I have been telling people that I actually experience this but no one believes me. Can someone please shed some light on this. I work in a blood lab and when I open alot of Tiger top serum tubes to pour/aliquot off, though I'm wearing my face shield, I'm getting a blood-like taste in my mouth that I believe is coming from all of the serum that I'm pouring off. I swear I can taste the blood only subtle though. What chemistry could be causing this phenomenon?