Regulatory Status
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Safety Data
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Expert Verdict
Strong skin and eye irritant; highly alkaline formulations amplify irritation risk; characteristic strong sulfurous odor; potential sensitizer - though RIFM assessment found it not genotoxic and below the dermal sensitization threshold at declared use levels.. Thiol reducing agent; chemically analogous to thioglycolic acid; cleaves disulfide bonds in keratin for hair reshaping; must be formulated at controlled pH (typically 7-9.5 for general use, up to 12.7 for professional depilatory use).
Regulatory Flags
Frequently Asked Questions
Is Mercaptopropionic Acid safe in cosmetics?
Strong skin and eye irritant; highly alkaline formulations amplify irritation risk; characteristic strong sulfurous odor; potential sensitizer - though RIFM assessment found it not genotoxic and below the dermal sensitization threshold at declared use levels.. Thiol reducing agent; chemically analogous to thioglycolic acid; cleaves disulfide bonds in keratin for hair reshaping; must be formulated at controlled pH (typically 7-9.5 for general use, up to 12.7 for professional depilatory use). The EU classifies Mercaptopropionic Acid as "restricted". Safety rating: MODERATE.
Is Mercaptopropionic Acid allowed in the EU?
Mercaptopropionic Acid EU regulatory status: restricted. Maximum allowed concentration: 5%. This is based on EU Regulation 1223/2009 and its amendments.
What does Mercaptopropionic Acid do in cosmetics?
Mercaptopropionic Acid functions as: Depilatory agent, hair waving/straightening agent, reducing agent (breaks keratin disulfide bonds). It is classified as a cosmetic ingredient in our database. CAS number: 107-96-0 (3-mercaptopropionic acid).
What is the Margin of Safety for Mercaptopropionic Acid?
not established The Margin of Safety (MoS) is calculated using SCCS methodology. A MoS above 100 is generally considered safe. Use the MoS Calculator tool to calculate MoS for your specific formulation and product category.
Compliance Tools
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Related Ingredients
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