Jean King, director of tobacco control at Cancer Research UK, said the research was further proof of the need to tackle smoking, particularly among the young.
He has pointed to the fact that he has family members in the UK and a British bank account and is in receipt of a state pension as proof of his close links to the country.
So far, the UK government has stood by its original claim, though it has offered little in the way of proof -- other then to say the weapons will eventually be found.
Parliament's Joint Committee on Human Rights said in its June 2011 report on extradition that the burden of proof for extradition should be increased - but the US argues that it cannot ask the UK to hand over a suspect unless its request has already met the same test in its own courts.
He has been in the UK since last year but was told earlier this month his asylum application had been rejected because he had given insufficient proof of his identity and work.