Producer Rob Swire, of Pendulum and Knife Party, was left frightened and confused when he experienced complete hearing loss in his left ear for four days. 

Finally he figured out the problem: a key component in most e-cigarettes called propylene glycol. The chemical is used as a solvent in e-juices and is ototoxic, meaning toxic to the cochlea or auditory nerve.

Apparently due to the relatively new emergence of e-cigs, there isn’t too much information available. After some extensive research Swire came up with some links to keep his followers informed: check them out here, here, here and here.

Swire feels so passionately about the matter that he promised to fund research towards the cause.

Be careful vaping, kids!

[Source]