What is Oleth-10?
Oleth-10 is an emulsifier that helps oil and water mix. A higher-ethoxylate oleth that is milder than oleth-3, rated 2/5.
You may see it on labels as Oleth-10, Oleth 10, so it can hide under more than one name in an ingredient list.
Where Oleth-10 shows up
You'll most often find Oleth-10 in almost any lotion or cream, where it keeps the oil and water phases blended. Separately from clogging, its irritancy is rated 1/5 — low, so it's unlikely to sting or sensitise on its own.
Is Oleth-10 bad for acne-prone skin?
That low score makes Oleth-10 a reasonable choice even for acne-prone skin. As always, individual reactions vary, but it is not a likely cause of clogged pores.
Note for fungal-acne (malassezia) sufferers: Oleth-10 is commonly avoided in fungal-acne routines, since it falls into the fatty-acid or ester families the yeast can feed on. The evidence there is looser than for comedogenicity — see our fungal-acne checker for context.