Because the members of the SS were considered extremely valuable to the Nazis, they had their blood type tattooed on their arm.
Nigel says that "In 1978, the KGB assassinated a journalist in London with a poison-tipped umbrella." He's referring to the case of Georgi Markov, a Bulgarian dissident believed to have been killed by the Bulgarian secret service with assistance from the Soviet KGB. The umbrella wasn't actually poison-tipped; it was a disguised special-purpose gun used to fire a tiny pellet containing poison into Markov's thigh. Markov died four days later.