The ingredient, explained
Thiolactic Acid
2-Mercaptopropionic acid
Ingredient guide
What it is and what it does
About this ingredient: EU CosIng ingredient registry (via Open Beauty Facts taxonomy) ↗
- Antioxidant
- Limits oxidation, including deterioration of formulation ingredients. This label alone does not show a clinical antioxidant effect in skin.
- Depilatory
- A technical role associated with removing unwanted body hair.
- Hair waving or straightening
- Changes hair structure to allow waving or straightening.
- Masking
- Reduces or conceals the formula's underlying odour or taste.
- Reducing
- Chemically changes another material through reduction.
Function definitions: European Commission ingredient function definitions (SCCNFP/0299/00, pages 16 to 20) ↗
Registry functions describe possible formulation roles, not results for a finished product. A dictionary entry is not an approval or a safety assessment.
A closer look
What the research shows
We have not yet published a checked study for this exact ingredient. This is a gap in our coverage, not a finding that research does not exist or that the ingredient is ineffective.
Ingredient research is not proof that a product containing this ingredient works.
Follow the formula
Products containing this ingredient
From the wider catalogue. Linked by the ingredient list, without an efficacy ranking.
Names and identifiers
- INCI name on ingredient lists
- THIOLACTIC ACID
- CAS registry number
- 79-42-5
- EC number
- 201-206-5
Sources for this ingredient record
- EU CosIng ingredient registry (via Open Beauty Facts taxonomy) ↗ · ODbL 1.0 (Open Beauty Facts database) · Recorded Aug 8, 2026



