Glossary
An evidence-based analysis of propylene glycol (PG) safety in cosmetic products, addressing the common internet myth that links it to antifreeze. Propylene glycol is FDA-approved as a food additive, classified as GRAS (Generally Recognized as Safe), and has been used safely in cosmetics, food, and pharmaceuticals for decades.
The persistent internet claim that propylene glycol is antifreeze is technically misleading. Toxic antifreeze uses ethylene glycol, a different chemical. Propylene glycol is used in non-toxic antifreeze specifically because it is safe. The FDA approves propylene glycol as a food additive, and it is found in ice cream, salad dressing, baked goods, and medications.
This is similar to saying water is a chemical solvent found in sewage, which is technically true but deliberately misleading. Context matters: propylene glycol at cosmetic concentrations (typically 1-5 percent) has an extensive safety record spanning decades.
While PG is not toxic at cosmetic concentrations, it can cause contact irritation in some individuals, particularly at high concentrations or on damaged skin. People with eczema or severely compromised skin barriers may experience stinging or redness from products containing significant PG concentrations.
For consumers who prefer to avoid propylene glycol regardless of safety data, products labeled PG-free or those using glycerin as an alternative humectant are widely available. Natural, anhydrous formulations avoid the question entirely by not containing water-phase ingredients.
At cosmetic and food concentrations, propylene glycol is not toxic. It is FDA-approved as a food additive (GRAS), used in medications, and has decades of safe cosmetic use. Toxicity requires ingestion of very large quantities, far exceeding any cosmetic exposure.
For most people, there is no evidence-based reason to avoid PG in cosmetics. If you have sensitive or compromised skin and experience irritation from PG-containing products, switching to PG-free alternatives is reasonable. The choice is often personal preference rather than safety-driven.
PG is a humectant (attracts moisture), solvent (helps dissolve other ingredients), and penetration enhancer (helps other ingredients absorb better). It provides lightweight moisture and improves product texture and ingredient delivery.
Keep Learning
Browse hundreds of terms covering honey, beekeeping, and natural skincare.