Moderate Cosmetic Ingredient NOAEL Data GHS Classified

STYRENE

Also known as: Ethenylbenzene, Phenylethylene, Vinylbenzene, Benzene, vinyl-, Bulstren K-525-19 (+15 more)

STYRENE (CAS 100-42-5) is a cosmetic cosmetic ingredient functioning as Solvent. NOAEL 0.21 mg/kg bw/day (cross-referenced against ToxValDB ECHA IUCLID); EU Regulation 1223/2009 status: restricted, max II/1575; 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, pharmaceutical, and food safety data.

View industrial chemical safety profile for CAS 100-42-5 →

Auto-generated CPSR Part A draft with source citations
Function
Solvent
Safety Rating
MODERATE

Chemistry & Identifiers

Formula
C8H8
MW
104.15 g/mol
EC Number
202-851-5
PubChem CID
7501
IUPAC Name
styrene
InChIKey
PPBRXRYQALVLMV-UHFFFAOYSA-N

Regulatory Status

EU EU Status restricted
EU Max Conc. II/1575
US US Status Not specifically regulated

For full compliance data across multiple jurisdictions, use the Substance Compliance tool.

Toxicological Studies

10 study endpoints found for STYRENE. 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 21 mg/kg bw/day oral rat Carcinogenicity COSMOS_DB
NOAEL 25 mg/kg bw/day oral rat Multigeneration Reproductive COSMOS_DB
NOAEL 34.6 mg/kg bw/day oral rat Short Term Toxicity COSMOS_DB
NOAEL 36 mg/kg bw/day oral mouse Special Toxicology Study COSMOS_DB
NOAEL 100 mg/kg bw/day oral rat Neurotoxicity COSMOS_DB
NOAEL 114 mg/kg bw/day oral guinea pig Special Toxicology Study COSMOS_DB
NOAEL 229 mg/kg bw/day oral rat Special Toxicology Study COSMOS_DB
NOAEL 250 mg/kg bw/day oral rat Carcinogenicity COSMOS_DB
NOAEL 300 mg/kg bw/day oral mouse Carcinogenicity COSMOS_DB
NOAEL 357 mg/kg bw/day oral rat Neurotoxicity 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
Flammable liquid and vapour Harmful if inhaled Causes skin and eye irritation Suspected of causing cancer Causes damage to the central nervous system and the liver through prolonged or repeated exposure Toxic to aquatic life
Short-term Exposure Effects
The substance is 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. Exposure at high levels could cause unconsciousness.
Long-term Exposure Effects
The substance defats the skin, which may cause dryness or cracking. The substance may have effects on the central nervous system. Exposure to the substance may increase noise-induced hearing loss. This substance is possibly carcinogenic to humans. See Notes.
Routes of Exposure
The substance can be absorbed into the body by inhalation of its vapour.

Pre-Calculated Safety Assessment

Pre-calculated NOAEL → SED → MoS audit trail for STYRENE 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
LEL =511.178 mg/m3 Mouse inhalation chronic EPA TSCA 8e
MRL =21.2991 mg/m3 Human inhalation - ATSDR MRLs
MRL =0.851963 mg/m3 Human inhalation - ATSDR MRLs
MRL =0.1 mg/kg-day Human oral - ATSDR MRLs
NOAEL =217.251 mg/m3 Human inhalation acute Cal OEHHA REL derivations
LEL =38338.4 mg/m3 Human inhalation - DOE Protective Action Criteria
NOAEL =12 mg/kg-day Rat oral chronic (developmental) Health Canada
TDI =0.12 mg/kg-day Human oral chronic (developmental) Health Canada
LEL =851.963 mg/m3 Human inhalation acute NIOSH IDLH
LEL =1601.69 mg/m3 Human inhalation acute NIOSH IDLH

IARC Carcinogenicity

International Agency for Research on Cancer (WHO) monograph evaluation.

IARC Group
2A
Volume
60, 82, 121
Evaluation Year
2018

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. 3; Repr. 2; Acute Tox. 4 *; STOT RE 1; Skin Irrit. 2; Eye Irrit. 2
Hazard Statements
  • H226 Flammable liquid and vapour
  • H361d
  • H332 Harmful if inhaled
  • H372 (hearing organs)
  • H315 Causes skin irritation
  • H319 Causes serious eye irritation
Specific Concentration Limits / M-factors
*

Inserted via ATP: ATP06

ECHA REACH Registration

European Chemicals Agency REACH dossier and Substances of Very High Concern listing.

Registration Type
Full
Tonnage Band
1,000,000 - 10,000,000 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: 1575
(EU) 2019/831
CMR: Reprotoxic 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: 1575
BRIN Brazil/India Cosmetics
India: Prohibited (GNRAS)
Additional Jurisdictional Restrictions (2)
Jurisdiction Status Max % Product Type
ID banned - All cosmetic products prohibited
ID banned 0% All cosmetic products

PubChem Annotations

Safety and regulatory annotations from PubChem (NCBI) aggregated sources.

Safety (7)
Carcinogen Classification
2B, possibly carcinogenic to humans. (L135)
Source: Toxin and Toxin Target Database (T3DB)
Carcinogen Classification
Styrene | Group 2A: Probably carcinogenic to humans | Volume 60: (1994) Some Industrial Chemicals | Volume 82: (2002) Some Traditional Herbal Medicines, Some Mycotoxins, Naphthalene and Styrene | Volume 121: (2019) Styrene, Styrene-7,8-oxide, and Quinoline
Source: International Agency for Research on Cancer (IARC)
Carcinogen Classification
Styrene | TR-185: Bioassay of Styrene for Possible Carcinogenicity (CASRN 100-42-5) (1979 ) | 10/25/78 | No Evidence | No Evidence | Equivocal Evidence | No Evidence | The findings of an increased incidence of a combination of adenomas and carcinomas of the lung provided suggestive evidence for the carcinogenicity of styrene in male B6C3F1 mice. However, it is concluded that, under the co
Source: NTP Technical Reports
Evidence for Carcinogenicity
Styrene is reasonably anticipated to be a human carcinogen based on limited evidence of carcinogenicity from studies in humans, sufficient evidence of carcinogenicity from studies in experimental animals, and supporting data on mechanisms of carcinogenesis. | Evaluation: There is limited evidence in humans for the carcinogenicity of styrene. There is limited evidence in experimental animals for th
Source: Hazardous Substances Data Bank (HSDB)
Endocrine Disruptors
Potential endocrine disrupting compound
Source: NORMAN Suspect List Exchange
Regulatory (1)
JECFA Evaluation
STYRENE | 1984 | The available data indicate that styrene may have carcinogenic activity in mice; however, styrene has not demonstrated carcinogenic activity in rats or in humans. On the basis of the lack of evidence of carcinogenicity from epidemiology studies, the Committee considered it appropriate to establish a PMTDI of 0.04 mg/kg bw/d for styrene based on the NOEL of 7.7 mg/kg bw/d from a 2-
Source: Joint FAO/WHO Expert Committee on Food Additives (JECFA)

Function Categories & List Membership

Cosmetic/Chemical Function Categories
Binder Flavouring and nutrient Fragrance Monomers Viscosity modifier
Regulatory List Membership (6)
California Proposition 65 (OEHHA) EU Banned in Cosmetics IFRA Fragrance Transparency List FDA Substances Added to Food (EAFUS) Consumer Product Chemical EU CosIng Cosmetics Ingredient Database

Expert Verdict

Expert safety assessment and concern-level summary for STYRENE.

Regulatory Flags

cosing-sourced eu-restricted needs-enrichment endocrine_disruptor prop65 eu_banned_cosmetics ifra_fragrance fda_food_additive eu_cosing_listed

NOAEL Studies Summary

View details ->

Public NOAEL study rows linked to STYRENE by CAS number or substance name.

Studies
16
Lowest NOAEL
21 mg/kg bw/day
Highest NOAEL
1350 mg/kg bw/day
COSMOS_DB

Known Synonyms

Ethenylbenzene Phenylethylene Vinylbenzene Benzene, vinyl- Bulstren K-525-19 EINECS 202-851-5 Ethylene, phenyl- FEMA No. 3233 FEMA Number 3234 NCI-C02200 Stirolo Styreen Vinylbenzen UNII-44LJ2U959V Cinnamenol Cinnaminol Cinnamol Ethenyl-Benzene Ethenylbenzene, 9CI Phenyl-Ethylene

Chemical Function

Fragrance Viscosity modifier Flavouring and nutrient Binder

Regulatory Lists

air; detected; emissions; Europe; Other direct contact consumer goods Arts and crafts/Office supplies - general arts and crafts supplies - arts and crafts paint; detected; Europe drinking_water; Europe; manufacturing; plastic_additive inert_ingredient; non_food_use; Pesticides Arts and crafts/Office supplies - fabric treatment and dye; detected air; Arts and crafts/Office supplies - fabric treatment and dye; Arts and crafts/Office supplies - home office - pens and markers; detected; emissions; Europe Arts and crafts/Office supplies - fabric treatment and dye; detected; Europe air; detected; emissions; Europe; Toys and children's products CEDI OEHHA Proposition 65 (3/2019) detected; Europe; Toys and children's products detected; Europe; Toys and children's products detected; Europe; Toys and children's products detected; Europe; Toys and children's products detected; Europe; Toys and children's products detected; Europe; Toys and children's products air; detected; emissions; Europe; Other direct contact consumer goods air; emissions; Europe; nondetect; Other direct contact consumer goods

Australian Status

AICIS status: listed

Cross-Vertical Safety Context

Same-CAS public records found in pharmaceutical and food safety data.

SOURCE ChEMBL / DrugCentral / FAERS DB_PHARMA CAS match

Pharmaceutical Data

Same-CAS rows from the pharmaceutical spoke database.

Compound
STYRENE
ChEMBL ID
CHEMBL285235
View full pharmaceutical profile →
SOURCE EFSA / FDA GRAS food_additives

Food Safety Data

Same-CAS food additive or FDA GRAS records from the core public database.

Food Name
Styrene
ADI
0.04 mg/kg bw
Food Category
contaminants
View full food safety profile →

Frequently Asked Questions

Is STYRENE safe in cosmetics?

STYRENE has a safety rating of "MODERATE" in our database. EU status: restricted. 10 toxicological study endpoint(s) are available in our database.

Is STYRENE allowed in the EU?

STYRENE EU regulatory status: restricted. Maximum allowed concentration: II/1575. This is based on EU Regulation 1223/2009 and its amendments.

What does STYRENE do in cosmetics?

STYRENE functions as: Solvent. It is classified as a cosmetic ingredient in our database. CAS number: 100-42-5.

What is the NOAEL for STYRENE?

The NOAEL (No Observed Adverse Effect Level) for STYRENE is 21 mg/kg bw/day based on a Carcinogenicity study via oral route in rat. A total of 10 study endpoints are available. Source: COSMOS_DB.

Is STYRENE classified as hazardous under GHS?

STYRENE carries a GHS signal word of "DANGER". Hazard statements: Flammable liquid and vapour Harmful if inhaled Causes skin and eye irritation Suspected of causing cancer Causes damage to the central nervous system and the liver through prolonged or repeated exposure Toxic to aquatic life. 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 used outside cosmetics?

STYRENE also appears in industrial chemical safety, pharmaceutical, and food safety data. The cross-vertical cards on this page render same-CAS public rows from the matched databases.

Does STYRENE have different safety status in cosmetics vs industrial chemicals?

STYRENE is classified GHS Danger (H226, H304, H315, H319, H332, H335, H361, H372) in the chemicals database but is restricted in EU cosmetics at max II/1575.

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