Also known as: 1,2-Propanediol, PG
Propylene glycol is a synthetic diol used as a solvent, humectant, and penetration enhancer. It is effective at dissolving many cosmetic ingredients and improving their skin penetration. At higher concentrations it can cause irritation in sensitive individuals. Widely used in pharmaceutical and cosmetic formulations. Generally well-tolerated at typical cosmetic use levels.
Comedogenicity ratings are based on the rabbit ear assay model. Individual skin responses vary. See our article on comedogenicity ratings for context.
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