Is MIBK (Methyl Isobutyl Ketone) safe in cosmetics?
MIBK (Methyl Isobutyl Ketone) has a safety rating of "MODERATE" in our database. EU status: prohibited. US status: permitted.
MIBK (Methyl Isobutyl Ketone)
Also known as: Methyl isobutyl ketone, 4-01-00-03305, BRN 0605399, Caswell No. 574AA, EINECS 203-550-1 (+14 more)
INCI: MIBK
MIBK (Methyl Isobutyl Ketone) (CAS 108-10-1) is a cosmetic cosmetic ingredient functioning as Denaturant, fragrance ingredient, solvent. NOAEL 50 mg/kg bw/day (cross-referenced against ToxValDB ECHA IUCLID); EU Regulation 1223/2009 status: prohibited. 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 108-10-1 →
Auto-generated CPSR Part A draft with source citations
Cross-Vertical Regulatory Divergence
MIBK (Methyl Isobutyl Ketone) is prohibited in EU cosmetics but has active industrial GHS classifications (H225, H319, H332, H335, H336, H351, H320, H331).
Source: Cosmetics: ingredients.eu_status; Chemicals: ghs_classifications.signal_word/hazard_statement_code
Function
Denaturant, fragrance ingredient, solvent
Safety Rating
MODERATE
Chemistry & Identifiers
IUPAC Name
4-methylpentan-2-one
InChIKey
NTIZESTWPVYFNL-UHFFFAOYSA-N
Regulatory Status
EU EU Status
prohibited
US US Status
permitted
US Notes
Allowed with limitations - the CIR Expert Panel concluded MIBK is safe as used in nail care products and as an alcohol denaturant in cosmetics at current practices of use and concentration
For full compliance data across multiple jurisdictions, use the Substance Compliance tool.
Safety Data
Margin of Safety, dermal absorption, and sensitization profile summaries for MIBK (Methyl Isobutyl Ketone).
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 and the vapour are irritating to the eyes, skin and respiratory tract. If this liquid is swallowed, aspiration into the lungs may result in chemical pneumonitis. The substance may cause effects on the central nervous system at high concentrations. This may result in narcosis.
Long-term Exposure Effects
Repeated or prolonged contact with skin may cause dermatitis.
Routes of Exposure
The substance can be absorbed into the body by inhalation of its vapour and by ingestion.
Pre-Calculated Safety Assessment
Pre-calculated NOAEL → SED → MoS audit trail for MIBK (Methyl Isobutyl Ketone) across SCCS product categories, with measured dermal absorption where available.
IARC Carcinogenicity
International Agency for Research on Cancer (WHO) monograph evaluation.
IARC Group
2B
Volume
101
Evaluation Year
2011
EU CLP Annex VI Harmonized Classification
Legally binding harmonized classification per Regulation (EC) No 1272/2008 (CLP) Annex VI.
Signal Word
Danger
Pictograms
FlammableHealth HazardHarmful / Irritant
Hazard Class and Category
Flam. Liq. 2; Carc. 2; Acute Tox. 4; STOT SE 3; Eye Irrit. 2
Hazard Statements
- H225 Highly flammable liquid and vapour
- H351 Suspected of causing cancer
- H332 Harmful if inhaled
- H336 May cause drowsiness or dizziness
- H319 Causes serious eye irritation
Specific Concentration Limits / M-factors
inhalation: ATE = 11.0 mg/L vapours
Inserted via ATP: ATP17
ECHA REACH Registration
European Chemicals Agency REACH dossier and Substances of Very High Concern listing.
Registration Type
Full
Tonnage Band
10,000 - 100,000 tonnes
Substance Type
SUBSTANCE
SVHC Candidate
No
Hazard classification: Restricted (Annex XVII)
EU CosIng Annex Listing
European Commission CosIng database Annex references per Regulation (EC) No 1223/2009.
Annex II — Prohibited
Ref: 1689
(EU) 2022/1531
CMR: Carcinogenic Cat. 2()
Expanded Jurisdictional Detail
Additional regulatory detail beyond the 7-jurisdiction summary: Saudi SFDA, Korea MFDS, ASEAN ACD, Japan/Korea, Brazil/India, and cross-jurisdictional restriction entries.
SA Saudi SFDA (II - Prohibited)
ASEAN Cosmetic Directive (II)
Ref: 1689
Additional Jurisdictional Restrictions (1)
| Jurisdiction | Status | Max % | Product Type |
|---|---|---|---|
| TH | banned | - | All cosmetic products prohibited |
PubChem Annotations
Safety and regulatory annotations from PubChem (NCBI) aggregated sources.
Safety (6)
Carcinogen Classification
Methyl isobutyl ketone | Group 2B: Possibly carcinogenic to humans | Volume 101: (2012) Some Chemicals Present in Industrial and Consumer Products, Food and Drinking-water
Source: International Agency for Research on Cancer (IARC)
Carcinogen Classification
Methyl isobutyl ketone | TR-538: Toxicology and Carcinogenesis Studies of Methyl Isobutyl Ketone (CASRN 108-10-1) in F344/N Rats and B6C3F1 Mice (Inhalation Studies) (2007 ) | 09/27/05 | Some Evidence | Equivocal Evidence | Some Evidence | Some Evidence | Under the conditions of these 2-year dermal studies, there was no evidence of carcinogenic activity of bis(2-chloroethoxy)methane in ma
Source: NTP Technical Reports
Evidence for Carcinogenicity
Cancer in humans: No data were available to the Working Group. Cancer in experimental animals: There is sufficient evidence in experimental animals for the carcinogenicity of methyl isobutyl ketone. Overall evaluation: Methyl isobutyl ketone is possibly carcinogenic to humans (Group 2B). | A3; Confirmed animal carcinogen with unknown relevance to humans.
Source: Hazardous Substances Data Bank (HSDB)
Evidence for Carcinogenicity
Male rat-specific kidney tumors can occur after exposures to a structurally diverse group of substances or their metabolites. This arises from binding to α2u, a low-molecular-weight protein. Examples of these substances include 1,4-dichlorobenzene (and -2,5-dichlorophenol, its metabolite), d-limonene (and d-limonene 2-5-oxide, its metabolite), methyl isobutyl ketone (MIBK), 2,2,4-trimethylpentane
Source: Pertti (Bert) Hakkinen's Toxicology and Other Annotations
ICSC Safety Card
0511
Source: ILO-WHO International Chemical Safety Cards (ICSCs)
Regulatory (4)
JECFA Number
301
Source: Joint FAO/WHO Expert Committee on Food Additives (JECFA)
JECFA Evaluation
4-METHYL-2-PENTANONE | 1998 | No safety concern at current levels of intake when used as a flavouring agent | TRS 891-JECFA 51/59 | FAS 42-JECFA 51/235
Source: Joint FAO/WHO Expert Committee on Food Additives (JECFA)
JECFA Evaluation
METHYL ISOBUTYL KETONE | 1998 | No safety concern at current levels of intake when used as a flavouring agent | TRS 891-JECFA 51/59 | FAS 42-JECFA 51/235
Source: Joint FAO/WHO Expert Committee on Food Additives (JECFA)
JECFA Evaluation
MIBK | 1998 | No safety concern at current levels of intake when used as a flavouring agent | TRS 891-JECFA 51/59 | FAS 42-JECFA 51/235
Source: Joint FAO/WHO Expert Committee on Food Additives (JECFA)
Function Categories & List Membership
Cosmetic/Chemical Function Categories
Flavouring and nutrient
Fragrance
Solvent
Regulatory List Membership (4)
California Proposition 65 (OEHHA)
IFRA Fragrance Transparency List
FDA Substances Added to Food (EAFUS)
Consumer Product Chemical
Expert Verdict
Expert safety assessment and concern-level summary for MIBK (Methyl Isobutyl Ketone).
Regulatory Flags
fragrance-component
prop65
ifra_fragrance
fda_food_additive
Known Synonyms
Methyl isobutyl ketone
4-01-00-03305
BRN 0605399
Caswell No. 574AA
EINECS 203-550-1
EPA Pesticide Chemical Code 044105
FEMA No. 2731
FEMA Number 2731
Hexanone
Isohexanone
Ketone, isobutyl methyl
RCRA waste number U161
Shell MIBK
4-Methyl-pentan-2-on
4-Metilpentan-2-one
Isobutyl-methylketon
Methyl-isobutyl-cetone
Methylisobutylketon
Metilisobutilchetone
Chemical Function
Solvent
Fragrance
Flavouring and nutrient
Regulatory Lists
IFRA Transparency
consumer_product
detected; Europe; Other direct contact consumer goods
Europe
air; Arts and crafts/Office supplies - children's art and toys - modeling clay; detected; emissions; Europe
inert_ingredient; non_food_use; Pesticides
OEHHA Proposition 65 (3/2019)
food_additive; Substances Added to Food (formerly EAFUS) (2/2019)
OEHHA Proposition 65 (1/2023)
OEHHA Proposition 65 (3/2019)
OEHHA Proposition 65 (1/2023)
detected; drinking_water; MN Chemical Screening
Cleaning products and household care - laundry and fabric treatment - laundry stain remover; detected; Europe
Cleaning products and household care - laundry and fabric treatment - laundry stain remover; detected; Europe
artificial_saliva; detected; emissions; Europe; Toys and children's products
Europe; Toys and children's products
air; detected; emissions; Europe; Other direct contact consumer goods
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.
Compound
METHYL ISOBUTYL KETONE
ChEMBL ID
CHEMBL285323
Max Phase
-1
Frequently Asked Questions
Is MIBK (Methyl Isobutyl Ketone) allowed in the EU?
MIBK (Methyl Isobutyl Ketone) EU regulatory status: prohibited. This is based on EU Regulation 1223/2009 and its amendments.
What does MIBK (Methyl Isobutyl Ketone) do in cosmetics?
MIBK (Methyl Isobutyl Ketone) functions as: Denaturant, fragrance ingredient, solvent. It is classified as a cosmetic ingredient in our database. CAS number: 108-10-1.
Is MIBK (Methyl Isobutyl Ketone) used outside cosmetics?
MIBK (Methyl Isobutyl Ketone) 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 MIBK (Methyl Isobutyl Ketone) have different safety status in cosmetics vs industrial chemicals?
MIBK (Methyl Isobutyl Ketone) is prohibited in EU cosmetics but has active industrial GHS classifications (H225, H319, H332, H335, H336, H351, H320, H331).
Compliance Tools
Check MIBK (Methyl Isobutyl Ketone) 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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