INCI: METHYLIMIDAZOLIUMPROPYL P-PHENYLENEDIAMINE HCL (DESIGNATION A166)
Methylimidazoliumpropyl p-Phenylenediamine HCl (CAS 220158-86-1) is a cosmetic cosmetic ingredient functioning as Hair Dyeing - oxidative hair dye precursor. Reported NOAEL =0.0183 mg/kg in rat (SCCS Opinion); EU Regulation 1223/2009 status: restricted, max 2%. Industrial safety data is also available in the chemical safety database.
View industrial chemical safety profile for CAS 220158-86-1 →
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Margin of Safety, dermal absorption, and sensitization profile summaries for Methylimidazoliumpropyl p-Phenylenediamine HCl.
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10 study endpoints found for Methylimidazoliumpropyl p-Phenylenediamine HCl. 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 | =0.0183 mg/kg | oral | rat | developmental toxicity | SCCS Opinion |
| NOAEL | =0.0183 mg/kg | oral | rat | developmental toxicity | SCCS Opinion |
| NOAEL | =0.0183 mg/kg | oral | rat | developmental toxicity | SCCS Opinion |
| NOAEL | =0.0183 mg/kg | oral | rat | developmental toxicity | SCCS Opinion |
| NOAEL | =100 mg/kg/day | - | - | developmental toxicity | SCCS Opinion |
| NOAEL | =100 mg/kg bw/d | - | rat | developmental toxicity | SCCS Opinion |
| NOAEL | =100 mg/kg/day | - | - | developmental toxicity | SCCS Opinion |
| NOAEL | =100 mg/kg bw/d | - | rat | developmental toxicity | SCCS Opinion |
| NOAEL | =100 mg/kg/day | - | - | developmental toxicity | SCCS Opinion |
| NOAEL | =100 mg/kg bw/d | - | rat | developmental toxicity | SCCS Opinion |
Additional regulatory detail beyond the 7-jurisdiction summary: Saudi SFDA, Korea MFDS, ASEAN ACD, Japan/Korea, Brazil/India, and cross-jurisdictional restriction entries.
Cross-database dermal penetration: EPA Dryad physics-based, Roberts Mendeley permeation, and SCCS-aggregated measured values.
| Type | DA % | Method | Skin Model | SCCS Ref |
|---|---|---|---|---|
| measured | 2.0% | in_vitro | - | SCCS/0231 |
| measured | 0.07% | - | - | SCCS/0231 |
| measured | 97.59% | - | - | SCCS/0231 |
| measured | 99.35% | - | - | SCCS/0231 |
| measured | 1.12% | - | - | SCCS/0231 |
Expert safety assessment and concern-level summary for Methylimidazoliumpropyl p-Phenylenediamine HCl.
Public NOAEL study rows linked to Methylimidazoliumpropyl p-Phenylenediamine HCl by CAS number or substance name.
Units vary across source rows: mg/kg, mg/kg/day, mg/kg bw/d
| Absorption % | Method | Vehicle |
|---|---|---|
| 2.0% | in_vitro | - |
| 0.07% | - | - |
| 97.59% | - | - |
| 99.35% | - | - |
| 1.12% | - | - |
Methylimidazoliumpropyl p-Phenylenediamine HCl 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.
Methylimidazoliumpropyl p-Phenylenediamine HCl EU regulatory status: restricted. Maximum allowed concentration: 2%. This is based on EU Regulation 1223/2009 and its amendments.
Methylimidazoliumpropyl p-Phenylenediamine HCl functions as: Hair Dyeing - oxidative hair dye precursor. It is classified as a cosmetic ingredient in our database. CAS number: 220158-86-1.
The NOAEL (No Observed Adverse Effect Level) for Methylimidazoliumpropyl p-Phenylenediamine HCl is =0.0183 mg/kg based on a developmental toxicity study via oral route in rat. A total of 10 study endpoints are available. Source: SCCS Opinion.
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