Is Thiolactic Acid safe in cosmetics?
Thiolactic Acid has a safety rating of "MODERATE" in our database. EU status: restricted. US status: permitted.
Moderate
Cosmetic Ingredient
Thiolactic Acid
INCI: THIOLACTIC ACID
Thiolactic Acid (CAS 79-42-5) is a cosmetic cosmetic ingredient functioning as Depilatory, Hair Waving/Straightening, Reducing Agent. NOAEL 150 mg/kg bw/day (cross-referenced against ToxValDB ECHA IUCLID); EU Regulation 1223/2009 status: restricted. Industrial safety data is also available in the chemical safety database. Same-CAS public records also appear in industrial chemical safety and pharmaceutical data.
View industrial chemical safety profile for CAS 79-42-5 →
Auto-generated CPSR Part A draft with source citations
Cross-Vertical Regulatory Divergence
Thiolactic Acid is classified GHS Danger (H301, H311, H314, H330) in the chemicals database but is restricted in EU cosmetics.
Source: Cosmetics: ingredients.eu_status; Chemicals: ghs_classifications.signal_word/hazard_statement_code
Function
Depilatory, Hair Waving/Straightening, Reducing Agent
Safety Rating
MODERATE
Chemistry & Identifiers
IUPAC Name
2-sulfanylpropanoic acid
InChIKey
PMNLUUOXGOOLSP-UHFFFAOYSA-N
Regulatory Status
EU EU Status
restricted
US US Status
permitted
US Notes
Permitted; general cosmetic ingredient
For full compliance data across multiple jurisdictions, use the Substance Compliance tool.
Safety Data
Margin of Safety, dermal absorption, and sensitization profile summaries for Thiolactic Acid.
Calculate MoS for your specific formulation with the MoS Calculator.
Pre-Calculated Safety Assessment
Pre-calculated NOAEL → SED → MoS audit trail for Thiolactic Acid across SCCS product categories, with measured dermal absorption where available.
HRIPT Human Patch Test Studies
1 human repeat insult patch test aggregated from dermatological literature.
| Test Type | N | Sensitized | Dose µg/cm² | NESIL µg/cm² | Potency |
|---|---|---|---|---|---|
| HRIPT | - | 0 | 1700.57 | - | - |
ECHA REACH Registration
European Chemicals Agency REACH dossier and Substances of Very High Concern listing.
Registration Type
Full
Tonnage Band
10 - 100 tonnes
Substance Type
SUBSTANCE
SVHC Candidate
No
PubChem Annotations
Safety and regulatory annotations from PubChem (NCBI) aggregated sources.
Regulatory (5)
JECFA Number
551
Source: Joint FAO/WHO Expert Committee on Food Additives (JECFA)
JECFA Evaluation
2-MERCAPTOPROPIONIC ACID | 1999 | No safety concern at current levels of intake when used as a flavouring agent | TRS 896-JECFA 53/32 | FAS 44-JECFA 53/125
Source: Joint FAO/WHO Expert Committee on Food Additives (JECFA)
JECFA Evaluation
alpha-MERCAPTOPROPANOIC ACID | 1999 | No safety concern at current levels of intake when used as a flavouring agent | TRS 896-JECFA 53/32 | FAS 44-JECFA 53/125
Source: Joint FAO/WHO Expert Committee on Food Additives (JECFA)
JECFA Evaluation
THIOLACTIC ACID | 1999 | No safety concern at current levels of intake when used as a flavouring agent | TRS 896-JECFA 53/32 | FAS 44-JECFA 53/125
Source: Joint FAO/WHO Expert Committee on Food Additives (JECFA)
JECFA Evaluation
2-THIOLPROPIONIC ACID | 1999 | No safety concern at current levels of intake when used as a flavouring agent | TRS 896-JECFA 53/32 | FAS 44-JECFA 53/125
Source: Joint FAO/WHO Expert Committee on Food Additives (JECFA)
Function Categories & List Membership
Cosmetic/Chemical Function Categories
Antioxidant
Deodorizer
Depilatory
Flavouring and nutrient
Fragrance
Hair waving or straightening
Reducing agent
Regulatory List Membership (2)
IFRA Fragrance Transparency List
FDA Substances Added to Food (EAFUS)
Expert Verdict
Expert safety assessment and concern-level summary for Thiolactic Acid.
Regulatory Flags
ifra_fragrance
fda_food_additive
Chemical Function
Antioxidant
Deodorizer
Reducing agent
Depilatory
Hair waving or straightening
Fragrance
Regulatory Lists
IFRA Transparency
Europe
food_additive; Substances Added to Food (formerly EAFUS) (2/2019)
Australian Status
AICIS status: listed
Cross-Vertical Safety Context
Same-CAS public records found in pharmaceutical data.
SOURCE
ChEMBL / DrugCentral / FAERS
DB_PHARMA CAS match
Pharmaceutical Data
Same-CAS rows from the pharmaceutical spoke database.
ChEMBL ID
CHEMBL2158192
Frequently Asked Questions
Is Thiolactic Acid allowed in the EU?
Thiolactic Acid EU regulatory status: restricted. This is based on EU Regulation 1223/2009 and its amendments.
What does Thiolactic Acid do in cosmetics?
Thiolactic Acid functions as: Depilatory, Hair Waving/Straightening, Reducing Agent. It is classified as a cosmetic ingredient in our database. CAS number: 79-42-5.
Is Thiolactic Acid used outside cosmetics?
Thiolactic Acid also appears in industrial chemical safety and pharmaceutical data. The cross-vertical cards on this page render same-CAS public rows from the matched databases.
Does Thiolactic Acid have different safety status in cosmetics vs industrial chemicals?
Thiolactic Acid is classified GHS Danger (H301, H311, H314, H330) in the chemicals database but is restricted in EU cosmetics.
Compliance Tools
Check Thiolactic Acid compliance across multiple jurisdictions:
Ingredient Decoder
Paste a full ingredient list for instant analysis
82 Allergen Checker
Check for EU declarable fragrance allergens
Substance Compliance
Check compliance across multiple jurisdictions
MoS Calculator
Calculate Margin of Safety using SCCS methodology
Heavy Metal Limits
Compare limits across jurisdictions
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