Is Basic Brown 4 safe in cosmetics?
Basic Brown 4 has a safety rating of "POOR" in our database. EU status: prohibited. US status: permitted.
POOR
Cosmetic Ingredient
Basic Brown 4
Also known as: 1,3-Benzenediamine, 4,4'-[(4-methyl-1,3-phenylene)bis(azo)]bis[6-methyl-, dihydrochloride, 1,3-Benzenediamine, 4,4'-[(4-methyl-1,3-phenylene)bis(2,1-diazenediyl)]bis[6-methyl-, hydrochloride (1:2), C.I. Basic Brown 4, Astra Vesuvine B, Basic Brown 2K (+3 more)
INCI: BASIC BROWN 4
Basic Brown 4 (CAS 5421-66-9) is a cosmetic cosmetic ingredient functioning as Hair colorant (bis-azo dye). EU Regulation 1223/2009 status: prohibited. Industrial safety data is also available in the chemical safety database.
Function
Hair colorant (bis-azo dye)
Editorial assessment
POOR
Preliminary editorial note — not a computed safety verdict.
Regulatory Status
EU EU Status
prohibited
US US Status
permitted
US Notes
Not an FDA-approved color additive; coal tar hair dye exemption may apply
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 Brown 4.
Calculate MoS for your specific formulation with the MoS Calculator.
Editorial summary
Preliminary editorial summary for Basic Brown 4 — not a computed safety verdict. See the sourced toxicological data above.
Regulatory Flags
colorant
Known Synonyms
1,3-Benzenediamine, 4,4'-[(4-methyl-1,3-phenylene)bis(azo)]bis[6-methyl-, dihydrochloride
1,3-Benzenediamine, 4,4'-[(4-methyl-1,3-phenylene)bis(2,1-diazenediyl)]bis[6-methyl-, hydrochloride (1:2)
C.I. Basic Brown 4
Astra Vesuvine B
Basic Brown 2K
Bismark Brown R
EINECS 226-541-4
NSC 7812
Australian Status
AICIS status: listed
Frequently Asked Questions
Is Basic Brown 4 allowed in the EU?
Basic Brown 4 EU regulatory status: prohibited. This is based on EU Regulation 1223/2009 and its amendments.
What does Basic Brown 4 do in cosmetics?
Basic Brown 4 functions as: Hair colorant (bis-azo dye). It is classified as a cosmetic ingredient in our database. CAS number: 5421-66-9.
Compliance Tools
Check Basic Brown 4 compliance across multiple jurisdictions:
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
Heavy Metal Limits
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