Years ago, I spoke about this same subject with my doctor, initially I told him that I smoked from a pipe instead of a bong because I theorized about water vapor collecting in my lungs,,,, his reply was that bongs are much better for our health than pipes. He then continued by claiming that people in the tropics where the humidity is extremely high (he used Northern Queensland as an example) do not develop lung problems because of water vapor on the lungs.... later in that year I approached another GP with the same inquiry, and she gave a similar explanation.
Now I'm not saying that this is carved in stone, but it does make sense to me.
Now I'm not saying that this is carved in stone, but it does make sense to me.