PG can affect the ears:
A list of symptoms when quitting tobacco and changing to an ecigarette
It has made mine more noticeable to me when things are quiet. Not enough to drive me completely batty....
A list of symptoms when quitting tobacco and changing to an ecigarette
PG and tinnitus
A very small number of people with pre-existing tinnitus report that vaping of PG-based refills negatively affects their condition: the tinnitus worsens. It is extremely hard to put any kind of hard number on such an effect but it must be in the region of 1 in 10,000 persons or less. This effect is believed to be due to an ototoxic effect of PG for some people and the likelihood that vapour will permeate the ENT region including the inner ear. The solution would be to change to an all-glycerine refill, which at 2015 are becoming easier to find.
It has made mine more noticeable to me when things are quiet. Not enough to drive me completely batty....