Based on the available data, the CIR Expert Panel concluded that ... Ammonium Thioglycolate is safe for use in hair straighteners, permanent waves, tonics, dressings, and so forth, wave sets, other non-coloring hair products, and hair dyes and colors, as described in this safety assessment, at concentrations up to 15.2% (as Thioglycolic Acid). Hairdressers should avoid skin contact and minimize consumer skin exposure.
Solubility Miscible (NTP, 1992)
Formula
C2H7NO2S
Mol. Weight
109.15
CAS #
5421-46-5
Form
Liquid
State
Ammonium thioglycolate is a colorless to faint pink liquid with a repulsive, skunk-like odor. (NTP, 1992)
See origin →
Functions
Depilatory
Hair Waving Or Straightening
Reducing
Moisturizing
Strengthens Barrier
Changes hair texture
Removes unwanted hair
Chemical reduction
Traditional Use
Developed in the early-to-mid 20th century as a reducing agent. Became the standard ingredient for chemical hair relaxing and permanent wave treatments, replacing traditional alkaline-based hair straightening methods.