Poor Cosmetic Ingredient

Terephthalaldehyde

INCI: TEREPHTHALALDEHYDE

CAS Number
623-27-8
Function
Not a typical cosmetic active — this is a dialdehyde (benzene-1,4-dicarbaldehyde), potentially used as a cross-linker or fixative
Safety Rating
POOR

Regulatory Status

🇪🇺 EU Status restricted
🇺🇸 US Status permitted
US Notes Not specifically addressed for cosmetic use

For full compliance data across 55 jurisdictions, use the Substance Compliance tool.

Safety Data

Margin of Safety (MoS)
not established
Dermal Absorption
moderate
Sensitization
high

Calculate MoS for your specific formulation with the MoS Calculator.

Expert Verdict

🔴 STRONG CONCERN — dialdehyde = potent cross-linker of proteins; expected strong skin sensitizer; potential mutagenicity concern (aldehyde-DNA adducts); irritant to eyes and respiratory system. Highly unlikely to be appropriate for leave-on cosmetics. Verify any intended use very carefully.

⚠️
Concern Level: High

Regulatory Flags

potential-allergen

Frequently Asked Questions

Is Terephthalaldehyde safe in cosmetics?

🔴 STRONG CONCERN — dialdehyde = potent cross-linker of proteins; expected strong skin sensitizer; potential mutagenicity concern (aldehyde-DNA adducts); irritant to eyes and respiratory system. Highly unlikely to be appropriate for leave-on cosmetics. Verify any intended use very carefully. The EU classifies Terephthalaldehyde as "restricted". Safety rating: POOR.

Is Terephthalaldehyde allowed in the EU?

Terephthalaldehyde EU regulatory status: restricted. This is based on EU Regulation 1223/2009 and its amendments.

What does Terephthalaldehyde do in cosmetics?

Terephthalaldehyde functions as: Not a typical cosmetic active — this is a dialdehyde (benzene-1,4-dicarbaldehyde), potentially used as a cross-linker or fixative. It is classified as a cosmetic ingredient in our database. CAS number: 623-27-8.

What is the Margin of Safety for Terephthalaldehyde?

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 Terephthalaldehyde compliance across multiple jurisdictions:

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Ingredient Decoder
Paste a full ingredient list for instant analysis
 🌸
82 Allergen Checker
Check for EU declarable fragrance allergens
 🧪
Substance Compliance
Check compliance across 55 jurisdictions
 🧮
MoS Calculator
Calculate Margin of Safety using SCCS methodology
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Heavy Metal Limits
Compare limits across jurisdictions

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