So, a diol alcohol isn't an alcohol? Isn't that kind of like saying a latex paint isn't technically a paint?
As to toxicity... again, the FDA classifies it "Generally Regarded As Safe" so, yeah, pretty much "not poisonous" as long as you don't overdo it... like regular spirits. As someone else mentioned, *everything* is poisonous if the dose is large enough.
My most intimate knowledge of propylene glycol is as the carrier for almost all coffee flavorings. That French Vanilla or Hazlenut Supreme flavored coffee you get from the coffee shop almost certainly contains propylene glycol.