[jaebaeli]

I need to know if the vapor created by heating propylene glycol (as in fog machines or any other vapor mechanism) is toxic or not.

Does propylene glycol become something different when it's converted to vapor?

For instance, if it could possibly be toxic in liquid form, is that still true in vapor form?

I'm not a chemistry person, so not sure if I'm asking with the proper terminology. I am an author, and this is research for one of my books, I would like to hear from chemists on this issue.

Thanks so much for any information.
Best,
Jae Baeli

[Rachel]

I believe the FDA regards propylene glycol as being rather safe. In fact, it's found in many of our common daily products, like creams and shampoos, that have a scent. I believe it's used because it gives a sweet scent, and because it's low toxicity.

[Arkcon]

I would assume its safe, in vapor form.  A good way to check would be to read the label for hazards.  You may also want to google for "propylene glycol MSDS", that would give you the possible hazards if, for example, a warehouse full of it caught fire, or something like that.