Is Mercaptopropionic Acid safe in cosmetics?
Mercaptopropionic Acid has a safety rating of "MODERATE" in our database. EU status: restricted. US status: permitted.
Moderate
Cosmetic Ingredient
Mercaptopropionic Acid
INCI: MERCAPTOPROPIONIC ACID
Mercaptopropionic Acid (CAS 107-96-0 (3-mercaptopropionic acid)) is a cosmetic cosmetic ingredient functioning as Depilatory agent, hair waving/straightening agent, reducing agent (breaks. EU Regulation 1223/2009 status: restricted, max 5%. Industrial safety data is also available in the chemical safety database.
View industrial chemical safety profile for CAS 107-96-0 (3-mercaptopropionic acid) →
Auto-generated CPSR Part A draft with source citations
Function
Depilatory agent, hair waving/straightening agent, reducing agent (breaks keratin disulfide bonds)
Safety Rating
MODERATE
Regulatory Status
EU EU Status
restricted
EU Max Conc.
5%
US US Status
permitted
US Notes
Allowed with labeling requirements; depilatory and wave products containing mercapto acids must bear appropriate caution statements.
For full compliance data across multiple jurisdictions, use the Substance Compliance tool.
Safety Data
Margin of Safety, dermal absorption, and sensitization profile summaries for Mercaptopropionic Acid.
Calculate MoS for your specific formulation with the MoS Calculator.
Expert Verdict
Expert safety assessment and concern-level summary for Mercaptopropionic Acid.
Regulatory Flags
potential-allergen
Frequently Asked Questions
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).
Compliance Tools
Check Mercaptopropionic Acid compliance across multiple jurisdictions:
Ingredient Decoder
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82 Allergen Checker
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Substance Compliance
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MoS Calculator
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Heavy Metal Limits
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