 (UTC)


 * I know there's a wide correlation between what's in blood and what's in urine, but ... well, if that means a urine test can only be for the metabolites method, then it's true and that must be what they did. And that would be quite interesting. I just read Kaszeta's new report, and he bemoans the lack of specificity. He seems to feel it should have been matabolites tested for, as the clearest signs of Sarin in particular, but maybe they used the less specific AChe method. He "presumes" they used the former, but "perhaps" it was the latter. I'm attempting further contact with Mr. Kaszeta now. This is an issue I'll be asking about. Instead of further research, I'll hope for a response there and share what I can here. --Caustic Logic (talk) 11:21, 22 September 2013 (UTC)


 * The first report of lab tests for sarin in Syria that I can find was Fabius's statement on 4 June (http://basedoc.diplomatie.gouv.fr/vues/Kiosque/FranceDiplomatie/kiosque.php?fichier=bafr2013-06-05.html#Chapitre2) that "sarin residue in blood and urine samples taken from six victims [some apparently from Ghouta] proves beyond doubt that they were exposed to this gas". The samples were also analysed at the UK's Defence Science lab at Porton Down, where they were reported to have tested positive but the lab and the UK govermnet have refused to give any further details (http://www.rsc.org/chemistryworld/2013/06/french-sarin-detection-syria).  It looks as if the French lab and Porton Down are the two labs used by OPCW for biomedical sample analysis.  Government labs like Porton Down (under the UK ministry of defence) are of course harder to get information out of than university labs.


 * A quick update on the science. In the last 10 years or so new methods have been developed for detecting sarin exposure that can be used up to several weeks after exposure.  These methods work by detecting adducts of sarin with the enzyme BChE, or IMPA with albumin (the most abundant protein in blood).  These methods are used in blood: they wouldn't work in urine unless the patient had a disease causing protein to leak into urine.


 * Suppose that someone had access to kitchen sarin and wanted to contaminate blood and urine samples so that they'd give positive results. An amateur would just add kitchen sarin to the blood and urine collection tubes  This would give positive test results, but the giveaway would be the presence of free sarin (if the lab were suspicious enough to test for it) and unfeasibly high concentrations of free IMPA.  An expert who understood what the labs would be testing for would incubate kitchen sarin overnight with human albumin and human BChE (both commercially available), remove/separate the sarin and use the modified albumin and BChE to contaminate the blood collection tubes.  The urine tubes would be left alone, or contaminated only with traces of IMPA.  This would give test results exactly like real exposure, and it would require only a few mg of sarin and someone with graduate level biochemistry skills.  Even better would be to inject the "victims" with the modified albumin and BChE (after treatment with a decontaminating agent).  Injection-grade IMPA-albumin adduct could easily be prepared as IMPA, unlike sarin, is commercially available without restrictions.


 * Update: I hadn't come across this passage in a WSJ article of 25 August (http://wikileakssupportersforum.com/thread-570.html): "That winter, the Saudis also started trying to convince Western governments that Mr. Assad had crossed what President Barack Obama a year ago called a "red line": the use of chemical weapons. Arab diplomats say Saudi agents flew an injured Syrian to Britain, where tests showed sarin gas exposure.". If true, this would rule out contamination of the blood collection tube.  If the sample tested positive for IMPA-albumin adduct (Porton Down has published a paper on this method), then the only possible explanations are: exposure to sarin, exposure to IMPA, or injection with adduct.  --pmr9 (talk) 12:49 23 September 2013 (UTC)
 * Occam's razor does not apply to murder investigations. You must follow Holmes' advice: "How often have I said to you that when you have eliminated the impossible, whatever remains, however improbable, must be the truth?" -- Petri Krohn (talk) 14:25, 23 September 2013 (UTC)
 * To pmr9? Probably not often. Or is all that I/you stuff part of the quote? I don't know it well enough. Here, who knows, they could fly a guy all the way to London just to contaminate the tube, so they can say that's been eliminated because the guy was right there (see my comment below on Lockerbie). We've usually eliminated less possibilities than we think. I doubt Holmes could operate so well outside his set-up fictional universe. Right basic idea though. --Caustic Logic (talk) 09:30, 24 September 2013 (UTC)

I've focused on the lab tests because I think they're pivotal evidence. All other information about the 21 August incident is consistent with the hypothesis that there was no mass casualty event in Ghouta on 21 August, let alone one caused by large-scale release of sarin. But these 36 individuals interviewed describe losing most of their families to a gas attack, and their stories are apparently confirmed by the lab tests. --pmr9 (talk) 21:54 22 September 2013 (UTC)
 * From my study of the Lockerbie/Pan Am 103 investigation, I have little faith even in the hard science stuff like this. In 1989-91 investigators clearly planted all the crucial physical evidence, faked up lab test results and sloppy paper trails, deleted some witness statements and paid for others, etc. That was British scientists at RARDE and cops at different levels, compared to a U.N. investigation team selected by the OPCW (headed by a Turk who's the former envoy to both NATO and Israel), and I don't have a deep enough view of most investigations to say how widespread that kid of deceit is or isn't. And this ... well, it seems the most potential credible thing around, supposedly monitored for fairness, etc. and I can proceed as if these are the real results of whatever they tested. Supposed victims, collected by whoever (that process should get a section). Words out of mouths are nothing. But as you say, that it sort of matches blood work... that seems to lend it credibility and needs looked at like this. --Caustic Logic (talk) 09:30, 24 September 2013 (UTC)

Kaszeta E-Mail
I pitched a few questions to CRBN weapons expert Dan Kaszeta by e-mail. I don't see a single good spot to post all the answers, and some of the questions might be dumb enough and the answers thus useless enough I won't post them at all. Poor guy, I asked every one that popped into my head. Those relevant to this discussion - actually I guess this most of it right here and we'll call this the main posting. Q is me and A is Dan Kaszeta. --Caustic Logic (talk) 09:57, 24 September 2013 (UTC)
 * I just posted them all. --Caustic Logic (talk) 10:10, 24 September 2013 (UTC)

Q1 - You suggest testing for metabolites and I agree. But if they had done that, wouldn't a positive result on August 26 or 28 prove someone exposed them well after the alleged attack? That's what our rudimentary discussion has settled on, as I'm left presuming it was AChe inhibition they (would say they) tested. But I hope they also did that check, and eventually go public with the results if relevant.


 * A1 -  My earlier statements and papers on IMPA and MPA were limited by my lack of understanding of more recent techniques.   is a subject of open debate in academic literature how long IMPA and MPA last in blood.  It is a known fact that IMPA and MPA were found significantly post-exposure after the Tokyo incidents.   The UN team's samples were at the far end of the accepted envelope of time for IMPA.  You get a little more time for MPA, as it is the degradation product of IMPA.  After I wrote up my observations on the UN report, several scientists emailed me and made me much more familiar with more advanced techniques of post-exposure analysis.   The whole IMPA/MPA thing is the cutting edge of mid 1990s science (hence its use post-Tokyo) and additional techniques can be applied.  Much research has been done since that period of time.   It may be that the OPCW-network labs that did the tests on the blood used more advanced techniques.  Indeed, I am hoping they did.  I know these labs and they are cutting edge.   I'm not the greatest expert in the finer details, but these new techniques have to do with something called fluoride regeneration.  At least one article speaks of 56 day retrospective detection of Sarin.  I'm only able to read the abstracts of these articles online, but will try to summon them up when I get to the British LIbrary later this week, where I should be able to read the journal articles.   However until somebody authoritatively states what techniques were used for the UN report, we're outside the tent pissing into it, so to speak.

Q2 - If they only tested AChe inhibition, wouldn't that make other organophosphates, like Diisopropyl fluorophosphate, possible?


 * A2 - I would be a bit shocked if an AChE count was the only method they used for their conclusions.  AChe inhibition is by definition a general indicator of organophosphate (and indeed carbamate) exposure.  It should be noted that the environmental sampling part of the UN report is more clear about what they found. ''

Q3 - How long should GB, as detected by the mission in site samples, actually be detectable after the initial vapor evaporates? Can this even be from August 21 if coming up on the 26th and 28th?


 * A3 - Sarin in open air evaporates quickly.  Sarin exposed to moisture degrades quickly.  But Sarin can get itself trapped in places where it has no immediate path to open air and no immediate exposure to moisture and can last for a long time.  Sarin was found in Iraq many years after use by being trapped between the coating and metal of a munitions fragment.  I think that the places where the team found direct Sarin traces (as opposed to byproducts and decomposition products) are revelatory.  Nerve agents are known to absorb into soil, paint and metal, hence their potential to contaminate land and equipment, particularly the ones such as VX with lower vapor pressures and thicker consistencies.  The UN team found Sarin on metal fragments, a bolt from rocket head (bolt threads are a good place to look for hidden Sarin) and some window gaskets.  Plastics and some types of rubber can trap Sarin for much longer than it would last in open air.   A week is certainly feasible in that situation.  Months or years is possible on metal samples depending on the exact situation.  By the same token, Sarin was not directly found in some places - e.g. fabric samples, where I would expect it to easily evaporate.

Q4 - I wonder if dedicated pro-opposition partisans would allow themselves to be exposed to Sarin, or to another chemical that could test positive like it, lacing false witnesses to apparently prove their story. Considering the health effects of sub-lethal Sarin exposure, what would they risk?


 * A4 - I think this strains my credulity.  There is a razor's edge between a lethal and a sub-lethal dose of Sarin.  And we are talking about very small amounts to begin with.   It would be particularly difficult to deliberately calibrate and administer a sub-lethal dose by respiratory exposure except in the most highly refined and equipped test chamber in a laboratory.

Q5 -How helpful would it be if the report had specified what was tested, and had indicated degrees of poisoning?


 * A5 - In a word, very helpful.  I have some feelers out and maybe we can learn more about this valuable aspect of the investigation.

Q6 - Considering the likely role of opposition activists in the medical screening process, isn't it possible the sample was skewed? For example, any pro-government victims gassed by rebels but who survived might be filtered out somehow (bullets maybe),  while people spiked with traces of Sarin or DIFP/whatever, would be selected vs. people like the above?


 * A6 - My own opinion is that this is exceedingly improbable.  It presupposes access to some relatively exotic and rare chemicals and a level of expertise that is not otherwise in evidence.  The environmental evidence is very damning, and we don't yet know enough of the methodology behind the medical evidence to pass judgement on it.  As I said in an earlier answer, trying to mock up exposure to organophosphates, but just to the point of causing symptoms rather than death, is a razor's edge game and is playing with fire.  Certainly, if I was trying to fake the whole thing, I'd have done a far better job of it.  Why such a low level of miosis?  Certainly there are carbamate-based eye drops that  will pinpoint someone's pupils beautifully.  The unconventional breakdown of the signs and symptoms shows no attempt to mimic a classic sarin exposure.  Any cack-handed attempt to mock up the blood work would also probably lead to a more clear-cut presentation of signs and symptoms.  It's an interesting thought exercise: how to mock up just the blood work, but leave the symptoms unclear.  And why?


 * A6 - For what its worth, I think that the physical evidence couldn't have been easily mocked up.  However, I do not want to publicly state the exact reasons why I think that is the case because I don't want to give an easy script for someone who might want to mock it up.  The value of my statement would be worth a lot less than the value to a bad actor.


 * So he's leaning away from any kind of fakery by rebels, but notes that with the right script, they could. He doesn't want them to get any further ideas, but it could be too late and someone else already gave them that plus more. --Caustic Logic (talk) 10:10, 24 September 2013 (UTC)
 * I mean, as he says the signs didn't even come through, so if they tried to fake it they did bad. But they might have gotten the materials and adivce they needed to do whatever was done. I suspect they know all you have to do is show dead people not shot or stabbed, and also get the right samples in front of the right people, not necessarily all in one fell swoop. --Caustic Logic (talk) 13:14, 24 September 2013 (UTC)


 * Comments on Kaszeta discussion, and other points above. I'll focus first on the blood tests. I agree with Kaszeta that it would be difficult to fake positive blood tests by exposing volunteers to sublethal doses of sarin.  But there's no need to do this: the cutting-edge adduct-based blood tests that Kaszeta refers to could safely be faked by preparing adducts and injecting them.  Those receiving the injections might be told that they were therapeutic.  Protocols for preparing these adducts are described in the published papers (one from Porton Down) that used them to validate the adduct-based tests.  All you have to do is incubate IMPA with human albumin (for the IMPA-albumin adduct test) or sarin with human BChE (for the sarin-BChE adduct test).  The second test is more awkward to fake because it requires sarin (though only in minute quantities) and because the prepared adduct would have to be treated with something to remove the remaining sarin (but there is a standard reagent for this).  As it looks as if Porton Down is one of the labs used by OPCW, they've probably tested for the albumin-IMPA adduct.

In reponse to Petri's invocation of Sherlock Holmes, and assuming that the WSJ article I linked to above is correct in stating that a patient was brought to the UK last winter by Saudi intelligence to be tested positive for sarin, I think only two possible explanations now remain for the positive blood tests in samples from Syria.

(1) The Syrian army has been using sarin on a small scale since last winter without any noticeable military effect, but waited until UN inspectors arrived to investigate these attacks before launching a large-scale attack in eastern Damascus.

(2) An extensive deception operation has been mounted by Saudi intelligence, for which the initial target was not international media but the UK and French governments (someone in the UK government must have been sceptical enough to insist that the patient was brought to the UK for testing). This deception relied on being able to produce people who would test positive for sarin exposure, and later required enough sarin to contaminate at least one site. I agree with Petri that where an intelligence service in wartime is involved, an elaborate deception is entirely plausible (see Operation Mincemeat) and Occam's razor doesn't apply. So It's entirely plausible that Saudi intelligence would have access to someone with graduate-level biochemistry skills, and also have access to small quantities of sarin. But I agree with Dan Kaszeta: if they're that thorough why didn't they do a better job of faking the symptoms and signs? Maybe their clinical adviser should have read the Japanese papers more thoroughly. Unless you'd read these papers, it wouldn't have been obvious that miosis should persist a week after exposure even in those treated with atropine.

--pmr9 (talk) 22:44, 24 September 2013 (UTC)


 * I'm confused / sceptical about the Kastenza statement that the gap between detectable and lethal doses is extremely narrow.


 * The per-cutaneous LD50 in a 70 kg man is 1.7 grams. Riegel ReportIt doesn't seem at all implausible for milligram to microgram doses to be given to stimulate symptoms and produce byproducts.


 * To be brutally frank, if there was an accidental death or two doing this I doubt the hoaxers would care in the least

--DEADBEEF (talk) 01:09, 2 October 2013 (UTC)


 * I agree it's not so risky to expose volunteers to sarin under controlled conditions. This poster (www.lancaster.ac.uk/shm/med/chicas/research_posters/ISEE2009.pptx)  describes exposure of 2980 UK servicemen to sarin at Porton Down up to 1987.  In most of them the dose was enough to reduce red cell cholinesterase activity by more than half.  There was only one death (in 1953, covered up for 50 years).


 * But there'd be no need to do this unless you were trying to fake the sarin-BChE adduct test and you had no access to a lab to prepare the adduct for injection. The IMPA-albumin adduct test used at Porton down could be faked just by swallowing some IMPA (non-toxic).  ---Pmr9 (talk) 09:11, 2 October 2013 (UTC)


 * Thanks for that, both. I was not really satisfied with that answer. For example, he said " It would be particularly difficult to deliberately calibrate and administer a sub-lethal dose by respiratory exposure except in the most highly refined and equipped test chamber in a laboratory." Well, maybe I meant by some other method. And also, I was asked about "another chemical that could test positive like (Sarin)," like IMPA, and this wasn't addressed. It was just Sarin, hard to fake without death, (although I was asking about volunteers, I specified "dedicated"). He's leaping to extremes from which it can be dismissed with a flick of the wrist. But while he's sure it's there, Sarin is still hard to match with the symptoms reported and seen on video, unless you propose some random chemical cocktail to make it all fit. It seems that's what Kaszeta is working on now. I look forward to the mental gymnastics. --Caustic Logic (talk) 09:24, 2 October 2013 (UTC)

Additional note: The sodium salt of IMPA is a white powder, for which the median lethal dose in an adult human (extrapolated from rats) would be about 500 g (www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA107574‎). To fake exposure to a sublethal dose of sarin, you'd have to swallow 1-2 mg which should be safe as it's less than 1/100,000 of a lethal dose. This would give positive tests for IMPA in urine for about 2 days, and positive blood tests for IMPA-albumin adduct for about 4 weeks. ---Pmr9 (talk) 20:37, 3 October 2013 (UTC)
 * 7650 mg/kg is as toxic or less toxic than sugar, table salt or alcohol. -- Petri Krohn (talk) 06:25, 4 October 2013 (UTC)


 * Oh shit! Only made number 8 position in the all time high list for non-lethality. I bet it was the sodium that killed them rats! -- Petri Krohn (talk) 07:10, 4 October 2013 (UTC)

Summary and conclusions from combining all information about blood and urine tests for sarin from Syria
I'll try to draw together what we know from combining the UN report with earlier reports of blood/urine test results specifically those from the 29 April Saraqeb incident


 * 1. Since last winter there has been an operation involving Saudi and perhaps also French intelligence to use blood/urine tests to convince western governments that sarin is being used by the regime. This started with bringing a patient to the UK for testing, and continued with shipping samples from Jobar and Saraqeb to France in April.


 * 2. We have very little information about what tests were done. Urine tests must have been for free IMPA. For blood, we know that Porton Down uses the IMPA-albumin adduct test, and Le Monde reports that the Le Bouchet lab used a test for "regenerated sarin" - presumably sarin-BChE adduct - on two samples from Saraqeb.  We don't know anything about the tests done for the UN report or even what labs were used.


 * 3. Two odd features of the results reported so far: the level of 9.5 ng/ml reported for "regenerated sarin" in the Bouchet lab implies a massive and lethal dose; and in the Ghouta incident one would not expect positive tests for IMPA at 7 days after exposure


 * 4. The IMPA and IMPA-albumin adduct tests are easy to fake for large numbers of people using IMPA given by mouth.


 * 5. The sarin-BChE adduct test could be faked with access to sarin and to human recombinant BChE (rBChE) To contaminate blood collection bottles you would need only tens of microgrammes of rBChE: easily available as a lab reagent.


 * 6. To prepare sarin-BChE adduct for injection into more than one or two people you would need hundreds of milligrammes of rBChE. As far as I can tell only two small companies in the US are able to produce rBChE on this scale, and it would be hard to buy such large quantities discreetly (they'd want to be satisfied that you weren't infringing their IP on therapeutic use).  Maybe easier to just expose people to sarin under medical supervision.

If the tests were faked, dosage inconsistencies would probably give this away if detailed results were available. For instance we'd find that back calculation of the dose was not consistent with the clinical features. Use of rBChE could be detected by measuring the glycosylation (attachment of sugar molecules) of the protein. ---Pmr9 (talk) 23:03, 6 October 2013 (UTC)

Hair samples
As Pmr9 notes above, all hair samples were tested negative for Sarin (page 18). On page 16 we learn that there have been three hair samples, two from Moadamiyah and one from Zamalka. In the tables in the Appendix, what I can find are four hair samples, tested negative, and resulting from August 25 (page 37). Apparently those are control samples, maybe from the team. --CE (talk) 23:56, 17 September 2013 (UTC)
 * odd, they mention the three hair samples being negative, but those don't seem to appear in the charts. As you say, there are four hairs listed, apparently controls, taken before any field visit. Blood (plasma) and urine samples are listed in the later charts subject-by-subject, but perhaps just because it would be such an un-used column, hair isn't there. As for the negative, may not mean much. I looked into it. This hair site says normal growth rate is 1.25 cm per month. That would be about 0.25 cm in the app. 6-day span involved. Not much. this commercial site sells drug testing services, and they say drugs will appear after the hair has enough time to grow out: 7-10 days. At five and seven days, nothing should be expected to show up, even if they were poisoned. --Caustic Logic (talk) 09:17, 18 September 2013 (UTC)


 * Yeah, but shouldn't the hair be contaminated in the first place? Wasn't that even an argument of one of the experts saying it might not be Sarin, that the people treating the victims without proper protection would get affected themselves because the stuff concentrates in hair and clothes? Well, I don't know. Just an observation. I think we can at least conclude that the charts aren't complete. --CE (talk) 14:55, 18 September 2013 (UTC)
 * Contaminated like everything but washed, etc. It's the biological indicators you get from the hair tissue that last. I think that's why they do it. Best for things over the last months and years, but not so good for earlier this week. --Caustic Logic (talk) 11:02, 19 September 2013 (UTC)

Dan Kaszeta

 * Observations on the United Nation Report released 16 September 2013 – Dan Kaszeta, 19 September 2013

This is a brief, readable report, based on solid knowledge and skepticism. There's no good reason not to read this. Some good quotes below. --Caustic Logic (talk) 09:32, 23 September 2013 (UTC)
 * My previous skepticism on the use of Sarin was based on video evidence and interpretation of signs and symptoms of exposure...
 * Denis O'Brien, Pascal Zanders, and others have seen and said the same thing. Apparently someone in the area has blood that tests as if touched by Sarin, but that seems to have little to do with the masses of struggling and dead people we saw on August 21. --Caustic Logic (talk) 09:32, 23 September 2013 (UTC)


 * By definition, dead people cannot be interviewed.  Since Sarin is highly lethal, the people with the most severe signs and symptoms are unavailable for interview.


 * Is it possible that we are looking at exposure to multiple causes of injury? Were some of the examined victims exposed to other things in addition to Sarin?


 * Since a direct test for Sarin is unlikely to have been useful, I really wish that the report would specify how the blood and urine samples were actually tested. Presumably, the OPCW labs tested for biomarkers such as IMPA and methylphosphonic acid (MPA) ... a very clear indication of Sarin exposure. ... Or perhaps they tested for acetylcholinesterase (AChe) inhibition.  AChe levels would be an indicator of exposure to toxic organophosphorous compounds (which include, but are not limited to the nerve agents) or carbamates, a chemical family which also includes some medicines and some pesticides. Since the environmental samples were analyzed quite closely for MPA, IMPA, and related compounds, I presume that the blood testing did so as well.  But I feel that the report should have been specific in this regard.  If IMPA was detected in blood samples, that is as equally compelling as evidence as the environmental samples.


 * Loss of consciousness: Generally, loss of consciousness is considered to be a very grave sign in nerve agent poisoning, happening shortly before death. How is it 78% of the patients had lost consciousness? The sample victims include at least two patients (patients SN 32 and 34) with positive blood results, but no other distinctive nerve signs or symptoms.

Dr. Abbas Foroutan
Sharmine Narwani has published comments by Dr. Abbas Foroutan from Iran.
 * CW Expert Opinion on the UN Report on Syria – Sharmine Narwani, Oct 1 2013 (nsnbc, Global Research)
 * ''Upon our request, Dr. Foroutan reviewed the UN Report on Syria and provided us with some critical insights, addressing the issues of environmental and human sampling conducted by the UN investigators in Ghouta.

Oksana vs. Angela

 * 'No sarin detected in West Ghouta environment, only in human samples' - UN's Angela Kane, RT, October 3, 2013
 * Oksana Boyko seems to have been reporting on the ground while the investigation happened so this is a very informed discussion. Some WTF moments. Angela is Kane keen to assure that no death toll numbers are approved by the UN. And they didn't look at dead bodies because they can't talk. So why ask? Really. --CE (talk) 01:24, 4 October 2013 (UTC)
 * Why ask? – Well, they could at least asked the rebels to show them the mass grave sites. But then again, the UN, or who ever, would have clearly seen them from satellite images – if there were any – and HRW would have come screaming with their new evidence. -- Petri Krohn (talk) 05:59, 4 October 2013 (UTC)
 * P.S. – Interesting to see that the August 21 "attack" is now known as the Goutha incident. -- Petri Krohn (talk) 06:03, 4 October 2013 (UTC)

More on the interview here: Angela Kane succeeds in sounding like an idiot.
 * Saudi black op team behind Damascus chem weapons attack – diplomatic sources – RT, October 04, 2013
 * ''“Dead body can’t tell you anything. The dead body can’t tell how the person dies, how the person was affected, how the person suffered. A living person can tell you that,” Kane said.

I would argue that the exact opposite is true. If she thinks that someone in Syria is telling the truth, then she is not up to her job. -- Petri Krohn (talk) 20:12, 4 October 2013 (UTC)


 * I was surprised to find that Angela Kane is a German. Her wikipedia article states that she spent the years 1995 to 1999 developing the UN website. If you ever tried to find something there, I don't have to tell you how evil she must be... ;o) --CE (talk) 23:29, 6 October 2013 (UTC)


 * Mildy off-topic but this interview Boyko did with Peter Maurer, the president of the international committee of the Red Cross, is well worth listening to. --CE (talk) 01:49, 16 October 2013 (UTC)

Denis O'Brien
I tried to do a comprehensive analysis of this Sellstrom Report but had to give up at 24 pages -- I was beginning to get miosis myself. One of the most frustrating documents I have ever tried to work my way through and I have reviewed (and rejected) my share of piss poor scientific papers in my day. If I had seen Boyko's take down of Angela Kane first, I might have save myself the frustration. Boyko said most of what needed to be said. She was brilliant, and her RT follow-up was even better. Pigeon Poop on the Pump Handle: A Critique of the Report of the UN Mission to Investigate the Use of Sarin in Damascus--Pierpont (talk) 02:09, 14 October 2013 (UTC)
 * So to be clear then you are Denis. I knew that, of course, but I don't think everyone did. Just as we all had good stuff to add the site was down, but now that it's back (is it working better than ever?) we're getting back on board, not scattered on the waves. This, thank you for the work. Whether it was a bit too much or too little work is less important - it's the type and spirit that matters. I love the introduction,one can tell you really care. That's all I read yet, page one. --Caustic Logic (talk) 02:37, 14 October 2013 (UTC)
 * It stays good. Sharpened critique with hilarious delivery. Felt a bit guilty for laughing so often as it is such a gruesome topic. *points at Assad with rocket motor* This should be read by the people who parroted the talking points all over the place, they could actually learn something about science. Thanks for caring Denis, as you say the victims and also the team on the ground deserved better. btw, in case it went under, take a look at my little youtube collection I dubbed the Firas Tour to see just HOW closely they were led, at least on the trip on the 28th. --CE (talk) 07:28, 14 October 2013 (UTC)
 * CE do the UN Mission videos allow one to tell where the teams were on each of Aug28 and 29? Sellstrom doesn't say. We know where they were on Aug26.--Pierpont (talk) 02:03, 17 October 2013 (UTC)
 * The place where they take rocket remains samples on August 28 has been geolocated, I don't know about the other stations of the "Firas Tour". I don't think anybody has tried it with the August 29 tour, but should be possible. Here is a video playlist. The "citizen journalist" in video 12 has been seen at other interesting locations and together with Liwa al-Islam leader Zahran Alloush. --CE (talk) 09:25, 17 October 2013 (UTC)

No sarin in Moadamiyah?
There is much speculation about the environmental samples not showing traces of sarin in Moadamiyah, while the "patients" tested positive for something. Moon of Alabama may have been the first to point out the discrepancy. The same argument was made by Sharmine Narwani and Radwan Mortada: A follow up with much discussion is posted by Qifa Nabki: The discussion is worth reading. PMR9 is one the people commenting. -- Petri Krohn (talk) 22:55, 24 September 2013 (UTC)
 * Syria: NYT, HRW Wrong To Claim Chemical Attack Origin – Moon of Alabama, September 18, 2013
 * Questions Plague UN Report on Syria – Sharmine Narwani and Radwan Mortada, al-Akhbar, September 23, 2013
 * Degrading Discourse – Qifa Nabki, September 24, 2013

I´m wondering what happened to all that "gassed kiddies" in the clips from the opposition: Were they buried immediately, or kept in the morgue to be indentified by their relatives, and were there any samples taken from them? -- Jim Jekyll (talk) 12:23, 5 October 2013 (UTC)
 * We're all left wondering. Blood was taken, they haven't been seen rotting unburied anywhere. It's said there was lots of burial -it continued at least 18 hours in Zamalka, Reuters heard from locals (Ghouta Residents Cope With Aftermath Of Syria Chemical Attack). We don't get to see that, nor the streets so packed with bodies you couldn't step on one, nor the homes where they found a whole family huddled in the bathroom, etc. Video silence for almost all of this. This is an off-topic corner, so I'll cite it for the next thing in the right section, if I can now. --Caustic Logic (talk) 00:17, 6 October 2013 (UTC)

Okay, here's a thought exercise. There is one lab saying one spot had traces, so let's say this site and shells originally did have as much Sarin (or impersonating derivatives) as the others did (by delivery or by hand-held sprayer), and that's the last bit to remain. True, it's earlier, but maybe the lesser original amount and here's the main thing, geography differences. Note that NW of Damascus is that serious ridge of mountains, which M. al-Sham is nestled against, while the other areas are in a flatter area with some intervening city and topography. This could be enough difference to channel hot desert winds across the one and not the others. And from what I gather of liquid Sarin, it behaves about like water. So potentially, not the crucial point it seems. --Caustic Logic (talk) 12:34, 6 October 2013 (UTC)

And then a different thought: in the growing allegations of "regime" embargo and siege of Ghouta, Moadamiya is repeatedly singled out as the tightest-squeezed, with the increasing cases of children starving clear to death in front of rebel cameras (the cameramen and rebels seem to be eating enough, FWIW). Anyway, there's a real siege and shelling and I imagine there must be some kind of blockade that's working, that they're pissed about and want broken. Maybe not getting their Sarin sprayer smuggled in quick enough to make the environment match their victims is what triggered this baby-starving episode! --Caustic Logic (talk) 12:34, 6 October 2013 (UTC)