Is 6-Hydroxyindole safe in cosmetics?
6-Hydroxyindole has a safety rating of "GOOD" in our database. EU status: restricted. US status: permitted.
6-Hydroxyindole
INCI: 6-HYDROXYINDOLE
6-Hydroxyindole (CAS 2380-86-1 (per CIR/SCCP records)) is a cosmetic cosmetic ingredient functioning as Hair colorant (oxidative hair dye). EU Regulation 1223/2009 status: restricted, max 0.5%. Industrial safety data is also available in the chemical safety database.
View industrial chemical safety profile for CAS 2380-86-1 (per CIR/SCCP records) →
Auto-generated CPSR Part A draft with source citations
Function
Hair colorant (oxidative hair dye)
Safety Rating
GOOD
Regulatory Status
EU EU Status
restricted
EU Max Conc.
0.5%
US US Status
permitted
US Notes
CIR Expert Panel concluded safe for use in oxidative hair dye formulations
For full compliance data across multiple jurisdictions, use the Substance Compliance tool.
Safety Data
Margin of Safety, dermal absorption, and sensitization profile summaries for 6-Hydroxyindole.
Calculate MoS for your specific formulation with the MoS Calculator.
Sensitization Profile
Contact sensitization data for 6-Hydroxyindole based on clinical patch test studies and IFRA standards.
Sensitization Rate
low
Allergen Class
dye
EU Allergen Listed
no
Patch Test Positive Rate
0.2%
Cross-reactivity Group
para-amino-group
Reaction Type
contact-dermatitis
Source: SCCS; IVDK
Additional Ingredient Properties
2 property records from structured ingredient metadata.
allergen_detail
{"eu_allergen_listed": "no", "allergen_class": "dye", "cross_reactivity_group": "para-amino-group", "patch_test_frequency_pct": "0.2", "sensitization_rate": "low", "common_reaction_type": "contact-dermatitis", "ifra_restricted": "no", "source": "SCCS; IVDK"}
hair_dye
{"cas_number": "2380-86-1", "ingredient_class": "oxidative_dye_coupler", "chemical_class": "other", "molecular_weight_Da": "133.15", "color_result_on_hair": "Blue modifier", "shade_range": "brown", "primary_function": "coupler", "oxidative_dye_type": "coupler", "requires_developer": "yes", "permanence": "permanent", "oxidation_mechanism": "coupling", "hair_penetration_depth": "cortex", "sensitizat…
Expert Verdict
Expert safety assessment and concern-level summary for 6-Hydroxyindole.
Regulatory Flags
colorant
eu_cosing_listed
NOAEL Studies Summary
View details ->Public NOAEL study rows linked to 6-Hydroxyindole by CAS number or substance name.
Studies
16
Lowest NOAEL
0 mg/kg bw/day
Highest NOAEL
100 mg/kg bw/day
SCCNFP_vision_codex
Frequently Asked Questions
Is 6-Hydroxyindole allowed in the EU?
6-Hydroxyindole EU regulatory status: restricted. Maximum allowed concentration: 0.5%. This is based on EU Regulation 1223/2009 and its amendments.
What does 6-Hydroxyindole do in cosmetics?
6-Hydroxyindole functions as: Hair colorant (oxidative hair dye). It is classified as a cosmetic ingredient in our database. CAS number: 2380-86-1 (per CIR/SCCP records).
Compliance Tools
Check 6-Hydroxyindole compliance across multiple jurisdictions:
Ingredient Decoder
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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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