Is 4-Nitro-O-Phenylenediamine safe in cosmetics?
4-Nitro-O-Phenylenediamine 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.
4-Nitro-O-Phenylenediamine
Also known as: 4-13-00-00075, BRN 0608106, EINECS 202-766-3, NCI-C03941, 4-Nitro-para-phenylenediamine (+7 more)
INCI: 4-NITRO-O-PHENYLENEDIAMINE
4-Nitro-O-Phenylenediamine (CAS 99-56-9) is a cosmetic cosmetic ingredient functioning as Hair colorant used in both oxidative (permanent) and direct (semi-permanent). NOAEL 340 mg/kg bw/day (cross-referenced against ToxValDB ECHA IUCLID); EU Regulation 1223/2009 status: restricted. Industrial safety data is also available in the chemical safety database. Same-CAS public records also appear in pharmaceutical data.
View industrial chemical safety profile for CAS 99-56-9 →
Auto-generated CPSR Part A draft with source citations
Function
Hair colorant used in both oxidative (permanent) and direct (semi-permanent) dye formulations
Safety Rating
MODERATE
Regulatory Status
EU EU Status
restricted
US US Status
permitted
US Notes
Coal-tar hair dye exemption; CIR Panel concluded safe as oxidative hair dye at current use levels
For full compliance data across multiple jurisdictions, use the Substance Compliance tool.
Safety Data
Margin of Safety, dermal absorption, and sensitization profile summaries for 4-Nitro-O-Phenylenediamine.
Calculate MoS for your specific formulation with the MoS Calculator.
Toxicological Studies
10 study endpoints found for 4-Nitro-O-Phenylenediamine. 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 | =15 mg/kg bw/d | dermal | rat | NOAEL study | CIR_vision_codex |
| NOAEL | =15 mg/kg bw/d | dermal | rat | NOAEL study | CIR_vision_codex |
| NOAEL | =15 mg/kg bw/d | dermal | rat | NOAEL study | CIR_vision_codex |
| NOAEL | =15 mg/kg bw/d | dermal | rat | NOAEL study | CIR_vision_codex |
| NOAEL | =45 mg/kg bw/d | dermal | rat | NOAEL study | CIR_vision_codex |
| NOAEL | =45 mg/kg bw/d | dermal | rat | NOAEL study | CIR_vision_codex |
| NOAEL | =45 mg/kg bw/d | dermal | rat | NOAEL study | CIR_vision_codex |
| NOAEL | =45 mg/kg bw/d | dermal | rat | NOAEL study | CIR_vision_codex |
| NOAEL | =0.042 mg/kg | oral | rat | dermal absorption | SCCS_vision_codex |
| NOAEL | =0.042 mg/kg | oral | rat | dermal absorption | SCCS_vision_codex |
GHS Hazard Classification
Globally Harmonized System classification per ECHA C&L inventory and ILO/WHO International Chemical Safety Cards.
Long-term Exposure Effects
Repeated or prolonged contact may cause skin sensitization.
Pre-Calculated Safety Assessment
Pre-calculated NOAEL → SED → MoS audit trail for 4-Nitro-O-Phenylenediamine across SCCS product categories, with measured dermal absorption where available.
Sensitization Profile
Contact sensitization data for 4-Nitro-O-Phenylenediamine 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: IVDK; NACDG; ESSCA
IARC Carcinogenicity
International Agency for Research on Cancer (WHO) monograph evaluation.
IARC Group
3
Volume
16, Sup 7
Evaluation Year
1987
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 1.5%. 기타 제품에는 사용금지
SA Saudi SFDA (III - Restricted)
Product type: Hair dye substance in oxidative hair dye products.
BRIN Brazil/India Cosmetics
India: Restricted
Additional Jurisdictional Restrictions (1)
| Jurisdiction | Status | Max % | Product Type |
|---|---|---|---|
| IN | restricted | 1.0 | oxidative hair dye only |
Expanded Dermal Absorption Data
Cross-database dermal penetration: EPA Dryad physics-based, Roberts Mendeley permeation, and SCCS-aggregated measured values.
EPA Dryad Skin Absorption (physics-based)
MW: 153.141
LogP: 0.880102
Kp epidermis: 0.00746 cm/h
% dose epidermis: 0.98%
% dose stratum corneum: 0.97%
% dose dermis: 0.95%
Source: EPA_Dryad_Skin_Absorption_2024
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": "IVDK; NACDG; ESSCA"}
hair_dye
{"cas_number": "99-56-9", "ingredient_class": "oxidative_dye_coupler", "chemical_class": "other", "molecular_weight_Da": "153.14", "color_result_on_hair": "Orange-yellow modifier", "shade_range": "red", "primary_function": "coupler", "oxidative_dye_type": "coupler", "requires_developer": "yes", "permanence": "permanent", "oxidation_mechanism": "coupling", "hair_penetration_depth": "cortex", "sensi…
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 4-Nitro-O-Phenylenediamine.
Regulatory Flags
colorant
eu_cosing_listed
NOAEL Studies Summary
View details ->Public NOAEL study rows linked to 4-Nitro-O-Phenylenediamine by CAS number or substance name.
Studies
32
Lowest NOAEL
0.042
Highest NOAEL
265
Units vary across source rows: mg/kg bw/d, mg/kg/day, mg/kg bw/day
CIR_vision_codex
SCCS_vision_codex
Known Synonyms
4-13-00-00075
BRN 0608106
EINECS 202-766-3
NCI-C03941
4-Nitro-para-phenylenediamine
4-Nitrophenylenediamine
4-Nitro-o-phenylene-diamine
4-Nitro-1,2-fenylendiamin
Nitro-o-phenylenediamine
UNII-5A9AX7Y0TT
p-nitro-o-phenylendiamine
p-nitro-o-phenylenediamine
Chemical Function
Dye
Regulatory Lists
Europe; Personal care; restricted
Australian Status
AICIS status: listed
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
CHEMBL433721
Frequently Asked Questions
Is 4-Nitro-O-Phenylenediamine allowed in the EU?
4-Nitro-O-Phenylenediamine EU regulatory status: restricted. This is based on EU Regulation 1223/2009 and its amendments.
What does 4-Nitro-O-Phenylenediamine do in cosmetics?
4-Nitro-O-Phenylenediamine functions as: Hair colorant used in both oxidative (permanent) and direct (semi-permanent) dye formulations. It is classified as a cosmetic ingredient in our database. CAS number: 99-56-9.
What is the NOAEL for 4-Nitro-O-Phenylenediamine?
The NOAEL (No Observed Adverse Effect Level) for 4-Nitro-O-Phenylenediamine is =15 mg/kg bw/d based on a NOAEL study study via dermal route in rat. A total of 10 study endpoints are available. Source: CIR_vision_codex.
Is 4-Nitro-O-Phenylenediamine used outside cosmetics?
4-Nitro-O-Phenylenediamine also appears in pharmaceutical data. The cross-vertical cards on this page render same-CAS public rows from the matched databases.
Compliance Tools
Check 4-Nitro-O-Phenylenediamine 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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