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Frequently Asked Questions -- Salisbury poisoning incident (all external links will open in a new window)

These FAQs will be updated from time to time by Richard Guthrie. Happy to receive feedback or suggestions for more topics to be covered. The first iteration of this page was published on Sunday 18 March 2018. Last update Friday 13 July 2018, 20.45. Original answers are preserved with additions and updates clearly indicated to allow readers to see how available information and understandings developed.

It is worth noting that there are clearly puzzling and contradictory aspects to this case. This is why there is a need to keep a watching brief on this while there is still much more to understand. As more information becomes available, some aspects will become clearer.

Overarching Questions

Is the evidence that the Novichok material used in Salisbury came from Russia strong? Yes, very strong evidence, but what has been made public is not yet to the level of proof that would be required by a court. However, the investigation is ongoing and more evidence may be gathered.

Shouldn't the Russians be treated as innocent until proven guilty? There have been a range of deception actions by the Russians over the last 25 years or so over the Novichok programme. They have been under a legal obligation to declare the programme under the Chemical Weapons Convention but have never done so. There are few sources for the material(s) used in Salisbury and it is right that Russia is asked to account for their material.

Is the taking of the allegation that it was the Russians to the Security Council premature? Hard to tell. The use of such a poison was a brutal act that cannot go unresponded to. To pause too long would weaken the taboo against the use of poisons as weapons. It is clear from the Litvinenko case that senior Russian authorities have been involved in earlier assassination activities on UK soil.

Is this a repeat of certain western governments' assessment of Iraq in 2002-03? No. The science is robust. The Novichoks issues have been ongoing since the first revelations in the 1990s. While there is much unconfirmed information that has never been possible to independently assess, there is enough confirmed information to be confident that such a programme did exist, even if there is a vagueness about what the absolute scale was.

The Salisbury poisoning

How were the Skripals poisoned? The information made public indicates that the Skripals were exposed to a nerve agent. For a poison like this to work it must get into the body. The basic routes are injection (directly into the body), breathing it in (inhalation), eating/drinking it (ingestion) or by getting it on the skin (contact). On the information made public so far, the most likely route would be as a contact poison. Some past nerve agent formulations have been created to stick to surfaces to act as a contact poison. Some contact poison formulations have also been designed to take time to cross the skin barrier to get into the body, meaning that poisoning symptoms do not appear for some hours. By its nature, a contact poison can lead to cross-contamination as poisonous material that is transferred to a human hand, say, from the object that has been laced can then be deposited on another surface when the hand touches it. This would explain the presence of contamination on the table in the restaurant, for example.

What does a nerve agent do? Nerve agents work by interfering with the chemistry of the nervous system. The agents interfere with the molecules that allow signals to be sent clearly between individual nerve cells. This means that signals to vital organs (such as the heart and lungs) and to muscles become distorted. The key functions that are needed to support a healthy body then start to become ineffective. Nerve agents also affect the internal surfaces of the lungs which generate a soapy liquid, which interacting with the difficulties of breathing can lead to foaming at the mouth. Those wanting a fuller description of the nervous system processes may find the pages on acetylcholine and acetylcholinesterase to be useful.

Are there treatments for nerve agent poisoning? Yes, there have been many people exposed to nerve agents since they were first developed during the second world war and so treatments have been developed. Atropine is the most common treatment used, together with oximes such as Pralidoxime. Clear treatment protocols have been established. There can be long-term health consequences of exposure to nerve agents.

How might the nerve agent have got into the country? If the nerve agent was in the form of a contact poison (see How were the Skripals poisoned?) then it could have been applied to an object delivered to the Skripals, or perhaps given to Yulia Skripal before she left Russia and carried internationally in her luggage. As contact poisons tend not to produce much vapour, any object with such a poison applied to it and placed in a container would not be easily detected outside of the luggage. If the poison was applied some other way, for example the suggestion that a nerve agent was inserted into the air conditioning of the Skripal's car, then this would require an individual to be involved in the UK in setting up the nerve agent; that individual would possibly have brought the material into the country. The suggestion that the material came from the Porton Down laboratories is not considered to have any credibility by any of the UK analysts. However, a comprehensive investigation into the Skripal case should carry out checks that all materials at Porton Down are accounted for in order to eliminate the possibility.
     [Update 29 March 2018] See Does the detection of the toxic agent on the door of the home mean that is where the poison was deployed? for later information.

Are there dangers to other people in Salisbury? Any risk is low and gets lower with each passing day. Cross-contamination of what appears to be a contact poison (see How were the Skripals poisoned?) has been detected. Where his has been detected, the contamination has been cleared. If there was any residual contamination that has not been detected so far (and this is unlikely but not impossible), the nerve agent will slowly degrade in the environment and lose its potency. People who had been in certain locations have been advised to wash their clothing and this seems a sensible measure to reduce what is a small risk to even lower levels.
     [Update 12 July 2018] See What happened in Amesbury? and subsequent questions for later information.

Does the detection of the toxic agent on the door of the home mean that is where the poison was deployed? [Added 29 March 2018] On 28 March, the Metropolitan Police announced that: "As a result of detailed forensic and scientific examination, detectives believe the Skripals first came into contact with the nerve agent at their home address. Specialists have identified the highest concentration of the nerve agent, to-date, as being on the front door of the address."
     Note the careful phrasing "highest concentration of the nerve agent, to-date" -- this is important.
     Just as tracing an outbreak of disease requires identifying "patient zero" -- the first to be infected, the tracking of the source of a contact poison requires identifying "object zero" -- the original object the poison was contained in or coated onto. The identification of object zero is a major part of a contact poison investigation and is a significant step in attepting to identify who instigated the poisoning.
     While it is still possible that the door became contaminated as hands which had handled object zero (potentially some other item in the house) were then used on the door, this announcement raises the probability that object zero is the front door itself, which has implications for whether the poisoning had to be carried out by someone physically in the UK. As more areas in the house are tested, the clearer the search for object zero will become. As noted in How might the nerve agent have got into the country? many contact poisons give off very little vapour that may be detected so that the checking of the entire house by swabbing all possibly contaminated objects will be a slow and painstaking process. [incorrect link repaired 8 June 2018]
     [Update 12 July 2018] While the official line continues to be "Specialists have identified the highest concentration of the nerve agent as being on the front door of the address." [Metropolitan Police press release, 5 June 2018], the media are using firmer language, for example, "The Skripals were attacked in March with novichok, which police said was smeared on to their front door" [The Guardian, 5 July 2018].

What happened in Amesbury? [Added 12 July 2018] Two individuals were discovered to be ill on 29 June in Amesbury. A 44-year old female, later named as Dawn Sturgess, was taken to hospital by ambulance during the morning. In the afternoon, a 45-year old male, later named as Charlie Rowley, was taken to hospital by ambulance from the same address. Initial assessments were said to be that the illnesses could have been related to use of narcotic drugs from a potentially contaminated batch. A major incident was declared overnight 3-4 July. Late on 4 July it was announced that the two individuals had been "exposed to the nerve agent Novichok". On 8 July an official announcement stated that Dawn Sturgess had died. A few days later it was reported that Charlie Rowley had regained consciousness.

How might the two people in Amesbury have got exposed to the Novichok? [Added 12 July 2018] The predominant hypothesis in early July is that Sturgess and Rowley may have come across a container that had held a quantity of the Novichok poison. It was reported that the two individuals were exposed to a "high dose". The container for the poison may also indicate whatever method had been used to apply the poison to object zero [see Does the detection of the toxic agent on the door of the home mean that is where the poison was deployed?]. The container might therefore be similar to a syringe or a tube that contains a cosmetic product. It might also be a pot with some application device within it, such as a brush. There may also be other contaminated items, such as protective clothing worn by the person or persons who deployed the poison. As the poison was deployed in winter conditions, winter clothing in the form of coat and gloves would have offered singificant protection. Public Health England has issued official guidance which includes: "we still advise the public not to pick up any strange items such as needles, syringes or unusual containers".
     [Update 13 July 2018] A Metropolitan Police announcement on 13 July stated that on Wednesday 11 July a "small bottle" was recovered during searches of Charlie Rowley’s home in Amesbury. Tests by Dstl at Porton Down have since confirmed "that the substance contained within the bottle is Novichok". A separate UK statement the same day indicated that the government has invited "independent technical experts" from the OPCW to travel to the UK "early next week" to independently confirm the identity of the poisonous substance.

How long can this Novichok persist in the environment? [Added 12 July 2018, one sentence recast for clarity 13 July] The lack of published scientific literature on this particular compound hinders any independent assessment of the persistence in the environment of this material. Organophosphorus nerve agents, of which the Novichok family are a subset, will degrade in the environment, but rates vary between the specific compounds. There have been only a few specific official public statements on the subject of longevity in the environment of the Novichok involved in the Salisbury poisoning.
     Ian Boyd, the Chief Scientific Adviser at the Department for the Environment, Food and Rural Affairs, was reported to have answered a question about persistence of this Novichok at a public meeting on 19 April in the following terms: "It does not degrade as fast as you think it does. The chemical does not degrade quickly. You can assume that it is not much different now from the day it was distributed", adding, "This chemical can degrade in the environment but, under [some] situations, it will degrade much more slowly." [
The Guardian, 19 April 2018]
     The OPCW [see What is the Chemical Weapons Convention (CWC)?] noted in a press release dated 4 May 2018 that "analysis of samples collected by the OPCW Technical Assistance Visit team concluded that the chemical substance found was of high purity, persistent and resistant to weather conditions", although this information did not appear in the unclassified summary report published on 12 April 2018.
     If the poisonous material is within a container that is protecting it from the environment, the material is likely to have a longer potency. Neil Basu of the Metropolitan Police was reported as telling a meeting in Amesbury on 10 July: "If it was sealed in a container and it was in a landfill site it would effectively be safe because it would not be touched by anyone and it would last for probably - I've been told by scientists - 50 years" [BBC News, 11 July 2018].
     On balance, it would seem that this particular compound persists in the environment more than might have been initially expected. However, this does not mean that traces in the environment would pose any risks to the general public in practical terms. Any poison that remains in a container would pose an entirely different scale of risk, hence guidance not to handle unknown objects in the area.

Novichoks - myth or reality?

What is a Novichok? Novichoks are a group of nerve agents which act in the same way as the more traditional organophosphorus nerve agents (see What does a nerve agent do?) However, they have a different structure which may lead to some other additional toxic properties. Only some of the Novichoks have had their structures published and the information detailing these structures is from very few sources.

Is there clear evidence Novichoks exist? The first public information about Novichoks was revealed in the 1990s. While there is much unconfirmed information that has never been possible to independently assess, there is enough confirmed information to be confident that such a programme did exist, even if there is a vagueness about what the absolute scale was. Evidence for the existence of the Novichok family of compounds was examined by the OPCW Scientific Advisory Board (SAB) (for details of the OPCW see What is the Chemical Weapons Convention (CWC)?). An SAB report from 2013 included the following:

In 2008, a book authored by Vil Mirzayanov, a former Soviet scientist, reported that Soviet scientists had investigated a new class of nerve agents commonly referred to as "Novichoks" (newcomers), which were suitable for use as binary weapons. The structures shown in the book incorporated an acetamidine or guanidine group into a sarin-like structure in place of the alkoxy group. While some of these structures fall within the generic definition of Schedule 2B(4) chemicals, it was reported that some were non-scheduled analogues, wherein the alkyl group attached directly to phosphorus was replaced by an alkoxy group. The compounds were reported to have high toxicity and no recorded industrial use. There is very little information available on those compounds in open-source literature, and the existence and properties have not been verified in peer reviewed literature. The SAB is therefore not in a position to make further comments.

The SAB operates by consensus and traditionally only uses information in the public domain that is possible to subject to public scrutiny and to peer review. That the SAB could not make any further comment should not be construed that the members of the SAB had any doubts that there was a Novichok programme.

Could Novichoks be made outside of Russia? Yes, although assessments of the difficulty of making each of the known specific Novichoks vary. As the compounds are highly toxic, synthesis of these chemicals would need to be carried out in facilities with levels of protection that are operating at high standards. Additionally, the use of any nerve agent as an assassination poison requires production of the relevant material in a form that will enter the body of the target(s). This requires a further skill set. Overall, this leads to a conclusion that such a poison would need to be created and handled in laboratories of the standards that primarily exist in government facilities.

Aren't there reports that Novichoks were designed to be easily made? There were some unconfirmed reports suggesting a simple binary weapon where two easily available compounds could be combined. Contradicting this is information in a 1993 interview with one of the researchers, Vladimir Uglev, in which he is asked about the new binary system and he says, according to the FBIS translation: "Such a weapon, if it existed, would be ideal to the military in all respects -- any country, even having assumed the obligations not to produce chemical weapons, could nevertheless produce components of binary gas with an easy conscience and use them as insect-killers or dies [presumably "dyes" -- RG]; at the same time, it would be ready for chemical warfare if the necessity arose." He goes on to say "As far as I know, such perfect weapons don't exist yet." So the Soviet/Russian aim was to have such a binary weapon using easy to handle chemicals but there didn't seem to be a successful conclusion. This is borne out in other interviews/reporting. However, binary Novichoks using chemicals that are harder to handle were clearly developed.

How credible were claims that Novichoks would be undetectable? The primary lack of detectability for the Novichoks was to come from the Soviet/Russian intention of keeping them secret. The 1980s/1990s detection kits for nerve agents would have had difficulty picking them up as they had some significant differences from more traditional nerve agents. Once the first details of the Novichoks were made public, laboratories around the world started working out how to detect them.

How easy/hard would it be to tell the origin of the Novichok material used in Salisbury? Chemical samples can contain a lot of information that might give indications of the origin of the material. For example, there may be traces of by-products or of intermediate compounds used during the creation of the final product that would give clear indications of the methods used for synthesis. This might then provide some evidence, although not proof, of the origin of the material. There can also sometimes be other data, such as isotopic composition, that can provide further evidence. More significant would be any evidence of how the material got to be in contact with the Skripals, as this may give further indications of the source (see How might the nerve agent have got into the country?).
     [Update 13 April 2018] The OPCW summary report published on Thursday 12 April indicated that "the toxic chemical was of high purity. The latter is concluded from the almost complete absence of impurities."
     [Update 14 April 2018] A letter from the UK National Security Adviser to the NATO Secretary-General noted that "the DSTL analysis does not identify the country or laboratory of origin of the agent used in this attack", a statement that followed on from what the head of Dstl had said in an interview with Sky News earlier in the month.

Novichoks and international law

What is the Chemical Weapons Convention (CWC)? The Chemical Weapons Convention is an international treaty that prohibits the use of chemicals as weapons that rely on their toxic properties. The text was agreed in 1992, it was opened for signature in January 1993 and entered into force on 29 April 1997. The CWC established an international body, the Organization for the Prohibition of Chemical Weapons, based in The Hague. A research briefing on the CWC in the context of the Salisbury poisonings has been prepared by the UK House of Commons Library.

Do the Novichoks fall within the scope of the Chemical Weapons Convention (CWC)? Yes. All toxic chemicals fall within the scope of the CWC. Article I of the Convention includes the prohibitions:

(a) To develop, produce, otherwise acquire, stockpile or retain chemical weapons, or transfer, directly or indirectly, chemical weapons to anyone;
(b) To use chemical weapons;
(c) To engage in any military preparations to use chemical weapons;
(d) To assist, encourage or induce, in any way, anyone to engage in any activity prohibited to a State Party under this Convention.

Article II of the Convention includes within the definition of a chemical weapon "Toxic chemicals and their precursors, except where intended for purposes not prohibited under this Convention, as long as the types and quantities are consistent with such purposes" and defines a toxic chemical as "Any chemical which through its chemical action on life processes can cause death, temporary incapacitation or permanent harm to humans or animals. This includes all such chemicals, regardless of their origin or of their method of production, and regardless of whether they are produced in facilities, in munitions or elsewhere."
     This broad prohibition is commonly known as "the general purpose criterion", although the term does not appear in the Convention text. As all toxic chemicals fall within the scope of the CWC, the Novichok family of nerve agents would be covered by the Convention. As the general purpose criterion is broad, it can be difficult to put into day-to-day operations of government systems. To ease implementation of the Convention, three schedules of chemicals were developed with a sliding scale of controls -- schedule 1 chemicals are tightly controlled while schedule 3 chemicals are subject to fewer restrictions or monitoring requirements. The Novichoks do not appear within the schedules (see the next FAQ).

Why aren't Novichoks and their precursors on the CWC schedules? When the Schedules were put together in the early 1990s, the Russian government refused to confirmed whether the Novichok family of compounds existed. At the time there were also concerns that scientists and engineers from weapons programmes of the USSR might find gainful employment in other countries, causing further proliferation problems. For example, significant funds were put into place by Western governments to establish the International Science and Technology Centre (ISTC) in Moscow (moved to Astana some years later) and the Science and Technology Centre Ukraine (STCU) to find work for scientists and engineers that reduce proliferation concerns. In addition there were concerns that the CWC needed to be put into operation as quickly as possible to get the destruction of declared chemical weapons underway. In the circumstances at the time, the Novichoks seemed to be a less important issue and so they remained on the back burner.

Should the international organization of the Chemical Weapons Convention, the OPCW, be involved in the investigation? The UK statement to the UN Security Council on 14 March included the following: "In addition the UK has welcomed the offer of technical assistance from the Director General of the OPCW and we have invited the Technical Secretariat to independently verify our analysis."
     A UK statement on 18 March stated that an OPCW team would arrive in the UK the day after and that: "The team from The Hague will meet with officials from the Defence Science and Technology Laboratory and the police to discuss the process for collecting samples, including environmental ones. These will then be despatched to highly reputable international laboratories selected by the OPCW for testing with results expected to take a minimum of two weeks."
     [Update 13 April 2018] The OPCW summary report was published on Thursday 12 April.
     [Update 13 July 2018] A UK statement on 13 July indicated that the UK has invited "independent technical experts" from the OPCW to travel to the UK "early next week" to independently confirm the identity of the poisonous substance involved in the Amesbury incident.

What might be in the OPCW report of its investigation? There are procedures written into the Chemical Weapons Convention in Part XI of the the Verification Annex -- "Investigations in Cases of Alleged Use of Chemical Weapons", although it is not clear at this stage whether a formal Article IX or X request has been submitted by the UK. Paragraph 25 of this part of the Verification Annex reads:

The final report shall summarize the factual findings of the inspection, particularly with regard to the alleged use cited in the request. In addition, a report of an investigation of an alleged use shall include a description of the investigation process, tracing its various stages, with special reference to:
(a) The locations and time of sampling and on-site analyses; and
(b) Supporting evidence, such as the records of interviews, the results of medical examinations and scientific analyses, and the documents examined by the inspection team.

The OPCW may also report whether it detects anything that might provide addiional evidence of where the toxic materials used came from (see How easy/hard would it be to tell the origin of the Novichok material used in Salisbury?). Paragraph 26 of this part of the Verification Annex states:

If the inspection team collects through, inter alia, identification of any impurities or other substances during laboratory analysis of samples taken, any information in the course of its investigation that might serve to identify the origin of any chemical weapons used, that information shall be included in the report.

[Update 13 April 2018] The OPCW summary report was published on Thursday 12 April.

Has the Chemical Weapons Convention failed to keep control of chemical weapons? All international treaties are artifacts of the time they were negotiated and of the concerns that the negotiators had in the context of the global circumstances existing at that particular moment. The Chemical Weapons Convention was negotiated at a time when the focus was on chemical weapons being used in a large scale on the battlefield. The text of the Convention was agreed only a few years after the end of the Iran-Iraq War in which chemical weapons had been used extensively. In controlling large-scale use of chemical weapons on the battlefield it has been extremely successful and over 96 per cent of chemical weapons declared under the Convention have been destroyed. The continued use of chemical weapons within the war in Syria is an ongoing challenge to the international arrangements to prohibit chemical weapons. The verification and monitoring arrangements within the CWC were never designed to pick up small amounts of chemical weapons being produced for assassination purposes but, because the CWC explicitly prohibits production of toxic chemicals for purposes that are not peaceful, its processes and procedures are being used in the context of the Salisbury poisoning incident.

Why was another agent, BZ, identified in some samples? On 14 April, Russian Foreign Minister Lavrov was reported in press reports in TASS and RT as suggesting that the OPCW designated laboratory in Switzerland (the Spiez Laboratory) identified BZ (a chemical weapons agent that is not in the Novichok family) in samples provided by the OPCW.
     When a sample, such as one from Salisbury, is sent to an OPCW designated lab, it isn't sent on its own. There are "negative control samples" (made of a material similar to that in the authentic sample that has no detectable chemical weapons agent in it) and "positive control samples" (made of a material similar to that in the authentic sample that has been spiked to contain a chemical weapons agent or other relevant chemical in it). For an active investigation of alleged use the samples are numbered and not otherwise identified so that each laboratory cannot tell them apart. In simple terms, the negative control samples protect against incorrect results from contaminated lab equipment; the positive control samples raise confidence in the lab work to identify a specific agent.
     The spike has to be of a high quality and purity, and to a known standard. As there are no standards written for the Novichoks, another material would have to be used for the spike. A good candidate for this would be BZ. [Editorial note: when I suggested to someone familiar with the classified report that the spike might be BZ in this case I was not told I was wrong -- RG].
     Thus, in an ideal world, each laboratory would report nothing detected in the negative control samples, report the spike chemical in the positive control samples and report the Novichok in the actual samples from Salisbury -- an overall detection of BZ and of the Novichok. Therefore, such a report from the laboratory does not constitute any suggestion that the Skripals were exposed to BZ.
     [Update 13 July 2018] It later became known that the control sample contained a BZ precursor, not BZ itself. The OPCW Director General told the Executive Council, in his opening remarks to its meeting on 18 April: "The precursor of BZ that is referred to in the public statements, commonly known as 3Q, was contained in the control sample prepared by the OPCW Lab in accordance with the existing quality control procedures. Otherwise it has nothing to do with the samples collected by the OPCW Team in Salisbury. This chemical was reported back to the OPCW by the two designated labs and the findings are duly reflected in the report."