Former spy Alexander Litvinenko was probably poisoned by radioactive polonium 210, health officials have said, adding they were studying the risk to dozens of people who came into contact with him.
In theory the risk was low, but doctors and nurses at two hospitals which treated him, and staff and diners at a sushi restaurant he visited before he fell ill, were being contacted.
Professor Roger Cox of the Health Protection Agency said Friday a “large quantity” of alpha radiation “probably from a substance called polonium 210″ had been detected in Litvinenko’s urine.
“We know he had a major dose,” added HPA chief executive Professor Pat Troop, adding that it was unprecedented that “someone has apparently been deliberately poisoned by a type of radiation” in Britain.
Litvinenko, who died in a central London hospital late Thursday, would have had to have eaten, inhaled or taken it through a wound, she added, but said it was a police matter about how that was done and how the substance was obtained.
Staff at the HPA had worked through the night to assess the risks for people who came into contact with him since he first fell ill on November 1, and they were working closely with the two hospitals involved in his treatment.
Physical contact with Litvinenko himself would not pose any risks, but the dangers increased when there was contact with excretia from the body such as urine, faeces and to a lesser extent sweat, Cox said.
But he added: “The risk to those individuals from taking in contaminated blood, urine or faeces from Mr Litvinenko is very small and the risk we believe is insignificant.”
All staff were being monitored as were the hospitals, the University College Hospital London and the Barnet and Chase Farm Hospital in north London.
Troop declined to speculate how many people might have been in touch with the dead agent. “We’re talking minimum of 10s because he was in hospital for several weeks. During that time a number of staff looked after him,” she said.
Asked about what caused Litvinenko’s death, she added that was for the coroner to determine and their job was to assess the risk to others, including the wider public.
Cox said that he could not rule out that the polonium came from natural causes, but added that this was “unlikely.”