GLYCERYL THIOGLYCOLATE is graded C (Moderate) by Expert·ING, based on COSING regulatory data. It is restricted under EU COSING — AnnexIII-SAFETY-.
GLYCERYL THIOGLYCOLATE
Safety grade: C
This is a chemical compound used in hair relaxers and straightening treatments that works by breaking down the protein bonds that give hair its natural curl or wave pattern. It allows the hair structure to be reformed into a straighter shape.
It acts as a reducing agent in hair waving and straightening products, breaking disulfide bonds in the hair's protein structure to alter curl and wave patterns.
Graded using: COSING.
- EU COSING — Restricted
Last verified: May 26, 2026
Safer alternatives to GLYCERYL THIOGLYCOLATE
- AMMONIUM THIOLACTATE — Grade A. Reducing agent that breaks disulfide bonds like glyceryl thioglycolate.
- CYSTEINE — Grade A. Reduces disulfide bonds in hair protein to enable wave/straighten effects.
- CYSTEINE HCL — Grade A. Cysteine salt that acts as reducing agent for hair structure alteration.
- THIOLACTIC ACID — Grade A. Reducing agent that breaks disulfide bonds for hair waving or straightening.
Other Hair Waving Or Straightening ingredients
- SODIUM SULFITE — Grade C
- THREONINE — Grade A
- THIOGLYCERIN — Grade A
- POTASSIUM THIOGLYCOLATE — Grade C**
- BIS-AMINOPROPYL DIGLYCOL DIMALEATE — Grade A
- ANGELICA GIGAS ROOT EXTRACT — Grade A
- GLYOXYLIC ACID — Grade A