select search filters
roundups & rapid reactions
factsheets & briefing notes
before the headlines
Fiona fox's blog

expert reaction to reports of two people being critically ill after being exposed to an unknown substance in Salisbury

Two people have been found critically ill after being exposed to an unknown substance in Salisbury.


Prof Malcolm Sperrin, medical physics expert, said:

“We need to keep view of reality.  The symptoms may be related to some sort of exposure to common domestic chemicals – I am not saying that is the cause but we could be looking at a coincidence.  Forensic evidence will be collected and managed for the common good and will comprise environmental material, body material and clothes including monitoring carried by the emergency services.  I expect updates to be issued since there is a clear need to know at local, national and international level.  Don’t assume Russian involvement!”


Prof Alastair Hay, Professor (Emeritus) of Environmental Toxicology, University of Leeds, said:

Do we know what conditions to two people affected will likely be being kept in hospital?

“I’m not sure about this – we can’t know for sure.  I suspect individuals might well be in rooms away from others.  There would sensibly have been some care taken in removing clothing in case this was contaminated.  I’m not sure whether they will be in quarantine as the evidence is unclear – as microbiological agents and radioactive poisoning seem to perhaps be less likely, quarantine may be unnecessary, but they may do so as a precautionary measure until more is known.  The usual precautionary measures would be in place when collecting body fluids as these measures offer a degree of protection.”


Anonymous comment from an ex radiation biologist:

“Hospital policies are not to release any specific detail on patients’ conditions or treatments unless with consent and then not if it is prejudicial to any ongoing inquiries.  Hence I think that we are not likely to get further details at present.

“However all hospitals have to plan and exercise procedures for the possibility of such eventualities – e.g. receiving patients either contaminated and/or poisoned.  These would have been implemented.  What those conditions are will depend on the patients’ clinical states and on the possible causes for their symptoms.

“Simply put, there are procedures in place but we won’t know any specific details until we are told!”


Prof Malcolm Sperrin, medical physics expert, said:

“The speed at which this has occurred suggests this is probably not radiation – radiation poisoning tends to take tens of hours to several days to show symptoms after exposure.  Some of the symptoms being described in these two people suggest this may have been chemical, but we can’t be sure.  The time delay after exposure to chemical tends to be seconds to minutes.  Using an encapsulated chemical delivered directly could have given a person responsible time to escape.”


Anonymous comment from an ex radiation biologist:

“From the media, all we know is that the Russian and his daughter are seriously ill in hospital, having been found collapsed in a shopping centre in Salisbury.  We know nothing more about their symptoms apart from one witness stating that “he appeared out of it”.  We also know that the nearby restaurant and pub have been secured and that the streets nearby have been decontaminated with hoses.  His house is also secured.

“Not much to go on!  A question has been asked by journalists about radioactive substances.  Unless the initial dose is really massive then there is a delay before any symptoms show.  To cause unconsciousness over a short space of time would require an implausible absorbed dose from either ingested or inhaled radioactivity.  Also even if there had been a delay from initial ingestion, it would be most unlikely that there would be synchrony between symptoms with father and daughter.  Frankly I would put radioactive substances to one side.

“If the outcome is not just something like a couple of dodgy kebabs – again less probable with both individuals being symptomatic at the same time and with considerable rapidity if they had just eaten there – then I would look for a chemical source.  Decontamination at the scene would also suggest that possibility.  However we shouldn’t totally ignore biological contamination of food or the environment.  However the latter would have caused a wider response from PHE and the authorities.

“We have no information on symptoms apart from severity so I wouldn’t like to speculate on possible chemicals which can range widely and include the increasing range of designer drugs so that this includes not only those designed for chemical warfare but also those for the new range of artificial highs.  We could be looking at self-inflicted accidental overdoses or a targeted attack.

“Toxicologists would have received samples from the patients of both fluids and tissues as well as being given the symptoms for the patients being treated and their response to particular drug therapies.  From the samples they can investigate possible chemicals and their metabolites produced in the tissues.  This can take a variable amount of time dependent on the knowledge about each chemical.

“I certainly would imagine that all the relevant agencies would be working together to pool expertise and knowledge – certainly from my experience this has indeed been the case.  From the health point of view PHE would be working not only with their own laboratories but also with the relevant expertise in universities and other such institutions such as Porton Down.”


Prof Alastair Hay, Professor (Emeritus) of Environmental Toxicology, University of Leeds, said:

“The first clue is signs and symptoms in the individual. A second may be the circumstances in which someone is found.  Ideally it would help to question someone about this but if they have collapsed you have to test for substances.  Signs and symptoms will give a clue about candidate agents.

“Standard blood tests will be done to assess electrolyte levels and liver and kidney function. Individuals will be receiving intravenous fluids anyway and it is essential to maintain fluid balance.

“Intensive care facilities in hospitals are best placed to look after poisoned patients as they have the necessary skills and equipment.

“As for tests, a variety of fluids will be investigated. Blood, saliva and urine will all be tested. Urine may provide clues for substances excreted more rapidly.

“Given the apparent rapidity of onset of symptoms a bacterial or viral cause seems less likely but we know nothing at this stage about how the couple were feeling hours earlier. So a microbiology lab may well do a range of screening tests to check for a bacterial cause. But this will depend on what the clinical team feels is appropriate.

“Signs and symptoms give a clue about possible candidate chemicals or drugs and the hospital’s own laboratory may be able to do some of the testing.

“Other labs at Guy’s hospital or in Birmingham are also equipped to screen for a wide range of substances. And finally, there is the government’s Chemical Defence laboratory at Porton Down which has state-of-the -art equipment to look for trace amounts of substances.

“Individuals cannot provide unlimited amounts of blood for testing so investigations will be guided by the clinical team.  Some tests are rapid and some candidates will be looked at quickly But if the cause is more unusual body fluids will require significant clean-up preparation before they can be put in an instrument. So this could take a day or several days.

There will be active co-ordination with a whole range of agencies and hospital departments in a case like this.”


Comment issued on Monday 5 March:

Prof Alastair Hay, Professor (Emeritus) of Environmental Toxicology, University of Leeds, said:

“It is impossible to speculate at this stage about the substance.  If PHE say there is no wider risk this may suggest some very specific contact with the substance and limited spread.  It would be helpful to know what they used to hose down the area.  In the end it will be signs and symptoms and specific blood, saliva or sputum, urine, and possible faecal testing that will tell us what it was.  It was classed as a major incident.  Part of the investigation now will be working out if it is known for certain where contact with any offending agent occurred.  Was it declared a major incident because of who was affected or because of the rate of onset of symptoms?”


Declared interests

Prof Alastair Hay: “No conflicts of interest.  I worked on UK government committees (from 1989 until 2015) and an EU committee (2005-14) that recommended standards for chemical exposure in the workplace.  Over the years I have investigated some 6 allegations of use of chemical weapons.”

None others received.

in this section

filter RoundUps by year

search by tag