Is MEK safe in cosmetics?
MEK has a safety rating of "GOOD" in our database. EU status: permitted. 2 toxicological study endpoint(s) are available in our database.
MEK
Also known as: 2-Butanone, AI3-07540, Caswell No. 569, EINECS 201-159-0, EPA Pesticide Chemical Code 044103 (+14 more)
MEK (CAS 78-93-3) is a cosmetic cosmetic ingredient functioning as Perfuming, Solvent. NOAEL 340 mg/kg bw/day (cross-referenced against ToxValDB ECHA IUCLID); EU Regulation 1223/2009 status: permitted; GHS signal word DANGER. 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 78-93-3 →
Auto-generated CPSR Part A draft with source citations
Cross-Vertical Regulatory Divergence
MEK is classified GHS Danger (H225, H319, H336, H335, H303, H305, H315, H320) in the chemicals database but is allowed in EU cosmetics.
Source: Cosmetics: ingredients.eu_status; Chemicals: ghs_classifications.signal_word/hazard_statement_code
Function
Perfuming, Solvent
Safety Rating
GOOD
Chemistry & Identifiers
IUPAC Name
butan-2-one
InChIKey
ZWEHNKRNPOVVGH-UHFFFAOYSA-N
Regulatory Status
EU EU Status
permitted
US US Status
Not specifically regulated
For full compliance data across multiple jurisdictions, use the Substance Compliance tool.
Toxicological Studies
2 study endpoints found for MEK. NOAEL (No Observed Adverse Effect Level) values are used to calculate the Margin of Safety per SCCS methodology.
| Endpoint | Value | Route | Species | Study Type | Source |
|---|---|---|---|---|---|
| NOAEL | 490 mg/kg bw/day | oral | rat | Short Term Toxicity | COSMOS_DB |
| NOAEL | 981 mg/kg bw/day | oral | rat | Short Term Toxicity | COSMOS_DB |
GHS Hazard Classification
Globally Harmonized System classification per ECHA C&L inventory and ILO/WHO International Chemical Safety Cards.
Signal Word
DANGER
Pictograms
FlamFlameExcl markWarnCancerHealth haz
Hazard Statements
Highly flammable liquid and vapour Causes serious eye irritation May cause respiratory irritation May cause drowsiness or dizziness Suspected of damaging fertility or the unborn child May be harmful if swallowed and enters airways
Short-term Exposure Effects
The substance is irritating to the eyes and respiratory tract. The substance may cause effects on the central nervous system. Exposure could cause unconsciousness. If swallowed the substance easily enters the airways and could result in aspiration pneumonitis.
Long-term Exposure Effects
The substance defats the skin, which may cause dryness or cracking. Animal tests show that this substance possibly causes toxicity to human reproduction or development.
Routes of Exposure
The substance can be absorbed into the body by inhalation, by ingestion and through the skin.
Pre-Calculated Safety Assessment
Pre-calculated NOAEL → SED → MoS audit trail for MEK across SCCS product categories, with measured dermal absorption where available.
EPA ToxValDB — Toxicity Values
10 toxicity values from EPA ToxValDB (aggregated from CCTE, HPV, ToxRefDB, IRIS, and other regulatory dossiers).
| Endpoint | Value | Species | Route | Duration | Source |
|---|---|---|---|---|---|
| NOAEL | =589.835 mg/m3 | Human | inhalation | acute | TX TCEQ |
| NOAEL | =14866.8 mg/m3 | Rat | inhalation | subchronic | TX TCEQ |
| MRL | =2.94918 mg/m3 | Human | inhalation | - | ATSDR MRLs |
| RfD | =0.6 mg/kg-day | Human | oral | - | OW Drinking Water Standards |
| LEL | =53085.2 mg/m3 | Human | inhalation | - | DOE Protective Action Criteria |
| LOAEL | =796.278 mg/m3 | Human | inhalation | acute | Cal OEHHA REL derivations |
| LD50 | >10 mL/kg bw | Rabbit | dermal | acute | ECHA IUCLID |
| LD50 | =4.29 mL/kg bw | Rat | oral | - | ECHA IUCLID |
| LOAEL | =20000 mg/L | Rat | oral | - | ECHA IUCLID |
| LOAEL | =20000 mg/L | Rat | oral | - | ECHA IUCLID |
EU CLP Annex VI Harmonized Classification
Legally binding harmonized classification per Regulation (EC) No 1272/2008 (CLP) Annex VI.
Signal Word
Danger
Pictograms
FlammableHarmful / Irritant
Hazard Class and Category
Flam. Liq. 2; STOT SE 3; Eye Irrit. 2
Hazard Statements
- H225 Highly flammable liquid and vapour
- H336 May cause drowsiness or dizziness
- H319 Causes serious eye irritation
Inserted via ATP: CLP00
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 |
|---|---|---|---|---|---|
| HMT | - | 0 | 13500 | - | - |
Endocrine Disruptor Evidence (Expanded)
Cross-referenced EDC classifications, mechanism data, and dose-response evidence from EDLists, SIN List, and cosmetic-specific detail sources.
Suspected
Evidence: Limited
(2018)
Health effects: Yes
Affected pathways: Thyroid
Regulatory framework: REACH
Source list: II
ECHA REACH Registration
European Chemicals Agency REACH dossier and Substances of Very High Concern listing.
Registration Type
Full
Tonnage Band
100,000 - 1,000,000 tonnes
Substance Type
SUBSTANCE
SVHC Candidate
No
Hazard classification: Restricted (Annex XVII)
Expanded Dermal Absorption Data
Cross-database dermal penetration: EPA Dryad physics-based, Roberts Mendeley permeation, and SCCS-aggregated measured values.
Roberts Skin Permeation (Mendeley 2022)
MW: 72.1
Log Kow: 0.37
Log Kp: -2.3467874862246565
Log Jmax: -4.86
Source: Roberts_Cheruvu_Mendeley_2022
PubChem Annotations
Safety and regulatory annotations from PubChem (NCBI) aggregated sources.
Safety (5)
Carcinogen Classification
No indication of carcinogenicity to humans (not listed by IARC).
Source: Toxin and Toxin Target Database (T3DB)
Evidence for Carcinogenicity
Cancer Classification: Group D Not Classifiable as to Human Carcinogenicity | CLASSIFICATION: D; not classifiable as to human carcinogenicity. BASIS FOR CLASSIFICATION: Based on no human carcinogenicity data and inadequate animal data. HUMAN CARCINOGENICITY DATA: None. ANIMAL CARCINOGENICITY DATA: Inadequate.
Source: Hazardous Substances Data Bank (HSDB)
Endocrine Disruptors
Potential endocrine disrupting compound
Source: NORMAN Suspect List Exchange
ICSC Safety Card
0179
Source: ILO-WHO International Chemical Safety Cards (ICSCs)
Skin Eye Respiratory Irritation
High atm concn ... are irritating to the eyes, nose, and throat ... . | Irritates the eyes and the respiratory tract.
Source: Hazardous Substances Data Bank (HSDB)
Regulatory (2)
JECFA Number
278
Source: Joint FAO/WHO Expert Committee on Food Additives (JECFA)
JECFA Evaluation
ETHYL METHYL 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)
Function Categories & List Membership
Cosmetic/Chemical Function Categories
Adhesion/cohesion promoter
Catalyst
Degradant/impurity
Flavouring and nutrient
Fragrance
No specific technical function
Solvent
Regulatory List Membership (3)
IFRA Fragrance Transparency List
FDA Substances Added to Food (EAFUS)
Consumer Product Chemical
Expert Verdict
Expert safety assessment and concern-level summary for MEK.
Regulatory Flags
cosing-sourced
eu-permitted
fragrance
needs-enrichment
ifra_fragrance
fda_food_additive
NOAEL Studies Summary
View details ->Public NOAEL study rows linked to MEK by CAS number or substance name.
Studies
2
Lowest NOAEL
490 mg/kg bw/day
Highest NOAEL
981 mg/kg bw/day
COSMOS_DB
Known Synonyms
2-Butanone
AI3-07540
Caswell No. 569
EINECS 201-159-0
EPA Pesticide Chemical Code 044103
FEMA No. 2170
Ketone, ethyl methyl
Methylethylketone
Metyl ethyl ketone
RCRA waste number U159
Ethylmethylcetone
Metiletilcetona
Metiletilchetone
Metyloetyloketon
UNII-6PT9KLV9IO
2-Butanon
3-butanone
Aethylmethylketon
C2H5COCH3
Chemical Function
Solvent
Fragrance
Flavouring and nutrient
Adhesion/cohesion promoter
Catalyst
Regulatory Lists
air; Arts and crafts/Office supplies - fabric treatment and dye; detected; emissions; Europe
air; detected; emissions; Europe; Toys and children's products
detected; Europe; Vehicle - car interior
air; detected; emissions; Europe; Vehicle - car interior
air; detected; emissions; Europe; Other direct contact consumer goods
air; Cleaning products and household care - air freshener; detected; emissions; Europe
air; detected; emissions; Europe; Toys and children's products
air; detected; emissions; Europe; Toys and children's products
air; detected; emissions; Europe; Other direct contact consumer goods
air; Cons electronics mech appliances and machinery; detected; emissions; Europe
Cleaning products and household care - laundry and fabric treatment - laundry stain remover; detected; Europe
artificial_saliva; detected; emissions; Europe; Other indirect contact consumer goods
consumer_product; detected
consumer_product; detected; Europe
consumer_product; Europe; nondetect
air; detected; emissions; Europe; Vehicle - car interior
air; detected; emissions; Europe; Other direct contact consumer goods
air; detected; emissions; Europe; Other direct contact consumer goods
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
BUTANONE
ChEMBL ID
CHEMBL15849
Frequently Asked Questions
Is MEK allowed in the EU?
MEK EU regulatory status: permitted. This is based on EU Regulation 1223/2009 and its amendments.
What does MEK do in cosmetics?
MEK functions as: Perfuming, Solvent. It is classified as a cosmetic ingredient in our database. CAS number: 78-93-3.
What is the NOAEL for MEK?
The NOAEL (No Observed Adverse Effect Level) for MEK is 490 mg/kg bw/day based on a Short Term Toxicity study via oral route in rat. A total of 2 study endpoints are available. Source: COSMOS_DB.
Is MEK classified as hazardous under GHS?
MEK carries a GHS signal word of "DANGER". Hazard statements: Highly flammable liquid and vapour Causes serious eye irritation May cause respiratory irritation May cause drowsiness or dizziness Suspected of damaging fertility or the unborn child May be harmful if swallowed and enters airways. This classification is based on the ILO/WHO International Chemical Safety Card and ECHA C&L inventory data. Note: GHS classification applies to the pure substance — at cosmetic use concentrations, hazard thresholds may not be met.
Is MEK used outside cosmetics?
MEK 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 have different safety status in cosmetics vs industrial chemicals?
MEK is classified GHS Danger (H225, H319, H336, H335, H303, H305, H315, H320) in the chemicals database but is allowed in EU cosmetics.
Compliance Tools
Check MEK compliance across multiple jurisdictions:
Ingredient Decoder
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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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