# Thioglycolic acid esters

URL: https://app.greenveil.ai/ingredients/ingredient_source_ref_substance_id_28835
Categories: beauty
Identifier: annex_ref:III:2b

> Thioglycolic acid esters. Greenveil chemical-concern score: 70/100 — High concern based on regulatory listings.. Compiled from 2 published data sources.

## Safety assessment

- Chemical concern score: 70/100 — High concern based on regulatory listings.
- Confidence in this assessment: High
- Is it a concern? High concern: no hazard classifications on record. It is restricted in EU cosmetics.
- Rationale: Thioglycolic acid esters is restricted in cosmetic products under Annex III of the EU Cosmetics Regulation (EC) 1223/2009.

## Regulatory status

- EU: Active — Cosmetics Regulation annex III / ref 2b.
- EU: restricted — Annex III of EU Cosmetics Regulation (EC) 1223/2009: substances which cosmetic products must not contain except subject to the restrictions laid down. Product types: Hair waving or straightening products Maximum concentration: (a) 8% (b) 11% The abovementioned percentages are calculated as thioglycollic acid Other conditions: (a) General use ready for use pH 6 to 9.5 (b) Professional use ready for use pH 6 to 9.5 Conditions of use and warnings: Conditions of use: (a) (b) May cause sensitization in the event of skin contact Avoid contact with eyes In the event of contact with eyes, rinse immediately with plenty of water and seek medical advice Wear suitable gloves Warnings: Contains thioglycolate Follow the instructions Keep out of reach of children (b) For professional use only

## Expert safety opinions

- SCCS (EU Scientific Committee on Consumer Safety): no opinion on file.
- CIR (Cosmetic Ingredient Review (US expert panel)): no opinion on file.

## Data sources

- CosIng (updated 2026-09-23): https://ec.europa.eu/growth/tools-databases/cosing/details/28835
- EU CosIng Cosmetics Regulation Annexes (updated 2010-10-17): https://ec.europa.eu/growth/tools-databases/cosing/reference/annexes/list/III

_Assessed by Greenveil._