There was nothing "unprofessional" about an actor smoking between takes in 1967, nor ducking his cig out of frame when they rolled. There may have even been an ashtray on the table right in front of him, as long as it was out of shot. Nobody cared back then.
I've seen smoking surgeons.
Back in the 1970s, I did a college internship in physiological psychology, wherein I worked at a veterans' hospital doing basic research on lab animals. We'd electrolytically lesion parts of the brains of rabbits and rats, and later put them through classical conditioning to determine how it affected their learning.
(Animals lovers, save the artillery: I assure you that I'm ashamed of much of it. Still, that's basic research for you -- you have to break things to see how they work, brains included. The polygraph findings from those sessions just may have helped validate treatment for some sick human kid down through the years.)
Now, those lab critters were remarkably resistant to the usual infections to which human flesh is heir. For that reason, nobody practiced sterile techniques. I know that I didn't scrub up and wear gloves and a mask. And, some of my fellow grad students would perform the brain surgery whilst puffing on a Marlboro. (
Lots of people smoked
everywhere in those days, even in a hospital wing.) We rarely lost a subject to infection and never to lung cancer.
(Years later, while still a struggling grad assistant earning $300 a month from the University, I had a chance at a $10K/annual lab job. It would have involved doing similar respiratory testing on
live dogs. I really needed the job, but was still relieved when I didn't get it.)