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This question is a follow up of another thread, where we are discussing Theresa May's accusation of the Russian government which is supposedly behind the recent chemical attack in the UK.

Soon after the attack the UK implemented a chemical analysis which again supposedly shows that this compound can be produced by only one government in the world: the Russian government.

So, my question is, if the UK Chemical Weapons Institute can carry out such a chemical analysis and figure out what chemical weapon was used, does it mean that they themselves possess this technology?


On 14 March 2018, at UN Security Council Russia's representative Vasily Nebenzya claimed:

For the British specialists to be perfectly confident that this was a Novichok agent and not any other kind, they would need a control standard for proof. It [the substance used in the attack] must be compared to a control substance... They have a collection and they have the formula. In other words, if the UK is so firmly convinced this is Novichok, they have samples and formula and are capable of formulating it themselves.

Nebenzya in his speech refers to some professional chemist and I wonder what other professional chemists think of this.


Further reading:

  1. A BBC article explaining the Novichok agent; the Wikipedia page about the same as well
  2. Another BBC article detailing the timeline of political events.
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    $\begingroup$ The final proof of any structural determination is to make the compound and see if the properties are identical to the original. You can make a structral assignment and publish it without this final step. It happens all the time. I would expect that with the array of modern analytics tools avaible that they are pretty sure what the agent is, but this does not mean they have previously prepared it. $\endgroup$ – Waylander Mar 14 '18 at 15:23
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    $\begingroup$ Treaties don't prohibit the synthesis of chemical weapons, they prohibit their manufacture in quantity. And nerve agents are not particularly hard to make, just hard to handle. The word "produced" in the question creates ambiguity as what it really means is "produce on a large scale". Synthesising a small amount is something any chemist in a good lab could do, but it isn't the same as "producing" in the sense of the question. $\endgroup$ – matt_black Mar 14 '18 at 17:54
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    $\begingroup$ @matt_black More specifically, the Chemical Weapons convention (of which both Russia and the UK are signatories) requires any site making more than 100g of a Schedule 1 material (roughly, chemical weapons or chemicals whose only known use is making chemical weapons) to be reported to the OPCW. This does allow them to make small amounts for research into antidotes, detection, etc. $\endgroup$ – David Richerby Mar 15 '18 at 17:05
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    $\begingroup$ That would be a good and interesting question without the political fluff around it. Sure, it is there to give context, but it is absolutely unnecessary to talk about the chemistry issues involved. It doesn't even have anything to do with the nature of the compound. Have my down-vote. $\endgroup$ – Martin - マーチン Mar 19 '18 at 2:49
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    $\begingroup$ We've gotten a lot of flags on this and some of the other answers. I think that the political issues are strongly coupled to the question, and as such are difficult to factor out of the equation. That being said, please keep opinions to a minimum. Evaluating the science is okay, but evaluating the political motives is probably a slippery slope, and should be avoided if possible. $\endgroup$ – jonsca Mar 20 '18 at 0:15
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So, my question is, if the UK Chemical Weapons Institute can carry out such a chemical analysis and figure out what chemical weapon was used, does it mean that they themselves own this technology?

Ok, first.

Performing elemental chemical analysis does not give you a single idea if you can produce compound you analyzed. Knowing it structure does not guarantee this either. So, theoretically speaking the answer is no.

However, there are complications.

Novichok agent apparently belongs to the family of nerve agents that are toxic in extremely small concentration. Furthermore, they metabolize in the body, irreversibly binding to target proteins. Consequently, it is not likely to be possible to extract the toxic substance from the body, and to identify it one needs empirical data on the ways the compound is metabolized in the body (and even this does not give guarantees). This requires access to measurable quantities of the agent in question and a dedicated effort to study its effect.

Structures claimed to belong to Novichok agent family belong to a known family of fluorophosphate nerve agents. Methods for synthesis of this class of compounds are known, so producing some of the compound should be possible having only the structures themselves, even though the first approach might be needlessly costly.

That said, nerve agents have structures similar to some insecticides, that are produced in quantities. It should be assumed that any developed country with moderately advanced agrochemical industry can produce chemical warfare agents in military relevant quantities if needed. In fact, it is a common opinion that former USSR chemical industry was designed with this idea in mind.

THAT said, use of such exotic compound is idiotic on its own and thus unlikely. There are countless possibilities to produce strong toxins using freely available consumer chemicals only.

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    $\begingroup$ -1 for the detour into politics at the end. $\endgroup$ – David Richerby Mar 15 '18 at 12:18
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    $\begingroup$ I really wonder, why people down vote a detailed and informative answer, made by a professional. $\endgroup$ – Jacobian Mar 16 '18 at 6:19
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    $\begingroup$ @Jacobian I really wonder why people wonder why people downvoted, when they explicitly say why they did it. More constructively, without the last paragraph, I'd probably reverse my vote. $\endgroup$ – David Richerby Mar 16 '18 at 13:34
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    $\begingroup$ @David Richerby. permeakra explicitely said why he did it, though deleted his comment. Besides, the main value of the answer obviously is not in the last two paragraphs. $\endgroup$ – Jacobian Mar 16 '18 at 13:59
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    $\begingroup$ @DavidRicherby To my knowledge, nerve agents hydrolyze rather fast even in air and are fairly volatile in general. So I highly doubt they could. $\endgroup$ – permeakra Mar 21 '18 at 20:26
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No, the capability to identify a compound does not imply capability to synthesize that compound. Indeed, "analysis" and "synthesis" represent two branches of chemistry, and many chemists spend years trying to synthesize compounds of known structure.

Modern structure determination relies on roughly two steps. First is separation of sample mixtures into constituent parts, using various forms of chromatography. Next is analysis of chemical composition and bonding patterns using techniques such as IR spectroscopy and nuclear magnetic resonance spectroscopy, as well as mass spectrometry (MS), which weighs molecules (and their destructively ionized fragments) with extraordinary precision and dynamic range.

Advanced MS instruments can analyze very small amounts of collected samples, without special preparation, and at atmospheric pressure. Pure samples are not required for the instruments typically used in forensics and product testing (DART). When a pure sample is desired, one or more separation devices can feed the MS instrument in-line (LC-MS, GC-MS, MS-MS).

MS can measure molecular weight so precisely that the chemical formula can be deduced directly based on the fractional weights of the elements due to varying isotopic abundance. Often, a chemical formula is almost sufficient for unique identification. For example, the NIST Chemical WebBook contains only 4 entries with the same formula as the VX agent, all for VX or nearly identical compounds. The PubChem database contains only 1 (VX itself).

It is also possible to identify compounds using known chemical or physical interactions linked to a readout such as a color change. This principle is used in devices such as home pregnancy tests and lead test kits. The US military even has custom field test kits for some chemical weapons.

It should be noted that compounds introduced into an organism may be identified indirectly via metabolites found in blood or urine, even if the original compound is long gone. Again, VX agent is a suitable example.

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  • $\begingroup$ Technically one could argue that a home pregnancy test does not involve a chemical reaction, or at least not the making or breaking of chemical bonds; instead I believe it's usually a form of immunoassay where antibodies labelled with coloured particles are transported along a test strip by capillary action and captured by other antibodies immobilised on the strip (en.wikipedia.org/wiki/Lateral_flow_test). Otherwise, great answer. $\endgroup$ – nekomatic Mar 15 '18 at 10:34
  • $\begingroup$ >Advanced MS instruments can analyze very small amounts of collected samples, without special preparation, and at atmospheric pressure. || they do require a pure compound, though. $\endgroup$ – permeakra Mar 15 '18 at 17:47
  • $\begingroup$ >It should be noted that compounds introduced into an organism may be identified indirectly via metabolites found in blood or urine, even if the original compound is long gone | which, in turn, requires a prior empirical knowledge, i.e. a dedicated effort wih a compound obtained beforehand. Good luck with it. $\endgroup$ – permeakra Mar 15 '18 at 17:48
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    $\begingroup$ @nekomatic Thanks! I changed the wording a bit so as not to inadvertently exclude ELISA. $\endgroup$ – reve_etrange Mar 15 '18 at 18:15
  • $\begingroup$ @permeakra I think the theory is that the substance was administered through the ventilation system of Skripal's car. They could have obtained the pure compound from that. $\endgroup$ – David Richerby Mar 21 '18 at 14:13
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With any material (or device) there are three distinct steps necessary to make a copy :

  1. Be able to identify it by its behavior and interactions.
  2. Be able to determine its structure. Identification does not tell you something's structure, just its external behavior.
  3. Develop a process to construct the material or device as a prototype at least.

All that has been done in this case is step (1) and arguably (2). Step (3) is the biggie. It could take years or decades to develop the manufacturing process.

In the case of extremely hazardous materials step (3) is even more complex than usual, as even more care than usual has to be exercised to avoid potential accidents.

In some cases you may be able to skip step (2) and get step (3) completed first, but that doesn't mean step (3) gets any easier.

So, my question is, if the UK Chemical Weapons Institute can carry out such a chemical analysis and figure out what chemical weapon was used, does it mean that they themselves own this technology?

This is a weapon and as such they may not say that they can prepare it, but may be able to. They might even deny they can make it, but can. I've no particular knowledge about this specific substance in this regard.

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    $\begingroup$ Novichok agent apparently belongs to the family of fluorophosphates, just like VX and other nerve agents. There are reasonably well established synthetic methods for this kind of work, so 3) is fairly simple. Personally I have hard time with idea they were able to determine the agent. The extremely small amount of the agent means that there is no easy way to guess the exact structure of the agent. Guessing that it was a nerve agent is apparently simple, but finding exact structure is not. $\endgroup$ – permeakra Mar 15 '18 at 8:05
  • $\begingroup$ @permeakra. Thanks for this clarification! It would be great, if you make a full answer. $\endgroup$ – Jacobian Mar 15 '18 at 8:41
  • $\begingroup$ @permeakra There are a number of identifying techniques that require very little compound. You can do proton and carbon NMR at 600 MHz with under one mg. Less than 1 mg/ml concentration for mass spec as well, of course this is with some of the better instruments, but the UK government certainly has access to these. Even I had access to them back in university as a freshman even. Getting exact structure is less easy... , but you don't really need the exact structure to identify the agent, other similar structures may not be stable, etc.... so you can get a high confidence match. $\endgroup$ – ttbek Mar 15 '18 at 12:40
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    $\begingroup$ @ttbek That works only if you do elemental analysis or have a reasonably pure compound. Or, in case of chromatomass at least have the original compound present as free molecules in the solution. Identifying compounds that irreversibly bound to proteins is an entirely different thing, and if they are dispersed in the body fluids... no. $\endgroup$ – permeakra Mar 15 '18 at 12:43
  • $\begingroup$ @Chromato-mass in particular requires access to the source of the analyzed compound to obtain its mass-spectra beforehand. $\endgroup$ – permeakra Mar 15 '18 at 13:04
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Just chemistry here.

  • Chemists do not need to be already able to synthesize a molecule to identify it. All they need is a reference, either as physical sample or as collection of chemical and physical data. In both cases is irrelevant how these were obtained.

  • There is no way to identify the producer of an isolated molecule. Multidimensional analysis (normally it works for complex samples with an inherent geographical signature such as oils and wines, to give examples) OR considering "markers" such as impurities and byproducts can possibly point to a specific way of production/producer.

If one is able to identify a molecule or has enough references to it, then by replacing "one" with "a state, a government" it is surely possible to synthesis that idenfied molecule. It is just matter of effort, which can be big or relatively small.

There is not a straightforward "chemical" reason to trust one of the parts involved in the story.

I would also note that producing molecule X as chemical weapon (big scale, making enough heads, etc...) and synthesising X at common lab scale are two different things.

A state can be unable to produce a warfare agent but will be unfair to the chemists of that nationality to deduce that they cannot synthesise that specific molecule.

Edit: of course the total synthesis of certain complicated molecules, think of some natural products, can be a tremendous challenge. A nerve agent developed in the seventies or so does not certainly fall in this category.

See also a comment by Matt Black on the same line of the end of my A.

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  • $\begingroup$ You comment about multidimensional analysis is spot on, but you need to explain that a bit more. It only works if you can obtain a "reasonably pure" samples of the stuff being analyzed. A chemical weapon would leave on traces of itself and you'd never be able to obtain a "pure sample." So you'd never be able to use multidimensional analysis to prove who made a particular batch of the chemical. $\endgroup$ – MaxW Mar 21 '18 at 16:23
  • $\begingroup$ @MaxW the entire paragraph is meant to say that you cannot identify the producer of an isolated (isolated in synthetic chemistry sense) molecule The mentioning of multidimensional analysis and wines was to prevent debates. Obviously a chemical warfare agent extracted or recovered from a victim will be rather than impure too simple for multidimensional analysis. Thus I mentioned impurities They can be easily added as well. But my answer is general. Even in possession of a sample made by state X, you cannot claim X is the producer solely based on chemistry alone. $\endgroup$ – Alchimista Mar 21 '18 at 16:52
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There is really more than one question here: one is whether identifying a chemical requires the ability to make it; the other is whether the UK can reliably identify Russia as the manufacturer of the nerve agent.

The first question has a simple answer: there are plenty of known chemical structures that chemists don't know how to make, yet. This is common in natural products where chemicals are extracted from animals or plants and fully structurally characterised long before good mechanisms are found to synthesise them in a laboratory. So you don't need to be able to make something to know what it is.

But this is mostly irrelevant to the question of whether only the Russians can make Novichock agents. Not least because we know they have been made by others. But also because nerve agents are relatively simple chemicals and are easy to make (though not easy to make without killing everyone in the lab as a byproduct of the synthesis).

Chemical identification of a Novichock agent cannot possibly tell us where it was made: the chemistry can't tell us where the ingredients came from. The UK's portion down scientists have stuck to this line in statements.

This has led some to conclude that the evidence doesn't point to Russia. As does the fact that the alleged Russian work on the agents was never confirmed independently (other than the fact that others have confirmed that the recipes leaked by defectors actually work). But the allegation that this is some sort of false-flag conspiracy to damage Russia's image makes no sense. Firstly the development of nerve agents would be top secret and no government would blab about it in public. So we wouldn't expect the Russians to admit they had ever made or stockpiled the agents. Moreover, we would expect the western agencies to follow up the intelligence they had by both synthesising, testing and developing better ways to combat them. They wouldn't be doing their job if they hadn't. And we wouldn't be safe from hostile foreign powers.

So we should discount media simplifications that claim only the Russians could make them. But that isn't the point. We have good intelligence that they did research them and probably made stockpiles of them during the Cold War. So they have the expertise to handle them and use them. Some of the conspiracy theories allege that any competent chemist could have made them so why blame the Russians? But this ignores the issue of skill. Making a nerve agent isn't hard: not killing yourself in the process is very hard, deploying the agent is probably even harder. And it was the Russians who developed the agents and worked out how to deploy them. This matters, but conspiracy theorists have focussed on the ease of synthesis and ignored the extra expertise required to avoid death for all involved. They don't seem to understand chemistry: It takes large amounts of government investment to get that expertise.

So chemistry doesn't provide proof. But the chemical expertise to make and use the agents is held only by a very small number of players and the only one with a motive is Russia.

In short the key issue isn't chemistry but the expertise with particular chemicals. Plus the motivation to commit the act. The media should not claim that chemistry alone is definitive in fingering Russia, but the known-expertise plus history plus motivation makes a strong case.

Political appendix

Simple answers dealing with the chemistry out of context have already been widely appropriated to promulgate conspiracy theories about the Salisbury attack. Here is some of the context. Please ignore if you just want to stick with chemistry.

The real evidence that the Russians are the most likely suspect is a combination of the fact that they developed the agents (and therefore have the expertise required to work with them) plus the clear motivation they have to use them: it sends a strong signal that discourages defectors and opponents of the Russian government. They don't want to admit they did it but they want other defectors to know they did it. And they have form. A decade ago they used polonium 210 to kill another defector in London (unlike simple chemicals, polonium leaves a trace of radioactive debris that pointed very clearly to who used it as did the fact that only a very small number of countries can make it in the first place).

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    $\begingroup$ I think, Chemistry SE is not a good place for this kind of answer. 99% of what you are saying is about politics. But the question was asked with a clear idea to leave politics aside (just to avoid unnecessary debates). $\endgroup$ – Jacobian Mar 19 '18 at 18:22
  • $\begingroup$ @Jacobian I tried to put the key issues about chemical knowledge in context. Half the content is about what we can and cannot know based on chemistry and chemical expertise. The debate on this is full of selective quotation and misleading partial arguments so I put everything in context to avoid that possibility. $\endgroup$ – matt_black Mar 19 '18 at 18:33
  • $\begingroup$ Please see my comment under the question. Thanks! $\endgroup$ – jonsca Mar 20 '18 at 0:16

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