Is Rhododendrol safe in cosmetics?
Rhododendrol has a safety rating of "POOR" in our database. EU status: permitted. US status: permitted.
Poor
Cosmetic Ingredient
Rhododendrol
Also known as: UNII-97PTR2F3Z8, (-)-Betuligenol, (R)-(-)-Rhododendrol, (R)-Frambinol, 2-Butanol, 4-(p-hydroxyphenyl)- (+4 more)
INCI: RHODODENDROL (ALSO KNOWN AS RHODODENOL / 4-(4-HYDROXYPHENYL)-2-BUTANOL / 4HPB)
Rhododendrol (CAS 501-96-2) is a cosmetic cosmetic ingredient functioning as Skin lightening/depigmentation — tyrosinase inhibitor; originally developed and. EU Regulation 1223/2009 status: permitted. 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 501-96-2 →
Auto-generated CPSR Part A draft with source citations
Function
Skin lightening/depigmentation — tyrosinase inhibitor; originally developed and patented by Kanebo as a quasi-drug active in Japan
Safety Rating
POOR
Chemistry & Identifiers
IUPAC Name
4-[(3R)-3-hydroxybutyl]phenol
InChIKey
SFUCGABQOMYVJW-MRVPVSSYSA-N
Regulatory Status
EU EU Status
permitted
US US Status
permitted
US Notes
Not approved as an OTC drug active; could technically be used as a cosmetic ingredient, but post-recall stigma and liability risk make it commercially non-viable
For full compliance data across multiple jurisdictions, use the Substance Compliance tool.
Safety Data
Margin of Safety, dermal absorption, and sensitization profile summaries for Rhododendrol.
Calculate MoS for your specific formulation with the MoS Calculator.
Function Categories & List Membership
Cosmetic/Chemical Function Categories
Softener and conditioner
Expert Verdict
Expert safety assessment and concern-level summary for Rhododendrol.
Known Synonyms
UNII-97PTR2F3Z8
(-)-Betuligenol
(R)-(-)-Rhododendrol
(R)-Frambinol
2-Butanol, 4-(p-hydroxyphenyl)-
Benzenepropanol, 4-hydroxy-alpha-methyl-, (alphaR)-
Benzenepropanol, 4-hydroxy-alpha-methyl-, (R)-
Betuligenol
Betuligenol, (-)-
Chemical Function
Softener and conditioner
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
CHEMBL1086681
Frequently Asked Questions
Is Rhododendrol allowed in the EU?
Rhododendrol EU regulatory status: permitted. This is based on EU Regulation 1223/2009 and its amendments.
What does Rhododendrol do in cosmetics?
Rhododendrol functions as: Skin lightening/depigmentation — tyrosinase inhibitor; originally developed and patented by Kanebo as a quasi-drug active in Japan. It is classified as a cosmetic ingredient in our database. CAS number: 501-96-2.
Is Rhododendrol used outside cosmetics?
Rhododendrol 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.
Compliance Tools
Check Rhododendrol compliance across multiple jurisdictions:
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Substance Compliance
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MoS Calculator
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Heavy Metal Limits
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