Also known as: Ethanol, 2-[[2-(2-hydroxyethoxy)-4-nitrophenyl]amino]-, 2-[[2-(2-Hydroxyethoxy)-4-nitrophenyl]amino]ethanol, 2-[3-Nitro-6-(β-hydroxyethylamino)phenoxy]ethanol, Colorex HCY 4, PHENOL, N,O-DI(HYDROXYETHYL)-2-AMINO-5-NITRO- (+5 more)
INCI: HC YELLOW NO. 4
HC Yellow No. 4 (CAS 59820-43-8) is a cosmetic cosmetic ingredient functioning as Hair Dyeing (non-oxidative semi-permanent). NOAEL 240 mg/kg bw/day (cross-referenced against ToxValDB ECHA IUCLID); EU Regulation 1223/2009 status: restricted, max 1.5%; 1 safety opinion reviewed (cir). Industrial safety data is also available in the chemical safety database. Same-CAS public records also appear in industrial chemical safety and pharmaceutical data.
US NotesPermitted under coal-tar hair dye exemption (FD&C Act §601(a))
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Safety Data
Margin of Safety, dermal absorption, and sensitization profile summaries for HC Yellow No. 4.
Calculate MoS for your specific formulation with the
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Toxicological Studies
10 study endpoints found for HC Yellow No. 4. 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
=0.001 mg/kg bw
oral
rat
dermal absorption
SCCS_vision_codex
NOAEL
=0.001 mg/kg bw
oral
rat
dermal absorption
SCCS_vision_codex
NOAEL
=0.001 mg/kg bw
oral
rat
dermal absorption
SCCS_vision_codex
NOAEL
=0.001 mg/kg bw
oral
rat
dermal absorption
SCCS_vision_codex
NOAEL
=50 mg/kg/d
oral
rat
developmental toxicity
SCCS_vision_codex
NOAEL
=50 mg/kg bw/d
dermal
rat
developmental toxicity
SCCS_vision_codex
NOAEL
=50 mg/kg bw
oral
rat
dermal absorption
SCCS_vision_codex
NOAEL
=50 mg/kg/d
oral
rat
developmental toxicity
SCCS_vision_codex
NOAEL
=50 mg/kg bw/d
dermal
rat
developmental toxicity
SCCS_vision_codex
NOAEL
=50 mg/kg bw
oral
rat
dermal absorption
SCCS_vision_codex
Safety Opinions
Official safety assessments from the Scientific Committee on Consumer Safety (SCCS) and Cosmetic Ingredient Review (CIR).
cir
Verdict: safe
nimal and clinical data presented in this report, the Expert Panel concluded that HC Yellow No. 4 is safe as a hair colorant in the present practices of use. REFERENCES Adams, R. M., H. I. Maibach, W. E. Clendenning, et al. 1985. A five-year study of cosmetic reactions. J. Am. Acad. Dermatol. 13:1062-106
Pre-Calculated Safety Assessment
Pre-calculated NOAEL → SED → MoS audit trail for HC Yellow No. 4 across SCCS product categories, with measured dermal absorption where available.
Sensitization Profile
Contact sensitization data for HC Yellow No. 4 based on clinical patch test studies and IFRA standards.
Sensitization Rate
low
Allergen Class
dye
EU Allergen Listed
no
Patch Test Positive Rate
0.1%
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
57
Evaluation Year
1992
ECHA REACH Registration
European Chemicals Agency REACH dossier and Substances of Very High Concern listing.
Registration Type
Full
Tonnage Band
No longer valid
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.
Safety and regulatory annotations from PubChem (NCBI) aggregated sources.
Safety (2)
Carcinogen Classification
HC Yellow No. 4 | Group 3: Not classifiable as to its carcinogenicity to humans | Volume 57: (1993) Occupational Exposures of Hairdressers and Barbers and Personal Use of Hair Colourants; Some Hair Dyes, Cosmetic Colourants, Industrial Dyestuffs and Aromatic Amines
Source: International Agency for Research on Cancer (IARC)
Carcinogen Classification
HC Yellow 4 | TR-419: Toxicology and Carcinogenesis Studies of HC Yellow 4 (CASRN 59820-43-8) in F344 Rats and B6C3F1 Mice (Feed Studies) (1992 ) | 07/09/91 | Equivocal Evidence | No Evidence | No Evidence | No Evidence | Under the conditions of these 2-year feed studies, there was equivocal evidence of carcinogenic activity of HC Yellow 4 in male F344/N rats based on the increased incide
Source: NTP Technical Reports
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 HC Yellow No. 4.
HC Yellow No. 4 has a safety rating of "GOOD" in our database. EU status: restricted. US status: permitted. 10 toxicological study endpoint(s) are available in our database. This ingredient has been reviewed by cir.
Is HC Yellow No. 4 allowed in the EU?
HC Yellow No. 4 EU regulatory status: restricted. Maximum allowed concentration: 1.5%. This is based on EU Regulation 1223/2009 and its amendments.
What does HC Yellow No. 4 do in cosmetics?
HC Yellow No. 4 functions as: Hair Dyeing (non-oxidative semi-permanent). It is classified as a cosmetic ingredient in our database. CAS number: 59820-43-8.
What is the NOAEL for HC Yellow No. 4?
The NOAEL (No Observed Adverse Effect Level) for HC Yellow No. 4 is =0.001 mg/kg bw based on a dermal absorption study via oral route in rat. A total of 10 study endpoints are available. Source: SCCS_vision_codex.
Is HC Yellow No. 4 used outside cosmetics?
HC Yellow No. 4 also appears in industrial chemical safety and pharmaceutical data. The cross-vertical cards on this page render same-CAS public rows from the matched databases.
Compliance Tools
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