PROFESSOR NICK PRIEST
Radiation Scientist
If he was contaminated in this way then when he drank it all around his lips and mouth would have been contaminated with radioactivity. There would also be a lot of it left in the cup. So he might have wiped his mouth with his hand like this, which people do. Then this becomes heavily contaminated. He could then put the hand back onto the table, so that you start a contamination trail.

SWEENEY: And the contamination trail at the Pine Bar is astounding. The cup that contained the tea, contaminated. The seven bar staff at the hotel who took the cup away, washed it, wiped it, set it out for other guests, contaminated. The Pine Bar itself, contaminated and still closed two and a half months on. The contamination itself isn't lethal, but long term risks are not known. Lugovoi and Kovtun go to the match. Seats at the Arsenal, contaminated.

Arsenal Stadium - North London

Everything points to not one, but multiple attempts to kill Litvinenko. No-one's been arrested, but the Polonium trail has made Lugovoi and Kovtun prime suspects. After Litvinenko fell sick they flew to Moscow. After Litvinenko died so did Scotland Yard. Safe and sound in Moscow Lugovoi and Kovtun protested their innocence.