Moderate Fragrance NOAEL Data GHS Classified Sensitization Data Dermal Penetration

Coumarin

INCI: COUMARIN

CAS Number
91-64-5
Function
Fragrance; aroma chemical; sweet/hay/warm note; UV absorber
Safety Rating
MODERATE

Regulatory Status

🇪🇺 EU Status restricted
EU Max Conc. 10 ppm in leave-on products, 100 ppm in rinse-off products
🇺🇸 US Status permitted
US Notes No US federal individual fragrance ingredient disclosure requirement; subject to SCCS cosmetic use limits for brands seeking EU compliance

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

Safety Data

Margin of Safety (MoS)
adequate
Dermal Absorption
high
Sensitization
moderate

Calculate MoS for your specific formulation with the MoS Calculator.

Toxicological Studies

4 study endpoints found for Coumarin. NOAEL (No Observed Adverse Effect Level) values are used to calculate the Margin of Safety per SCCS methodology.

Endpoint Value Route Species Study Type Source
NOEL 42 other other rat inhalation REACH
NOAEL >138.3 mg/kg bw/day oral mouse oral REACH
NOEL 42 mg/kg bw/day dermal rat dermal REACH
NOEL 42 mg/kg bw/day oral rat oral REACH

GHS Hazard Classification

Globally Harmonized System classification per ECHA C&L inventory and ILO/WHO International Chemical Safety Cards.

Short-term Exposure Effects
The substance is irritating to the skin.
Long-term Exposure Effects
This substance is possibly carcinogenic to humans.
Routes of Exposure
The substance can be absorbed into the body by inhalation of its aerosol, through the skin and by ingestion.

Sensitization Profile

Contact sensitization data for Coumarin based on clinical patch test studies and IFRA standards.

Sensitization Rate
low
Allergen Class
fragrance
EU Allergen Listed
yes
Patch Test Positive Rate
0.7%
Cross-reactivity Group
fragrance-mix-II
Reaction Type
contact-dermatitis
IFRA Restricted — max 0.8% in finished products

Source: ESSCA/IVDK

Dermal Penetration Profile

Skin absorption and penetration characteristics of Coumarin, relevant to systemic exposure and MoS calculations.

Absorption %
20-35%
Penetration Level
dermis
Penetration Depth
epidermis/dermis
Molecular Weight
146.1 Da
Log P
1.39
Systemic Absorption
yes
Topical Bioavailability
15-30%
Safety Margin Factor
very-high
Vehicle Dependent
Yes — absorption varies by formulation

Source: SCCS/1459/11, IFRA

Expert Verdict

EU 26 declared allergen with contact allergy sensitization (1.2–6.8% patch-test positivity in fragrance-allergy-suspected patients) and hepatotoxicity concerns from animal studies. IARC concluded not classifiable as a human carcinogen. SCCS has established cosmetic use limits. Must be individually declared on EU labels above threshold. Use within SCCS limits.

⚠️
Concern Level: Moderate

Regulatory Flags

eu-26-allergen label-declaration-required contact-allergen hepatotoxicity-concern sccs-limits iarc-3 eu_children_restricted ifra_fragrance fda_food_additive eu_cosing_listed

Frequently Asked Questions

Is Coumarin safe in cosmetics?

EU 26 declared allergen with contact allergy sensitization (1.2–6.8% patch-test positivity in fragrance-allergy-suspected patients) and hepatotoxicity concerns from animal studies. IARC concluded not classifiable as a human carcinogen. SCCS has established cosmetic use limits. Must be individually declared on EU labels above threshold. Use within SCCS limits. The EU classifies Coumarin as "restricted". Safety rating: MODERATE. 4 toxicological study endpoint(s) are available in our database.

Is Coumarin allowed in the EU?

Coumarin EU regulatory status: restricted. Maximum allowed concentration: 10 ppm in leave-on products, 100 ppm in rinse-off products. This is based on EU Regulation 1223/2009 and its amendments.

What does Coumarin do in cosmetics?

Coumarin functions as: Fragrance; aroma chemical; sweet/hay/warm note; UV absorber. It is classified as a Fragrance in our database. CAS number: 91-64-5.

What is the Margin of Safety for Coumarin?

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.

What is the NOAEL for Coumarin?

The NOAEL (No Observed Adverse Effect Level) for Coumarin is 42 other based on a inhalation study via other route in rat. A total of 4 study endpoints are available. Source: REACH.

Compliance Tools

Check Coumarin compliance across multiple jurisdictions:

🔬
Ingredient Decoder
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82 Allergen Checker
Check for EU declarable fragrance allergens
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Substance Compliance
Check compliance across 55 jurisdictions
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MoS Calculator
Calculate Margin of Safety using SCCS methodology
 ⚗️
Heavy Metal Limits
Compare limits across jurisdictions

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