Heja,
I can’t say I’ve ever heard of that however, I know that air quality and elevation can be a factor related to non-genetic hair loss. That said, it could be a coincidence and you could just be experiencing normal genetic hair loss. It would help if you provide the community with more information such as your age, family history of hair loss, etc. also, a picture is worth 1000 words. I suggest posting some pictures of the area of concern so that we can take a look at the pattern and level of loss. But at the end of the day, only a qualified physician can’t tell you for sure what’s going on. most of the time, a general practitioner won’t be able to tell you, so you would have to go to a hair restoration specialist or a trichologist/dermatologist.
Best wishes,
Bill