Moderate Cosmetic Ingredient NOAEL Data

2-Tert-Butylhydroquinone Methyl Ether

Also known as: 3-tert-Butyl-4-hydroxyanisole, Phenol, 2-​(1,​1-​dimethylethyl)​-​4-​methoxy-, Phenol, 2-tert-butyl-4-methoxy-, BRN 1867499, Butylated hydroxyanisole I (+13 more)

INCI: 2-TERT-BUTYLHYDROQUINONE METHYL ETHER

2-Tert-Butylhydroquinone Methyl Ether (CAS 121-00-6) is a cosmetic cosmetic ingredient functioning as Fragrance; Fragrance Functional (excipient). NOAEL 50 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 industrial chemical safety data.

View industrial chemical safety profile for CAS 121-00-6 →

Auto-generated CPSR Part A draft with source citations
Function
Fragrance; Fragrance Functional (excipient)
Safety Rating
MODERATE

Chemistry & Identifiers

Formula
C11H16O2
MW
180.24 g/mol
EC Number
204-442-7
PubChem CID
8456
IUPAC Name
2-tert-butyl-4-methoxyphenol
InChIKey
MRBKEAMVRSLQPH-UHFFFAOYSA-N

Regulatory Status

EU EU Status restricted
US US Status permitted
US Notes Not restricted by FDA for cosmetic use; also used as food antioxidant

For full compliance data across multiple jurisdictions, use the Substance Compliance tool.

Safety Data

Margin of Safety, dermal absorption, and sensitization profile summaries for 2-Tert-Butylhydroquinone Methyl Ether.

Calculate MoS for your specific formulation with the MoS Calculator.

Toxicological Studies

5 study endpoints found for 2-Tert-Butylhydroquinone Methyl Ether. 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 =50 mg/kg bw/day oral Rat short-term ToxValDB_ECHA_IUCLID
NOAEL =120 mg/kg bw/day oral Hamster developmental ToxValDB_ECHA_IUCLID
NOAEL =200 mg/kg bw/day oral Rat developmental ToxValDB_ECHA_IUCLID
NOAEL =225 mg/kg bw/day oral Mouse reproduction developmental ToxValDB_ECHA_IUCLID
NOAEL =400 mg/kg bw/day oral Rabbit reproduction developmental ToxValDB_ECHA_IUCLID

Pre-Calculated Safety Assessment

Pre-calculated NOAEL → SED → MoS audit trail for 2-Tert-Butylhydroquinone Methyl Ether across SCCS product categories, with measured dermal absorption where available.

ECHA REACH Registration

European Chemicals Agency REACH dossier and Substances of Very High Concern listing.

Registration Type
Full
Tonnage Band
10 - 100 tonnes
Substance Type
SUBSTANCE
SVHC Candidate
No

PubChem Annotations

Safety and regulatory annotations from PubChem (NCBI) aggregated sources.

Safety (2)
Carcinogen Classification
Butylated hydroxyanisole (BHA) | Group 2B: Possibly carcinogenic to humans | Volume 40: (1986) Some Naturally Occurring and Synthetic Food Components, Furocoumarins and Ultraviolet Radiation | Volume Sup 7: Overall Evaluations of Carcinogenicity: An Updating of IARC Monographs Volumes 1 to 42, 1987; 440 pages; ISBN 92-832-1411-0 (out of print)
Source: International Agency for Research on Cancer (IARC)
Evidence for Carcinogenicity
No data are available in humans. Sufficient evidence of carcinogenicity in animals. OVERALL EVALUATION: Group 2B: The agent is possibly carcinogenic to humans. | Butylated hydroxyanisole (BHA) is reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity from studies in experimental animals.
Source: Hazardous Substances Data Bank (HSDB)
Regulatory (2)
JECFA Evaluation
BHA | 1988 | 0-0.5 mg/kg bw | TRS 776-JECFA 33/14 | FAS 24-JECFA 33/3
Source: Joint FAO/WHO Expert Committee on Food Additives (JECFA)
EU Food Improvement
Food additives
Source: EU Food Improvement Agents

Function Categories & List Membership

Cosmetic/Chemical Function Categories
Fragrance
Regulatory List Membership (2)
IFRA Fragrance Transparency List FDA Indirect Food Contact Additives

Expert Verdict

Expert safety assessment and concern-level summary for 2-Tert-Butylhydroquinone Methyl Ether.

Regulatory Flags

fragrance-component ifra_fragrance

NOAEL Studies Summary

View details ->

Public NOAEL study rows linked to 2-Tert-Butylhydroquinone Methyl Ether by CAS number or substance name.

Studies
5
Lowest NOAEL
50 mg/kg bw/day
Highest NOAEL
400 mg/kg bw/day
ToxValDB_ECHA_IUCLID

Known Synonyms

3-tert-Butyl-4-hydroxyanisole Phenol, 2-​(1,​1-​dimethylethyl)​-​4-​methoxy- Phenol, 2-tert-butyl-4-methoxy- BRN 1867499 Butylated hydroxyanisole I 2-Butyl-4-hydroxyanisole 2-(1,1-Dimethylethyl)-4-methoxy-phenol EINECS 204-442-7 UNII-62RAC24292 2-(1,1-dimethylethyl)-4-methoxyphenol 3-(1,1-dimethylethyl)-4-hydroxyanisole 3-BHA 3-tert-butyl-p-hydroxyanisole 4-hydroxy-3-tert-butylanisole 4-methoxy-2-tert-butylphenol 4-methoxy-6-tert-butylphenol o-tert-butyl-p-methoxyphenol p-methoxy-o-tert-butylphenol

Chemical Function

Fragrance

Regulatory Lists

IFRA Transparency detected; drinking_water; MN Chemical Screening Indirect additives food contact (10/2018) Europe; Food contact items drinking_water; Europe; soil children; Europe Europe; nondetect; Other direct contact consumer goods; Toys and children's products Europe; nondetect; Other direct contact consumer goods; Toys and children's products

Australian Status

AICIS status: listed

Frequently Asked Questions

Is 2-Tert-Butylhydroquinone Methyl Ether safe in cosmetics?

2-Tert-Butylhydroquinone Methyl Ether has a safety rating of "MODERATE" in our database. EU status: restricted. US status: permitted. 5 toxicological study endpoint(s) are available in our database.

Is 2-Tert-Butylhydroquinone Methyl Ether allowed in the EU?

2-Tert-Butylhydroquinone Methyl Ether EU regulatory status: restricted. This is based on EU Regulation 1223/2009 and its amendments.

What does 2-Tert-Butylhydroquinone Methyl Ether do in cosmetics?

2-Tert-Butylhydroquinone Methyl Ether functions as: Fragrance; Fragrance Functional (excipient). It is classified as a cosmetic ingredient in our database. CAS number: 121-00-6.

What is the NOAEL for 2-Tert-Butylhydroquinone Methyl Ether?

The NOAEL (No Observed Adverse Effect Level) for 2-Tert-Butylhydroquinone Methyl Ether is =50 mg/kg bw/day based on a short-term study via oral route in Rat. A total of 5 study endpoints are available. Source: ToxValDB_ECHA_IUCLID.

Is 2-Tert-Butylhydroquinone Methyl Ether used outside cosmetics?

2-Tert-Butylhydroquinone Methyl Ether also appears in industrial chemical safety data. The cross-vertical cards on this page render same-CAS public rows from the matched databases.

Does 2-Tert-Butylhydroquinone Methyl Ether have different safety status in cosmetics vs industrial chemicals?

2-Tert-Butylhydroquinone Methyl Ether is classified GHS CMR hazard (H315, H319, H351, H361, H411, H317, H371, H401) in the chemicals database but is restricted in EU cosmetics.

Is 2-Tert-Butylhydroquinone Methyl Ether in Your Products?

Scan any product label with Piro — our free ingredient scanner. Point your camera at the ingredients list and get instant safety scores for every ingredient.

Try Piro Free →

Analyze Your Full Ingredient List

Paste any INCI list into the Decoder for instant safety analysis, or calculate the Margin of Safety for 2-Tert-Butylhydroquinone Methyl Ether in your formulation.