I worked for a globally-distributed company. The founder, org, and some engineers were located in Indonesia. We had a company-wide "working retreat" in Bali for a month where I got to work alongside our Indonesian Software Engineer team.
At some point, I got up and started to refill a disposable Dasani water bottle I had been using at the water dispenser. The senior dev comes over to me looking shocked.
"What are you doing?" "Umm...I'm getting some more water?" "Don't you know about BPAs?" "Yeah"
He began to explain I shouldn't re-use water bottles because it gets more BPAs in the water. I just said "thanks, I'm okay" and kept re-using the bottle. I also asked around, it was a common belief among the rest of the group.