Is 2-Methyl-1-Naphthol safe in cosmetics?
2-Methyl-1-Naphthol has a safety rating of "MODERATE" in our database. EU status: restricted. US status: permitted. 10 toxicological study endpoint(s) are available in our database.
2-Methyl-1-Naphthol
Also known as: EINECS 231-265-2, 2-Methyl-alpha-naphthol, NSC 402211, UNII-COU5JQ433I
2-Methyl-1-Naphthol (CAS 7469-77-4) is a cosmetic cosmetic ingredient functioning as Dye. Reported NOAEL =0.07 mg/kg bw in rat (SCCS_vision_codex); EU Regulation 1223/2009 status: restricted, max 2.0%. Industrial safety data is also available in the chemical safety database. Same-CAS public records also appear in industrial chemical safety and pharmaceutical data.
View industrial chemical safety profile for CAS 7469-77-4 →
Auto-generated CPSR Part A draft with source citations
Cross-Vertical Regulatory Divergence
2-Methyl-1-Naphthol is classified GHS Danger (H315, H318, H335) in the chemicals database but is restricted in EU cosmetics at max 2.0%.
Source: Cosmetics: ingredients.eu_status/eu_max; Chemicals: ghs_classifications.signal_word/hazard_statement_code
Chemistry & Identifiers
IUPAC Name
2-methylnaphthalen-1-ol
InChIKey
SRJCJJKWVSSELL-UHFFFAOYSA-N
Regulatory Status
EU EU Status
restricted
EU Max Conc.
2.0%
US US Status
permitted
US Notes
FD&C Act §601 hair dye exemption applies; requires patch-test warning
For full compliance data across multiple jurisdictions, use the Substance Compliance tool.
Safety Data
Margin of Safety, dermal absorption, and sensitization profile summaries for 2-Methyl-1-Naphthol.
Calculate MoS for your specific formulation with the MoS Calculator.
Toxicological Studies
10 study endpoints found for 2-Methyl-1-Naphthol. 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 | =0.07 mg/kg bw | oral | rat | dermal absorption | SCCS_vision_codex |
| NOAEL | =0.07 mg/kg bw | oral | rat | dermal absorption | SCCS_vision_codex |
| NOAEL | =0.07 mg/kg bw | oral | rat | dermal absorption | SCCS_vision_codex |
| NOAEL | =0.07 mg/kg bw | oral | rat | dermal absorption | SCCS_vision_codex |
| NOAEL | =75 mg/kg bw/day | oral | - | developmental toxicity | SCCS_vision_codex |
| NOAEL | =75 mg/kg bw | oral | rat | dermal absorption | SCCS_vision_codex |
| NOAEL | =75 mg/kg bw/day | oral | - | developmental toxicity | SCCS_vision_codex |
| NOAEL | =75 mg/kg bw | oral | rat | dermal absorption | SCCS_vision_codex |
| NOAEL | =75 mg/kg bw/day | oral | - | developmental toxicity | SCCS_vision_codex |
| NOAEL | =75 mg/kg bw | oral | rat | dermal absorption | SCCS_vision_codex |
Expanded Jurisdictional Detail
Additional regulatory detail beyond the 7-jurisdiction summary: Saudi SFDA, Korea MFDS, ASEAN ACD, Japan/Korea, Brazil/India, and cross-jurisdictional restriction entries.
SA Saudi SFDA (III - Restricted)
Product type: Hair dye substance in oxidative hair dye products.
BRIN Brazil/India Cosmetics
India: Restricted
Expanded Dermal Absorption Data
Cross-database dermal penetration: EPA Dryad physics-based, Roberts Mendeley permeation, and SCCS-aggregated measured values.
Aggregated DA Values (2 records across 5 sources)
| Type | DA % | Method | Skin Model | SCCS Ref |
|---|---|---|---|---|
| measured | 1.42% | - | - | SCCP/0154 |
| measured | 2.0% | - | - | SCCP/0154 |
Additional Ingredient Properties
1 property record from structured ingredient metadata.
hair_dye
{"cas_number": "7469-77-4", "ingredient_class": "oxidative_dye_coupler", "chemical_class": "naphtol", "molecular_weight_Da": "158.20", "color_result_on_hair": "Red-violet", "shade_range": "red", "primary_function": "coupler", "oxidative_dye_type": "coupler", "requires_developer": "yes", "permanence": "permanent", "oxidation_mechanism": "coupling", "coupling_position": "meta", "hair_penetration_dep…
Function Categories & List Membership
Cosmetic/Chemical Function Categories
Dye
Regulatory List Membership (1)
EU CosIng Cosmetics Ingredient Database
Expert Verdict
Expert safety assessment and concern-level summary for 2-Methyl-1-Naphthol.
Regulatory Flags
eu_cosing_listed
NOAEL Studies Summary
View details ->Public NOAEL study rows linked to 2-Methyl-1-Naphthol by CAS number or substance name.
Studies
24
Lowest NOAEL
0.07
Highest NOAEL
500
Units vary across source rows: mg/kg bw/day, mg/kg bw
SCCS_vision_codex
Dermal Absorption
View details ->| Absorption % | Method | Vehicle |
|---|---|---|
| 1.42% | - | - |
| 2.0% | - | - |
Known Synonyms
EINECS 231-265-2
2-Methyl-alpha-naphthol
NSC 402211
UNII-COU5JQ433I
Chemical Function
Dye
Regulatory Lists
Europe; Personal care; restricted
Cross-Vertical Safety Context
Same-CAS public records found in pharmaceutical data.
SOURCE
ChEMBL / DrugCentral / FAERS
DB_PHARMA CAS match
Pharmaceutical Data
Same-CAS rows from the pharmaceutical spoke database.
ChEMBL ID
CHEMBL122451
Frequently Asked Questions
Is 2-Methyl-1-Naphthol allowed in the EU?
2-Methyl-1-Naphthol EU regulatory status: restricted. Maximum allowed concentration: 2.0%. This is based on EU Regulation 1223/2009 and its amendments.
What does 2-Methyl-1-Naphthol do in cosmetics?
2-Methyl-1-Naphthol functions as: Dye. It is classified as a cosmetic ingredient in our database. CAS number: 7469-77-4.
What is the NOAEL for 2-Methyl-1-Naphthol?
The NOAEL (No Observed Adverse Effect Level) for 2-Methyl-1-Naphthol is =0.07 mg/kg bw based on a dermal absorption study via oral route in rat. A total of 10 study endpoints are available. Source: SCCS_vision_codex.
Is 2-Methyl-1-Naphthol used outside cosmetics?
2-Methyl-1-Naphthol also appears in industrial chemical safety and pharmaceutical data. The cross-vertical cards on this page render same-CAS public rows from the matched databases.
Does 2-Methyl-1-Naphthol have different safety status in cosmetics vs industrial chemicals?
2-Methyl-1-Naphthol is classified GHS Danger (H315, H318, H335) in the chemicals database but is restricted in EU cosmetics at max 2.0%.
Compliance Tools
Check 2-Methyl-1-Naphthol compliance across multiple jurisdictions:
Ingredient Decoder
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82 Allergen Checker
Check for EU declarable fragrance allergens
Substance Compliance
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MoS Calculator
Calculate Margin of Safety using SCCS methodology
Heavy Metal Limits
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