Before the interrogation scene with Blofeld a huge deal is made out of the woman applying the Heracles robot poison to her wrist, and James Bond then grabbing her wrist. I'm assuming to make us think "oh no, he's got the poison on him". However, far earlier in the movie, James Bond is already sprayed with poison lethal to every single Spectre member.
The movie explicitly shows that Blofeld was one of the targets of the poison from earlier on (scene at Q's house), and very explicitly tells us that the poison "never ever" disappears once in your body.
My memory might betray me, but could James Bond not already have known that he was contaminated and lethal to Blofeld?