What it is
Octadecene is an eighteen-carbon olefin, most commonly the alpha-olefin 1-octadecene. In cosmetic formulas it acts as a lightweight emollient and helps improve spreadability and skin feel. It is also used as a building block for other ingredients and can serve as a carrier or binding agent in sun care products.
Safety & warnings
Octadecene is generally regarded as a low-irritation emollient hydrocarbon and is not a known fragrance allergen. As an oily hydrocarbon it may feel heavy on very oily or acne-prone skin, though it is not strongly associated with comedogenicity.
Origin & sourcing
Synthetic. It is a hydrocarbon typically produced from petrochemical feedstocks, though long-chain olefins can also be sourced from other carbon chemistries.
Questions everyone asks
What is octadecene used for in skincare?
It is a long-chain hydrocarbon that works as a lightweight emollient, improving how a product spreads and feels on the skin.
Does octadecene have any active sunscreen effect?
No. It is a texture and emollient ingredient, not a UV filter, so it does not contribute sun protection.