Propylene Glycol

Propylene Glycol is from petroleum. Is it safe for cosmetics?
Anyone has experience to use it?

Thanks in advance any sharing.


  • Propylene Glycol has GRAS status. You won’t get safer than that.
  • @ngarayeva001, thank you!
  • @ngarayeva001, what you think about the comparison between propylene glycol and glycerin?
  • In what sense? They both are safe.
  • I believe they are edible, if they are food grade. Not sure what you are comparing? 
  • Humectant, helping active ingredients to absorb into skin, etc.
  • I'd say it depends on the type of ingredient you are intending to aid the penetration. You might be able to find a test online. For example, for Ethyl Ascorbic Acid, Glycerin is only second to Propylene Glycol. It depends if you want to have the additional benefits of glycols or diols in your formulation as well. 

  • @jemolian, thank you so much. 
    You mean it is depending on molecular weight of ingredients that I need to use propylene glycol to help ingredients penetrating into skin;
    molecular weight of ethyl ascorbic acid is about 204 g per mol so it needs propylene glycol?
  • i found propanediol having same formula with propylene glycol but structure is different 

  • Which is better:  butylene glycol or propylene?  I see formulations call for propylene and seldom butylene and despite my research can’t understand why
  • I prefer Butylene Glycol as a humectant but Propylene as a solvent. It's a more effective solvent than the others (for example when solubilizing Ferulic Acid.)
  • For penetration enhancement, Dimethyl Isosorbide outperforms PG imo. 
  • @emma1985 thanks a lot for your sharing. I google and found that butylene is banned many countries due to its toxic and propylene glycol is very safe.
  • This is the first time I’ve heard that butylene glycol is toxic and banned. Do you have links/references?
  • PharmaPharma Member, Pharmacist
    Which butanediol are we referring to here? 1,3-butanediol, although by proper definition not a glycol, is the most often used isomer but by far not the only one. Apart from that, butanediols also come as stereoisomers which complicates things even further.
    1,4-butanediol certainly is problematic because it's quickly metabolised to GHB. Therefore, it is a prodrug or at least a precursor and therefore regulated.
  • @Pharma Thanks a lot!

Sign In or Register to comment.