Rhododendrol
INCI: RHODODENDROL (ALSO KNOWN AS RHODODENOL / 4-(4-HYDROXYPHENYL)-2-BUTANOL / 4HPB)
Regulatory Status
For full compliance data across 55 jurisdictions, use the Substance Compliance tool.
Safety Data
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Expert Verdict
🚨 CRITICAL: Caused widespread chemical leukoderma (vitiligo-like depigmentation) in ~19,000+ consumers in Japan (2013); Kanebo recalled 54 products across Asia . Mechanism: rhododendrol is metabolized by tyrosinase into cytotoxic quinone metabolites that kill melanocytes. Do NOT formulate with this ingredient. Despite passing pre-market safety testing, post-market surveillance revealed serious irreversible harm .
Frequently Asked Questions
Is Rhododendrol safe in cosmetics?
🚨 CRITICAL: Caused widespread chemical leukoderma (vitiligo-like depigmentation) in ~19,000+ consumers in Japan (2013); Kanebo recalled 54 products across Asia . Mechanism: rhododendrol is metabolized by tyrosinase into cytotoxic quinone metabolites that kill melanocytes. Do NOT formulate with this ingredient. Despite passing pre-market safety testing, post-market surveillance revealed serious irreversible harm . The EU classifies Rhododendrol as "permitted". Safety rating: POOR.
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.
What is the Margin of Safety for Rhododendrol?
adequate The Margin of Safety (MoS) is calculated using SCCS methodology. A MoS above 100 is generally considered safe. Use the MoS Calculator tool to calculate MoS for your specific formulation and product category.
Compliance Tools
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Related Ingredients
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