He said the novichok used in Salisbury was in liquid form, and that O.P.C.W. experts had collected samples from the door handle of the Skripal home, the park where the two collapsed and “a few other places where the Skripals were present.”
“One thing, perhaps, which is important to note is that the nerve agent seems to be very persistent,” he said. “It’s not affected by weather conditions. That explains, actually, that they were able to identify it after a considerable time lapse. We understand it was also of high purity.”
He said the agent could be applied with an aerosol spray or, “if you take the necessary measures, you could use it as a liquid.”
Health officials have begun a meticulous decontamination process, warning citizens of Salisbury that there might still be toxic “hot spots” in some areas, and that a thorough cleanup may take months.
Though citizens have been reassured that there is little threat to their health, the decontamination promises to be a vast undertaking, requiring backup from 190 army and air force specialists as well as input from the Defense Science and Technology Laboratory, the Home Office and the Ministry of Defense, the authorities said.
“The chemical does not degrade quickly,” Ian Boyd, the chief scientific adviser at the Department for Environment, Food and Rural Affairs, told a town meeting. “You can assume it is not much different now from the day it was distributed.”
The novichok strain, developed in the Soviet Union with the goal of evading NATO chemical weapons detection, was not included in the list of banned chemicals compiled in 1987, so Russia was under no obligation to regularly report on its stockpiles or their destruction.