Is MEK Peroxides (Methyl Ethyl Ketone Peroxide / MEKP) safe in cosmetics?
MEK Peroxides (Methyl Ethyl Ketone Peroxide / MEKP) has a safety rating of "MODERATE" in our database. EU status: permitted. US status: permitted.
MEK Peroxides (Methyl Ethyl Ketone Peroxide / MEKP)
Also known as: Methyl ethyl ketone peroxide, Chaloxyd MEKP HA 1, EINECS 215-661-2, Esperfoam FR, HI-Point PD-1 (+9 more)
INCI: NOT A RECOGNIZED COSMETIC INCI NAME - THIS IS AN INDUSTRIAL CHEMICAL
MEK Peroxides (Methyl Ethyl Ketone Peroxide / MEKP) (CAS 1338-23-4) is a cosmetic cosmetic ingredient functioning as Oxidizing agent / catalyst (industrial use: initiator for room-temperature. NOAEL 150 mg/kg bw/day (cross-referenced against ToxValDB ECHA IUCLID); EU Regulation 1223/2009 status: permitted. 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 1338-23-4 →
Auto-generated CPSR Part A draft with source citations
Cross-Vertical Regulatory Divergence
MEK Peroxides (Methyl Ethyl Ketone Peroxide / MEKP) is classified GHS Danger (H242, H302, H314, H318, H332, H312, H335, H341) in the chemicals database but is allowed in EU cosmetics.
Source: Cosmetics: ingredients.eu_status; Chemicals: ghs_classifications.signal_word/hazard_statement_code
Function
Oxidizing agent / catalyst (industrial use: initiator for room-temperature curing of unsaturated polyester resins)
Safety Rating
MODERATE
Chemistry & Identifiers
IUPAC Name
2-hydroperoxy-2-(2-hydroperoxybutan-2-ylperoxy)butane
InChIKey
WFUGQJXVXHBTEM-UHFFFAOYSA-N
Regulatory Status
EU EU Status
permitted
US US Status
permitted
US Notes
Not recognized as a cosmetic ingredient. No GRAS or cosmetic-use history. Would require full safety substantiation if anyone attempted cosmetic use, which is essentially unprecedented.
For full compliance data across multiple jurisdictions, use the Substance Compliance tool.
Safety Data
Margin of Safety, dermal absorption, and sensitization profile summaries for MEK Peroxides (Methyl Ethyl Ketone Peroxide / MEKP).
Calculate MoS for your specific formulation with the MoS Calculator.
GHS Hazard Classification
Globally Harmonized System classification per ECHA C&L inventory and ILO/WHO International Chemical Safety Cards.
Short-term Exposure Effects
The substance is corrosive to the eyes, skin and respiratory tract. Corrosive on ingestion.
Routes of Exposure
The substance can be absorbed into the body by inhalation and by ingestion.
Pre-Calculated Safety Assessment
Pre-calculated NOAEL → SED → MoS audit trail for MEK Peroxides (Methyl Ethyl Ketone Peroxide / MEKP) across SCCS product categories, with measured dermal absorption where available.
ECHA REACH Registration
European Chemicals Agency REACH dossier and Substances of Very High Concern listing.
Registration Type
Full
Tonnage Band
Ceased manufacture
Substance Type
SUBSTANCE
SVHC Candidate
No
PubChem Annotations
Safety and regulatory annotations from PubChem (NCBI) aggregated sources.
Safety (3)
Carcinogen Classification
No indication of carcinogenicity to humans (not listed by IARC).
Source: Toxin and Toxin Target Database (T3DB)
ICSC Safety Card
1028
Source: ILO-WHO International Chemical Safety Cards (ICSCs)
Skin Eye Respiratory Irritation
... Methyl ethyl ketone peroxide ... /is/ extremely irritating and corrosive to the eyes, with risk of blindness ... .
Source: Hazardous Substances Data Bank (HSDB)
Function Categories & List Membership
Cosmetic/Chemical Function Categories
Catalyst
Chemical reaction regulator
Hardener
Regulatory List Membership (1)
FDA Indirect Food Contact Additives
Expert Verdict
Expert safety assessment and concern-level summary for MEK Peroxides (Methyl Ethyl Ketone Peroxide / MEKP).
Known Synonyms
Methyl ethyl ketone peroxide
Chaloxyd MEKP HA 1
EINECS 215-661-2
Esperfoam FR
HI-Point PD-1
Lupersol DEL
Methylethylketonhydroperoxide
NCI-C55447
Quickset Extra
Quickset super
RCRA waste number U160
Sprayset MEKP
Thermacure
UNII-W2545087UL
Chemical Function
Catalyst
Regulatory Lists
active_ingredient; Europe; Pesticides
Indirect additives food contact (10/2018)
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
CHEMBL1562553
Frequently Asked Questions
Is MEK Peroxides (Methyl Ethyl Ketone Peroxide / MEKP) allowed in the EU?
MEK Peroxides (Methyl Ethyl Ketone Peroxide / MEKP) EU regulatory status: permitted. This is based on EU Regulation 1223/2009 and its amendments.
What does MEK Peroxides (Methyl Ethyl Ketone Peroxide / MEKP) do in cosmetics?
MEK Peroxides (Methyl Ethyl Ketone Peroxide / MEKP) functions as: Oxidizing agent / catalyst (industrial use: initiator for room-temperature curing of unsaturated polyester resins). It is classified as a cosmetic ingredient in our database. CAS number: 1338-23-4.
Is MEK Peroxides (Methyl Ethyl Ketone Peroxide / MEKP) used outside cosmetics?
MEK Peroxides (Methyl Ethyl Ketone Peroxide / MEKP) 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 MEK Peroxides (Methyl Ethyl Ketone Peroxide / MEKP) have different safety status in cosmetics vs industrial chemicals?
MEK Peroxides (Methyl Ethyl Ketone Peroxide / MEKP) is classified GHS Danger (H242, H302, H314, H318, H332, H312, H335, H341) in the chemicals database but is allowed in EU cosmetics.
Compliance Tools
Check MEK Peroxides (Methyl Ethyl Ketone Peroxide / MEKP) 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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