Is Basic Red 51 safe in cosmetics?
Basic Red 51 has a safety rating of "MODERATE" in our database. EU status: prohibited. US status: permitted. 10 toxicological study endpoint(s) are available in our database.
Basic Red 51
Also known as: 1H-Imidazolium, 2-[2-[4-(dimethylamino)phenyl]diazenyl]-1,3-dimethyl-, chloride (1:1)
INCI: BASIC RED 51
Basic Red 51 (CAS 77061-58-6) is a cosmetic cosmetic ingredient functioning as Hair dyeing (semi-permanent/direct cationic dye). NOAEL 20 mg/kg bw/day (cross-referenced against ToxValDB ECHA IUCLID); EU Regulation 1223/2009 status: prohibited. Industrial safety data is also available in the chemical safety database. Same-CAS public records also appear in industrial chemical safety data.
View industrial chemical safety profile for CAS 77061-58-6 →
Auto-generated CPSR Part A draft with source citations
Cross-Vertical Regulatory Divergence
Basic Red 51 is prohibited in EU cosmetics but has active industrial GHS classifications (H302, H315, H319, H400, H410).
Source: Cosmetics: ingredients.eu_status; Chemicals: ghs_classifications.signal_word/hazard_statement_code
Function
Hair dyeing (semi-permanent/direct cationic dye)
Safety Rating
MODERATE
Regulatory Status
EU EU Status
prohibited
US US Status
permitted
US Notes
Not an FDA-approved color additive; coal tar hair dye exemption applies when used in hair dyes with required caution labeling
For full compliance data across multiple jurisdictions, use the Substance Compliance tool.
Safety Data
Margin of Safety, dermal absorption, and sensitization profile summaries for Basic Red 51.
Calculate MoS for your specific formulation with the MoS Calculator.
Toxicological Studies
10 study endpoints found for Basic Red 51. 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 | =10 mg/kg/day | dermal | - | repeated dose toxicity | SCCNFP_vision_codex |
| NOAEL | =10 mg/kg bw/day | oral | - | repeated dose toxicity | SCCNFP_vision_codex |
| NOAEL | =10 mg/kg/day | dermal | - | repeated dose toxicity | SCCNFP_vision_codex |
| NOAEL | =10 mg/kg bw/day | oral | - | repeated dose toxicity | SCCNFP_vision_codex |
| NOAEL | =10 mg/kg/day | dermal | - | repeated dose toxicity | SCCNFP_vision_codex |
| NOAEL | =10 mg/kg bw/day | oral | - | repeated dose toxicity | SCCNFP_vision_codex |
| NOAEL | =10 mg/kg/day | dermal | - | repeated dose toxicity | SCCNFP_vision_codex |
| NOAEL | =10 mg/kg bw/day | oral | - | repeated dose toxicity | SCCNFP_vision_codex |
| NOAEL | =12.25 mg/kg | dermal | rat | repeated dose toxicity | SCCNFP_vision_codex |
| NOAEL | =12.25 mg/kg bw/day | oral | - | repeated dose toxicity | SCCNFP_vision_codex |
Pre-Calculated Safety Assessment
Pre-calculated NOAEL → SED → MoS audit trail for Basic Red 51 across SCCS product categories, with measured dermal absorption where available.
ECHA REACH Registration
European Chemicals Agency REACH dossier and Substances of Very High Concern listing.
Registration Type
Full
Tonnage Band
1 - 10 tonnes
Substance Type
SUBSTANCE
SVHC Candidate
No
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.
KR Korea MFDS Annex 2 (Restricted)
Category: Restricted. Max: 산화염모제에 0.5%. 그 외 사용기준은 「화장품의 색소종류와 기준 및 시험방법」에 따름
SA Saudi SFDA (III - Restricted)
Product type: (a) Hair dye substance in oxidative hair dye products (b) Hair dye substance in non-oxidatie hair dye products. Max: (b) 1,0 %.
BRIN Brazil/India Cosmetics
India: Restricted · max (b) 1,0 %
Additional Jurisdictional Restrictions (1)
| Jurisdiction | Status | Max % | Product Type |
|---|---|---|---|
| BR | banned | - | - |
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_sccs_opinion | 0.13% | - | - | SCCS/1332/10 |
| measured_sccs_opinion | 0.13% | - | - | SCCS/1436/11 |
Additional Ingredient Properties
1 property record from structured ingredient metadata.
hair_dye
{"cas_number": "77061-58-6", "ingredient_class": "direct_dye", "chemical_class": "other", "color_result_on_hair": "Red-violet", "shade_range": "red", "primary_function": "direct_deposit", "requires_developer": "no", "deposit_only": "yes", "permanence": "semi_permanent", "wash_fastness_shampoos": "8-15", "light_fastness": "moderate", "oxidation_mechanism": "direct_absorption", "hair_penetration_dep…
Function Categories & List Membership
Cosmetic/Chemical Function Categories
Dye
Regulatory List Membership (2)
EU Restricted for Children (Cosmetics)
EU CosIng Cosmetics Ingredient Database
Expert Verdict
Expert safety assessment and concern-level summary for Basic Red 51.
Regulatory Flags
eu_children_restricted
eu_cosing_listed
NOAEL Studies Summary
View details ->Public NOAEL study rows linked to Basic Red 51 by CAS number or substance name.
Studies
64
Lowest NOAEL
0.005
Highest NOAEL
2000
Units vary across source rows: mg/kg, mg/kg bw/day, mg/kg bw
SCCS_vision_codex
SCCNFP_vision_codex
Dermal Absorption
View details ->| Absorption % | Method | Vehicle |
|---|---|---|
| 0.13% | SCCS PDF direct extraction | - |
| 0.13% | SCCS PDF direct extraction | - |
Known Synonyms
1H-Imidazolium, 2-[2-[4-(dimethylamino)phenyl]diazenyl]-1,3-dimethyl-, chloride (1:1)
Chemical Function
Dye
Regulatory Lists
children; Europe; Personal care
Europe; Personal care - hair coloring
Europe; Personal care - hair coloring
Europe; Personal care - hair coloring
Europe; Personal care - hair coloring
Europe; Personal care; restricted
Australian Status
AICIS status: listed
Frequently Asked Questions
Is Basic Red 51 allowed in the EU?
Basic Red 51 EU regulatory status: prohibited. This is based on EU Regulation 1223/2009 and its amendments.
What does Basic Red 51 do in cosmetics?
Basic Red 51 functions as: Hair dyeing (semi-permanent/direct cationic dye). It is classified as a cosmetic ingredient in our database. CAS number: 77061-58-6.
What is the NOAEL for Basic Red 51?
The NOAEL (No Observed Adverse Effect Level) for Basic Red 51 is =10 mg/kg/day based on a repeated dose toxicity study via dermal route in rat. A total of 10 study endpoints are available. Source: SCCNFP_vision_codex.
Is Basic Red 51 used outside cosmetics?
Basic Red 51 also appears in industrial chemical safety data. The cross-vertical cards on this page render same-CAS public rows from the matched databases.
Does Basic Red 51 have different safety status in cosmetics vs industrial chemicals?
Basic Red 51 is prohibited in EU cosmetics but has active industrial GHS classifications (H302, H315, H319, H400, H410).
Compliance Tools
Check Basic Red 51 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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