What is it?
Glyceryl thioglycolate is the essential ingredient in “acid” permanent hair waving solution, mainly used in hairdressing salons. It is also used in depilatories (hair removers) and in hair straighteners.

How can I avoid it?
Glyceryl thioglycolate can be avoided by not using permanent hair-waving solutions that contain this chemical. These solutions are found only in salons in the United States and are usually referred to as acid or hot permanents. These permanents can be identified because packages usually contain 3 bottles or containers. There is no cross-reactivity with ammonium thioglycolate, the active ingredients in alkaline permanents. Alkaline permanent wave preparations contain only 2 bottles or containers. At work, request a workplace Safety Data Sheet (SDS) to help identify potential sources of exposure.

Salon labeling, which is voluntarily being introduced in the United States, should help hairdressers and clients to avoid glyceryl thioglycolate. Hair that has been permed with this substance may cause continued exposure to this allergen for at least 3 months. This can cause long-lasting dermatitis in clients or beauticians. Glyceryl thioglycolate easily penetrates through many rubber and vinyl gloves, which makes it difficult to impossible for beauticians who are sensitive to it to continue permanent hair waving with products that contain this allergen.

  • Component in “acid” permanent wave, mainly used in hairdressing salons
  • Depilatories (hair removers)
  • Hair straighteners
Other names for Glyceryl Thioglycolate:
  • Acetic acid, mercapto-, mono ester 1,2,3 propanetriol
  • Acid permanent waves
  • Glyceryl monomercaptoacetate
  • Glyceryl monothioglycolate
  • Mercaptoacetic acid, mono ester with 1,2,3 propanetriol
  • Glyceryl mercaptoacetate
  • GMTG
  • Thioglycolic acid


How safe is it?

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