I just have to add a clarification, as I am a chemist: Even though they have similar sounding names, PEG or Poly(ethylene glycol) also known as poly(ethylene oxide) (PEO) or polyoxyethylene (POE) is not the same as PG (Propylene glycol, known also by the systematic name propane-1,2-diol, is an organic compound (a diol alcohol). PEG is a polymer and its properties vary on chain length, so you have to make sure you are addressing the right form (chain length) when looking at its potential toxicity. For a very general overview of the differences just look at wikipedia:__http://en.wikipedia.org/wiki/Polyethylene_glycol_... reading!