Is Styrene Oxide safe in cosmetics?
Styrene Oxide has a safety rating of "POOR" in our database. EU status: prohibited. US status: permitted. 2 toxicological study endpoint(s) are available in our database.
Styrene Oxide
Also known as: Oxirane, phenyl-, 5-17-01-00577, Benzene, (1,2-epoxyethyl)-, BRN 0108582, EINECS 202-476-7 (+11 more)
INCI: STYRENE OXIDE (NOT AN ESTABLISHED INCI INGREDIENT)
Styrene Oxide (CAS 96-09-3) is a cosmetic cosmetic ingredient functioning as No legitimate cosmetic function — industrial chemical intermediate. Reported NOAEL =128 mg/kg bw/day in Mouse (ToxValDB_ECHA_IUCLID); EU Regulation 1223/2009 status: prohibited; 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 96-09-3 →
Auto-generated CPSR Part A draft with source citations
Cross-Vertical Regulatory Divergence
Styrene Oxide is prohibited in EU cosmetics but has active industrial GHS classifications (H311, H312, H315, H317, H319, H331, H340, H341).
Source: Cosmetics: ingredients.eu_status; Chemicals: ghs_classifications.signal_word/hazard_statement_code
Function
No legitimate cosmetic function — industrial chemical intermediate
Safety Rating
POOR
Chemistry & Identifiers
IUPAC Name
2-phenyloxirane
InChIKey
AWMVMTVKBNGEAK-UHFFFAOYSA-N
Regulatory Status
EU EU Status
prohibited
US US Status
permitted
US Notes
Not approved for cosmetic use. Classified as a hazardous substance
For full compliance data across multiple jurisdictions, use the Substance Compliance tool.
Safety Data
Margin of Safety, dermal absorption, and sensitization profile summaries for Styrene Oxide.
Calculate MoS for your specific formulation with the MoS Calculator.
Toxicological Studies
2 study endpoints found for Styrene Oxide. 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 | =128 mg/kg bw/day | oral | Mouse | chronic | ToxValDB_ECHA_IUCLID |
| NOAEL | =300 mg/kg bw/day | oral | Mouse | chronic | ToxValDB_ECHA_IUCLID |
GHS Hazard Classification
Globally Harmonized System classification per ECHA C&L inventory and ILO/WHO International Chemical Safety Cards.
Signal Word
DANGER
Pictograms
Excl markWarnCancerHealth haz
Hazard Statements
Combustible liquid Harmful if swallowed Causes skin irritation Causes eye irritation Suspected of causing genetic defects May cause cancer
Short-term Exposure Effects
The substance is irritating to the eyes and skin. The substance may cause effects on the central nervous system. Exposure could cause lowering of consciousness.
Long-term Exposure Effects
This substance is probably carcinogenic to humans.
Routes of Exposure
The substance can be absorbed into the body by inhalation, through the skin and by ingestion.
IARC Carcinogenicity
International Agency for Research on Cancer (WHO) monograph evaluation.
IARC Group
2A
Volume
Sup 7, 60, 121
Evaluation Year
2018
NB Overall evaluation upgraded to Group 2A with supporting evidence from other relevant data
EU CLP Annex VI Harmonized Classification
Legally binding harmonized classification per Regulation (EC) No 1272/2008 (CLP) Annex VI.
Signal Word
Danger
Pictograms
Health HazardHarmful / Irritant
Hazard Class and Category
Carc. 1B; Acute Tox. 4 *; Eye Irrit. 2
Hazard Statements
- H350 May cause cancer
- H312 Harmful in contact with skin
- H319 Causes serious eye irritation
Inserted via ATP: CLP00
ECHA REACH Registration
European Chemicals Agency REACH dossier and Substances of Very High Concern listing.
Registration Type
Full
Tonnage Band
100 - 1,000 tonnes
Substance Type
SUBSTANCE; GROUP
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: 656
(EC) 2009/1223
CMR: Carcinogenic Cat. 1B()
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: 656
BRIN Brazil/India Cosmetics
Brazil: Prohibited
India: Prohibited (GNRAS)
PubChem Annotations
Safety and regulatory annotations from PubChem (NCBI) aggregated sources.
Safety (4)
Carcinogen Classification
Styrene-7,8-oxide | Group 2A: Probably carcinogenic to humans | Volume Sup 7: Overall Evaluations of Carcinogenicity: An Updating of IARC Monographs Volumes 1 to 42, 1987; 440 pages; ISBN 92-832-1411-0 (out of print) | Volume 60: (1994) Some Industrial Chemicals | Volume 121: (2019) Styrene, Styrene-7,8-oxide, and Quinoline | NB Overall evaluation upgraded to Group 2A with supporting evidence from
Source: International Agency for Research on Cancer (IARC)
Evidence for Carcinogenicity
Evaluation: There is inadequate evidence in humans for the carcinogenicity of styrene-7,8-oxide. There is sufficient evidence in experimental animals for the carcinogenicity of styrene-7,8-oxide. Overall evaluation: Styrene-7,8-oxide is probably carcinogenic to humans (Group 2A). | Styrene-7,8-oxide: reasonably anticipated to be a human carcinogen.
Source: Hazardous Substances Data Bank (HSDB)
ICSC Safety Card
1201
Source: ILO-WHO International Chemical Safety Cards (ICSCs)
Skin Eye Respiratory Irritation
...Styrene oxide is capable of causing moderate skin irritation and skin sensitization. These effects may result from single or repeated contact with undiluted material and with solutions as dilute as 1%. Experience indicates that persons who have become hypersensitive may react rather severely to contact with the vapor as well as with the liquid material. | Acute exposure to styrene oxide causes
Source: Hazardous Substances Data Bank (HSDB)
Function Categories & List Membership
Cosmetic/Chemical Function Categories
Fragrance
No specific technical function
Regulatory List Membership (5)
California Proposition 65 (OEHHA)
EU Banned in Cosmetics
IFRA Fragrance Transparency List
FDA Indirect Food Contact Additives
EU CosIng Cosmetics Ingredient Database
Expert Verdict
Expert safety assessment and concern-level summary for Styrene Oxide.
Regulatory Flags
endocrine_disruptor
prop65
eu_banned_cosmetics
ifra_fragrance
eu_cosing_listed
NOAEL Studies Summary
View details ->Public NOAEL study rows linked to Styrene Oxide by CAS number or substance name.
Studies
2
Lowest NOAEL
128 mg/kg bw/day
Highest NOAEL
300 mg/kg bw/day
ToxValDB_ECHA_IUCLID
Known Synonyms
Oxirane, phenyl-
5-17-01-00577
Benzene, (1,2-epoxyethyl)-
BRN 0108582
EINECS 202-476-7
Epoxyethyl benzene
NCI-C54977
Fenyloxiran
UNII-9QH06NGT6O
1,2-epoxy-1-phenylethane
1-phenyloxirane
Styrene-7,8-oxide
alpha,beta-epoxystyrene
epoxyethylbenzene
phenethylene oxide
phenyl oxirane
Chemical Function
Fragrance
No specific technical function
Regulatory Lists
banned; Europe; Personal care
IFRA Transparency
Cons electronics mech appliances and machinery; Europe
Indirect additives food contact (10/2018)
OEHHA Proposition 65 (3/2019)
OEHHA Proposition 65 (1/2023)
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
CHEMBL1605493
Frequently Asked Questions
Is Styrene Oxide allowed in the EU?
Styrene Oxide EU regulatory status: prohibited. This is based on EU Regulation 1223/2009 and its amendments.
What does Styrene Oxide do in cosmetics?
Styrene Oxide functions as: No legitimate cosmetic function — industrial chemical intermediate. It is classified as a cosmetic ingredient in our database. CAS number: 96-09-3.
What is the NOAEL for Styrene Oxide?
The NOAEL (No Observed Adverse Effect Level) for Styrene Oxide is =128 mg/kg bw/day based on a chronic study via oral route in Mouse. A total of 2 study endpoints are available. Source: ToxValDB_ECHA_IUCLID.
Is Styrene Oxide classified as hazardous under GHS?
Styrene Oxide carries a GHS signal word of "DANGER". Hazard statements: Combustible liquid Harmful if swallowed Causes skin irritation Causes eye irritation Suspected of causing genetic defects May cause cancer. 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 Styrene Oxide used outside cosmetics?
Styrene Oxide 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 Styrene Oxide have different safety status in cosmetics vs industrial chemicals?
Styrene Oxide is prohibited in EU cosmetics but has active industrial GHS classifications (H311, H312, H315, H317, H319, H331, H340, H341).
Compliance Tools
Check Styrene Oxide compliance across multiple jurisdictions:
Ingredient Decoder
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Check for EU declarable fragrance allergens
Substance Compliance
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MoS Calculator
Calculate Margin of Safety using SCCS methodology
Heavy Metal Limits
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