Also known as: 5-18-02-00516, BRN 0120895, EINECS 207-922-4, 5-Hydroxy-2-(hydroxymethyl)-4-pyrone, UNII-6K23F1TT52 (+2 more)
INCI: KOJIC ACID
Kojic Acid (CAS 501-30-4) is a cosmetic active ingredient functioning as Tyrosinase inhibitor; chelates copper at the enzyme's active site blocking both. NOAEL 2 mg/kg bw/day (PDF-verified against ToxValDB ECHA IUCLID); EU Regulation 1223/2009 status: restricted, max 1%; 5 safety opinions reviewed (SCCS Opinion). Industrial safety data is also available in the chemical safety database.
View industrial chemical safety profile for CAS 501-30-4 →
For full compliance data across multiple jurisdictions, use the Substance Compliance tool.
Margin of Safety, dermal absorption, and sensitization profile summaries for Kojic Acid.
Calculate MoS for your specific formulation with the MoS Calculator.
10 study endpoints found for Kojic Acid. 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 | =100 mg/kg | oral | rat | repeated dose toxicity | CIR Safety Assessment |
| NOAEL | =100 mg/kg | oral | rat | repeated dose toxicity | CIR Safety Assessment |
| NOAEL | =100 mg/kg | oral | rat | repeated dose toxicity | CIR Safety Assessment |
| NOAEL | =100 mg/kg | oral | rat | repeated dose toxicity | CIR Safety Assessment |
| NOAEL | =125 mg/kg | dermal | rat | NOAEL study | CIR Safety Assessment |
| NOAEL | =125 mg/kg | dermal | rat | NOAEL study | CIR Safety Assessment |
| NOAEL | =125 mg/kg | dermal | rat | NOAEL study | CIR Safety Assessment |
| NOAEL | =125 mg/kg | dermal | rat | NOAEL study | CIR Safety Assessment |
| NOAEL | =150 mg/kg | oral | mouse | repeated dose toxicity | CIR Safety Assessment |
| NOAEL | =150 mg/kg | oral | mouse | repeated dose toxicity | CIR Safety Assessment |
Official safety assessments from the Scientific Committee on Consumer Safety (SCCS) and Cosmetic Ingredient Review (CIR).
al endocrine disrupting properties of Kojic acid, the SCCS is of the opinion that Kojic acid is safe when used as a skin lightening agent in cosmetic products at concentrations of up to 1%. 2. Alternatively, what is according to the SCCS the maximum concentration considered safe for use of Ko
al endocrine disrupting properties of Kojic acid, the SCCS is of the opinion that Kojic acid is safe when used as a skin lightening agent in cosmetic products at concentrations of up to 1%. 2. Alternatively, what is according to the SCCS the maximum concentration considered safe for use of Ko
al endocrine disrupting properties of Kojic acid, the SCCS is of the opinion that Kojic acid is safe when used as a skin lightening agent in cosmetic products at concentrations of up to 1%. 2. Alternatively, what is according to the SCCS the maximum concentration considered safe for use of Ko
al endocrine disrupting properties of Kojic acid, the SCCS is of the opinion that Kojic acid is safe when used as a skin lightening agent in cosmetic products at concentrations of up to 1%. 2. Alternatively, what is according to the SCCS the maximum concentration considered safe for use of Ko
al endocrine disrupting properties of Kojic acid, the SCCS is of the opinion that Kojic acid is safe when used as a skin lightening agent in cosmetic products at concentrations of up to 1%. 2. Alternatively, what is according to the SCCS the maximum concentration considered safe for use of Ko
Pre-calculated NOAEL → SED → MoS audit trail for Kojic Acid across SCCS product categories, with measured dermal absorption where available.
NOAEL/LOAEL values cited in official SCCS opinions for Kojic Acid.
| NOAEL | LOAEL | Route | Species | Study | DA% (SCCS) | Opinion |
|---|---|---|---|---|---|---|
| 6 mg/kg/day | 23.8 mg/kg/day | Oral | Rat (male) | Repeated dose (28-day) (28 days (dietary)) | 100 | SCCS/1637/21 (2022) |
| 15.5 mg/kg/day | - | Oral | Rat (male) | Subacute/repeated dose (20-week feeding) (20 weeks (dietary)) | 100 | SCCS/1637/21 (2022) |
| 100 mg/kg/day | - | Dermal | Rat (Wistar) | Repeated dose (28-day) (28 days) | N/A | SCCS/1098/14 (2014) |
| - | - | Oral | Rat/Mouse | Developmental toxicity (Gestational period) | 100 | SCCS/1098/14 (2014) |
Skin absorption and penetration characteristics of Kojic Acid, relevant to systemic exposure and MoS calculations.
Source: J Cosmet Dermatol 2011
International Agency for Research on Cancer (WHO) monograph evaluation.
Cross-referenced EDC classifications, mechanism data, and dose-response evidence from EDLists, SIN List, and cosmetic-specific detail sources.
Source list: II (former)
inhibitor (thyroid peroxidase); weak agonist (ER)
Additional regulatory detail beyond the 7-jurisdiction summary: Saudi SFDA, Korea MFDS, ASEAN ACD, Japan/Korea, Brazil/India, and cross-jurisdictional restriction entries.
| Jurisdiction | Status | Max % | Product Type |
|---|---|---|---|
| CN | banned | - | - |
| AU | restricted | 1.0 | skin lightening |
| GCC | banned | - | Non-compliant skin lightening products |
| BR | banned | - | - |
| UK | restricted | - | - |
Cross-database dermal penetration: EPA Dryad physics-based, Roberts Mendeley permeation, and SCCS-aggregated measured values.
| Type | DA % | Method | Skin Model | SCCS Ref |
|---|---|---|---|---|
| measured | 1.0 | method=measured; type=in_vitro | - | - |
| measured_sccs_opinion | 31.0% | - | - | SCCS/1637/21 |
Reported concentration ranges per product category from SCCS/CIR/industry sources.
| Product Category | Typical Range | Max Reported | Source |
|---|---|---|---|
| Serum | 0.5–2 | 2 | SCCS Opinion |
10 property records from structured ingredient metadata.
Expert safety assessment and concern-level summary for Kojic Acid.
Public NOAEL study rows linked to Kojic Acid by CAS number or substance name.
Units vary across source rows: mg/kg, mg/kg bw/d, mg/kg bw/day
| Absorption % | Method | Vehicle |
|---|---|---|
| 1.0 | method=measured; type=in_vitro | - |
| 31.0% | SCCS opinion extraction | - |
Kojic Acid 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. This ingredient has been reviewed by SCCS Opinion.
Kojic Acid EU regulatory status: restricted. Maximum allowed concentration: 1%. This is based on EU Regulation 1223/2009 and its amendments.
Kojic Acid functions as: Tyrosinase inhibitor; chelates copper at the enzyme's active site blocking both monophenolase and diphenolase activity; clinically used at 1–2.5% for melasma and senile pigmentation. It is classified as a Active Ingredient in our database. CAS number: 501-30-4.
The NOAEL (No Observed Adverse Effect Level) for Kojic Acid is =100 mg/kg based on a repeated dose toxicity study via oral route in rat. A total of 10 study endpoints are available. Source: CIR Safety Assessment.
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