Is 4-T-Butyl Styrene safe in cosmetics?
4-T-Butyl Styrene has a safety rating of "POOR" in our database. EU status: prohibited. US status: permitted.
Poor
Cosmetic Ingredient
4-T-Butyl Styrene
Also known as: 1-tert-Butyl-4-ethenylbenzene, p-tert-Butylstyrene, 1-tert-Butyl-4-vinylbenzene, Benzene, 1-(1,1-dimethylethyl)-4-ethenyl-, 1-(1,1-Dimethylethyl)-4-ethenylbenzene (+6 more)
INCI: 4-T-BUTYL STYRENE
4-T-Butyl Styrene (CAS 1746-23-2) is a cosmetic cosmetic ingredient functioning as Masking / fragrance (limited cosmetic use). 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 1746-23-2 →
Auto-generated CPSR Part A draft with source citations
Cross-Vertical Regulatory Divergence
4-T-Butyl Styrene is prohibited in EU cosmetics but has active industrial GHS classifications (H304, H315, H319, H335, H361f, H400, H410).
Source: Cosmetics: ingredients.eu_status; Chemicals: ghs_classifications.signal_word/hazard_statement_code
Function
Masking / fragrance (limited cosmetic use)
Safety Rating
POOR
Regulatory Status
EU EU Status
prohibited
US US Status
permitted
US Notes
Limited cosmetic use; no specific FDA restriction found but extremely limited data
For full compliance data across multiple jurisdictions, use the Substance Compliance tool.
Safety Data
Margin of Safety, dermal absorption, and sensitization profile summaries for 4-T-Butyl Styrene.
Calculate MoS for your specific formulation with the MoS Calculator.
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
SVHC Candidate
No
Function Categories & List Membership
Cosmetic/Chemical Function Categories
No specific technical function
Expert Verdict
Expert safety assessment and concern-level summary for 4-T-Butyl Styrene.
Regulatory Flags
fragrance-component
Known Synonyms
1-tert-Butyl-4-ethenylbenzene
p-tert-Butylstyrene
1-tert-Butyl-4-vinylbenzene
Benzene, 1-(1,1-dimethylethyl)-4-ethenyl-
1-(1,1-Dimethylethyl)-4-ethenylbenzene
Styrene, p-tert-butyl-
p-t-Butylstyrene
4-t-Butylstyrene
1-Ethenyl-4-tert-butylbenzene
4-tert-Butyl-1-ethenylbenzene
EINECS 217-126-9
Chemical Function
No specific technical function
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
CHEMBL3183165
Frequently Asked Questions
Is 4-T-Butyl Styrene allowed in the EU?
4-T-Butyl Styrene EU regulatory status: prohibited. This is based on EU Regulation 1223/2009 and its amendments.
What does 4-T-Butyl Styrene do in cosmetics?
4-T-Butyl Styrene functions as: Masking / fragrance (limited cosmetic use). It is classified as a cosmetic ingredient in our database. CAS number: 1746-23-2.
Is 4-T-Butyl Styrene used outside cosmetics?
4-T-Butyl Styrene 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 4-T-Butyl Styrene have different safety status in cosmetics vs industrial chemicals?
4-T-Butyl Styrene is prohibited in EU cosmetics but has active industrial GHS classifications (H304, H315, H319, H335, H361f, H400, H410).
Compliance Tools
Check 4-T-Butyl Styrene 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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