let's get more reaction now from doctor richard guthrie.dependent expert on biological weapons. think you forjoining us. what you make of what you heard? it seems there have been further contamination with novichok around the area of salisbury. what you make of what you have heard? what we've from daniel is correct. there may be, he referred to equipment, there may be for example gloves or a jacket the person who is using the poison in the skripal case may have tried to put away somewhere that might not be easily found and it may not have been spotted as people were looking for things to clean up. how alarmed at think people will be or should be in this area? given this is several miles from salisbury, they were reassured at the time of course that the clean—up had taken place. we have seen people on—site from the army and in special sues for weeks after that attack. how concerned should people be now that it has not been contained? some of this material was obviously somewhere unexpected. i think the chances of a lot of people being expose

medical director at salisbury district hospital dr christine blanshard says: dr richard guthrie is art and joins us via webcam from bath. doctor guthrie, thank you for joining us so late at night, in particular. tell us a little bit more, just remind us about how novichok works, and how it is delivered, if you like. well, novichok is one of the groups of nerve agents, so they interact with the body by affecting the signals between nerve cells. and of course, the nervous system is required to support those basic functions of life such as your breathing and your heartbeat. as soon as those systems are interrupted, of course, somebody can be extremely ill, and of course, with a big enough dose, can lead to death. what do you know about the sort of lifespan of a batch of novichok? because we have been told that it does degrade, it does deteriorate if it is exposed to rain and sun. yes, well, there is a variety of novichoks, but the a234, as it is known, which is the agent used against the skripals, it does degrade in the environment but it degrade in the environment but it degrade is low

joining me now from bristol is chemical weapons specialist, dr richard guthrie.th novichok? the most likely method is an item discarded by the perpetrator of the attack on the skripals. it looks very likely that the attack on the skripals was carried out by pasting the poison on their door handle. that individual, of course, will have wanted to make sure they we re will have wanted to make sure they were protected, so probably wearing a thick coat, gloves, they would not wa nt to a thick coat, gloves, they would not want to wear what was obviously protective equipment, they may have had a small amount of the material left over. you would expect a halfway competent would—be assassin to dispose of those relatively carefully, because they would be a forensic gold mine. but it is quite possible, and i think the implication is, it is one of the leading lines of inquiry, that one of these items has not been hidden as well as expected and has been found, and that two individuals have become contaminated because of it. does that mean the decontamination process after the

dr richard guthrie, an independent chemical weapons expert, joins us now from our bristol studio.likely do you think that this nerve agent is the same that this nerve agent is the same that was used on the skripals. that this nerve agent is the same that was used on the skripalslj think it is highly likely. as an investigator, the first line line of enquiry i would have would be could this have been jettisoned, enquiry i would have would be could this have beenjettisoned, disposed of, idea perpetrator of the skripals. if you put nerve agent on the door handle, which appears to be the door handle, which appears to be the way the skripals were poisoned, you would have a way to protect herself, gloves, a coat, perhaps a container the material had been in in the first place. now, the most competent would—be assassins would wa nt to competent would—be assassins would want to dispose of that carefully because it would have a lot of forensic evidence on it. it is possible it got disposed of in a haphazard way. perhaps the two adults that were exposed to it on the weekend were some such p