Moderate Cosmetic Ingredient NOAEL Data

Basic Red 51

INCI: BASIC RED 51

CAS Number
77061-58-6
Function
Hair dyeing (semi-permanent/direct cationic dye)
Safety Rating
MODERATE

Regulatory Status

🇪🇺 EU Status prohibited
🇺🇸 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 55 jurisdictions, use the Substance Compliance tool.

Safety Data

Margin of Safety (MoS)
adequate
Dermal Absorption
low
Sensitization
low

Calculate MoS for your specific formulation with the MoS Calculator.

Toxicological Studies

1 study endpoint 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
LOAEL 10 mg/kg bw/day oral rat Subchronic COSMOS_DB

Expert Verdict

Azo dye with potential reductive cleavage to dimethylaminoaniline; additional safety data was required before regulatory approval.

⚠️
Concern Level: Moderate

Regulatory Flags

eu_children_restricted eu_cosing_listed

Frequently Asked Questions

Is Basic Red 51 safe in cosmetics?

Azo dye with potential reductive cleavage to dimethylaminoaniline; additional safety data was required before regulatory approval. The EU classifies Basic Red 51 as "prohibited". Safety rating: MODERATE. 1 toxicological study endpoint(s) are available in our database.

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 Margin of Safety for Basic Red 51?

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 Basic Red 51?

The NOAEL (No Observed Adverse Effect Level) for Basic Red 51 is 10 mg/kg bw/day based on a Subchronic study via oral route in rat. Source: COSMOS_DB.

Compliance Tools

Check Basic Red 51 compliance across multiple jurisdictions:

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Ingredient Decoder
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82 Allergen Checker
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Substance Compliance
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MoS Calculator
Calculate Margin of Safety using SCCS methodology
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Heavy Metal Limits
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