Thorium Dioxide
INCI: THORIUM DIOXIDE — NO COSMETIC INCI (RADIOACTIVE SUBSTANCE)
Regulatory Status
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Safety Data
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Expert Verdict
IARC Group 1 carcinogen; radioactive (alpha emitter, t½ ~14 billion years); causes hepatic angiosarcoma and leukemia. Absolutely prohibited
Regulatory Flags
Frequently Asked Questions
Is Thorium Dioxide safe in cosmetics?
IARC Group 1 carcinogen; radioactive (alpha emitter, t½ ~14 billion years); causes hepatic angiosarcoma and leukemia. Absolutely prohibited The EU classifies Thorium Dioxide as "prohibited". Safety rating: POOR.
Is Thorium Dioxide allowed in the EU?
Thorium Dioxide EU regulatory status: prohibited. This is based on EU Regulation 1223/2009 and its amendments.
What does Thorium Dioxide do in cosmetics?
Thorium Dioxide functions as: Historically used as X-ray contrast agent (Thorotrast); no legitimate cosmetic function. It is classified as a cosmetic ingredient in our database. CAS number: 1314-20-1.
What is the Margin of Safety for Thorium Dioxide?
not established 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
Check Thorium Dioxide compliance across multiple jurisdictions:
Related Ingredients
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