Is Melatonin safe in cosmetics?
Melatonin has a safety rating of "EXCELLENT" in our database. EU status: permitted. US status: permitted. 10 toxicological study endpoint(s) are available in our database.
Melatonin
Also known as: Regulin, Circadin, 3-(2-Acetamidoethyl)-5-methoxyindole, N-[2-(5-Methoxy-1H-indol-3-yl)ethyl]acetamide, Acetamide, N-[2-(5-methoxy-1H-indol-3-yl)ethyl]- (+15 more)
INCI: MELATONIN
Melatonin (CAS 73-31-4) is a cosmetic active ingredient functioning as Antioxidant; AhR pathway modulator; anti-pollution active; circadian repair. NOAEL 0.5 mg/kg bw/day (cross-referenced against ToxValDB ECHA IUCLID); 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, pharmaceutical, and food safety data.
Function
Antioxidant; AhR pathway modulator; anti-pollution active; circadian repair regulator; anti-inflammatory; indole hormone/neurohormone; night repair active; photoprotective antioxidant
Editorial assessment
EXCELLENT
Preliminary editorial note — not a computed safety verdict.
Chemistry & Identifiers
IUPAC Name
N-[2-(5-methoxy-1H-indol-3-yl)ethyl]acetamide
InChIKey
DRLFMBDRBRZALE-UHFFFAOYSA-N
Regulatory Status
EU EU Status
permitted
US US Status
permitted
US Notes
Permitted in cosmetics; sold as dietary supplement in the US without restriction; topical cosmetic use permitted; no FDA concentration restrictions for cosmetic application; not a CIR-reviewed cosmetic ingredient as of current data
For full compliance data across multiple jurisdictions, use the Substance Compliance tool.
Safety Data
Margin of Safety, dermal absorption, and sensitization profile summaries for Melatonin.
Calculate MoS for your specific formulation with the MoS Calculator.
Toxicological Studies
10 study endpoints found for Melatonin. 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 |
|---|---|---|---|---|---|
| NOAEL | =5 mg/kg bw/day | - | rat | NOAEL study | SCCS Opinion |
| NOAEL | =5 mg/kg bw/day | - | rat | NOAEL study | SCCS Opinion |
| NOAEL | =5 mg/kg bw/day | - | rat | NOAEL study | SCCS Opinion |
| NOAEL | =5 mg/kg bw/day | - | rat | NOAEL study | SCCS Opinion |
| NOAEL | =100 mg/kg bw/day | intravenous | rat | developmental toxicity | SCCS Opinion |
| NOAEL | =100 mg/kg bw/day | intravenous | rat | developmental toxicity | SCCS Opinion |
| NOAEL | =100 mg/kg bw/day | intravenous | rat | developmental toxicity | SCCS Opinion |
| NOAEL | =100 mg/kg bw/day | intravenous | rat | developmental toxicity | SCCS Opinion |
| NOAEL | =200 mg/kg/day | oral | rat | repeated dose toxicity | SCCS Opinion |
| NOAEL | =200 mg/kg bw/day | - | - | reproductive toxicity | SCCS Opinion |
Pre-Calculated Safety Assessment
Conditional — safe only within SCCS limits: hair-care products at 0.0033% w/w, 3 ml scalp application
Pre-calculated NOAEL → SED → MoS audit trail for Melatonin across SCCS product categories, with measured dermal absorption where available.
Dermal Penetration Profile
Skin absorption and penetration characteristics of Melatonin, relevant to systemic exposure and MoS calculations.
Absorption %
10-18%
Penetration Level
epidermis
Penetration Depth
epidermis
Molecular Weight
232.3 Da
Log P
1.2
Systemic Absorption
minimal
Topical Bioavailability
6-14%
Safety Margin Factor
moderate
Vehicle Dependent
Yes — absorption varies by formulation
Source: J Pineal Res 2013
Expanded Dermal Absorption Data
Cross-database dermal penetration: EPA Dryad physics-based, Roberts Mendeley permeation, and SCCS-aggregated measured values.
Aggregated DA Values (1 records across 5 sources)
| Type | DA % | Method | Skin Model | SCCS Ref |
|---|---|---|---|---|
| measured | 100.0% | - | - | SCCS/0022 |
PubChem Annotations
Safety and regulatory annotations from PubChem (NCBI) aggregated sources.
Safety (1)
Carcinogen Classification
No indication of carcinogenicity to humans (not listed by IARC).
Source: Toxin and Toxin Target Database (T3DB)
Function Categories & List Membership
Cosmetic/Chemical Function Categories
Antioxidant
Editorial summary
Preliminary editorial summary for Melatonin — not a computed safety verdict. See the sourced toxicological data above.
Regulatory Flags
anti-pollution
ahr-modulator
ahr-96pct-reduction
circadian-repair
night-cream-active
antioxidant
anti-inflammatory
carnosine-synergy
blue-light-repair
endogenous
NOAEL Studies Summary
View details ->Public NOAEL study rows linked to Melatonin by CAS number or substance name.
Studies
16
Lowest NOAEL
5
Highest NOAEL
200
Units vary across source rows: mg/kg bw/day, mg/kg/day
SCCS Opinion
Dermal Absorption
View details ->| Absorption % | Method | Vehicle |
|---|---|---|
| 100.0% | - | - |
Known Synonyms
Regulin
Circadin
3-(2-Acetamidoethyl)-5-methoxyindole
N-[2-(5-Methoxy-1H-indol-3-yl)ethyl]acetamide
Acetamide, N-[2-(5-methoxy-1H-indol-3-yl)ethyl]-
Acetamide, N-(2-(5-methoxyindol-3-yl)ethyl)-
N-(2-(5-methoxyindol-3-yl)ethyl)acetamide
5-22-12-00042
BRN 0205542
EINECS 200-797-7
UNII-JL5DK93RCL
MT6
Melatonin (synth.) standard-grade
Melatonin (synth.) ultra-pure
N-(2-(5-Methoxy-1H-indol-3-yl)ethyl)acetamide
N-(2-(5-Methoxyindol-3-yl)ethyl)-Acetamide
N-Acetyl-5-methoxy-tryptamine
N-Acetyl-5-methoxy-tryptamine Melatonine
N-[2-(5-Methoxy-1H-indol-3-yl)ethyl)acetamide
N-[2-(5-Methoxy-1H-indol-3-yl)ethyl]-Acetamide
Chemical Function
Antioxidant
Regulatory Lists
Canada; consumer_product; Substances in Products - Canada (4/2014)
active_ingredient; Australia
Canada; Personal care; Substances in PCP - Canada (4/2014)
pharmaceutical
pharmaceutical
active_ingredient; animal_products; Europe; pharmaceutical; residue
Europe; pharmaceutical
Canada; pharmaceutical
Canada; pharmaceutical
Cross-Vertical Safety Context
Same-CAS public records found in pharmaceutical and food safety data.
SOURCE
ChEMBL / DrugCentral / FAERS
DB_PHARMA CAS match
Pharmaceutical Data
Same-CAS rows from the pharmaceutical spoke database.
Compound
MELATONIN
ChEMBL ID
CHEMBL45
Max Phase
4
Adverse Event Associations
4879
SOURCE
EFSA / FDA GRAS
food_additives
Food Safety Data
Same-CAS food additive or FDA GRAS records from the core public database.
Food Name
Melatonin
Food Category
preservative
Frequently Asked Questions
Is Melatonin allowed in the EU?
Melatonin EU regulatory status: permitted. This is based on EU Regulation 1223/2009 and its amendments.
What does Melatonin do in cosmetics?
Melatonin functions as: Antioxidant; AhR pathway modulator; anti-pollution active; circadian repair regulator; anti-inflammatory; indole hormone/neurohormone; night repair active; photoprotective antioxidant. It is classified as a Active Ingredient in our database. CAS number: 73-31-4.
What is the NOAEL for Melatonin?
The NOAEL (No Observed Adverse Effect Level) for Melatonin is =5 mg/kg bw/day based on a NOAEL study study via oral route in rat. A total of 10 study endpoints are available. Source: SCCS Opinion.
Is Melatonin used outside cosmetics?
Melatonin also appears in industrial chemical safety, pharmaceutical, and food safety data. The cross-vertical cards on this page render same-CAS public rows from the matched databases.
Compliance Tools
Check Melatonin compliance across multiple jurisdictions:
Ingredient Decoder
Paste a full ingredient list for instant analysis
82 Allergen Checker
Check for EU declarable fragrance allergens
Substance Compliance
Check compliance across multiple jurisdictions
MoS Calculator
Calculate Margin of Safety using SCCS methodology
Heavy Metal Limits
Compare limits across jurisdictions
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