Poor Cosmetic Ingredient NOAEL Data GHS Classified Sensitization Data

O-Aminophenol

INCI: O-AMINOPHENOL

CAS Number
95-55-6
Function
Hair dye (oxidative)
Safety Rating
POOR

Regulatory Status

🇪🇺 EU Status restricted
EU Max Conc. 2.0%
🇺🇸 US Status permitted
US Notes Permitted under coal-tar hair dye exemption (FD&C Act §601(a)); requires caution statement and patch-test directive on label

For full compliance data across 55 jurisdictions, use the Substance Compliance tool.

Safety Data

Margin of Safety (MoS)
adequate
Dermal Absorption
moderate
Sensitization
high

Calculate MoS for your specific formulation with the MoS Calculator.

Toxicological Studies

2 study endpoints found for O-Aminophenol. 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
LOAEL 2 mg/kg bw/day oral rat Short Term Toxicity COSMOS_DB
NOAEL 5 mg/kg bw/day oral rat oral REACH

GHS Hazard Classification

Globally Harmonized System classification per ECHA C&L inventory and ILO/WHO International Chemical Safety Cards.

Short-term Exposure Effects
The substance may cause effects on the blood. This may result in the formation of methaemoglobin. The effects may be delayed. Medical observation is indicated.
Long-term Exposure Effects
Repeated or prolonged contact may cause skin sensitization.
Routes of Exposure
The substance can be absorbed into the body by ingestion, through the skin and by inhalation of its aerosol.

Sensitization Profile

Contact sensitization data for O-Aminophenol based on clinical patch test studies and IFRA standards.

Sensitization Rate
low
Allergen Class
dye
EU Allergen Listed
no
Patch Test Positive Rate
0.3%
Cross-reactivity Group
para-amino-group
Reaction Type
contact-dermatitis

Source: IVDK; NACDG; ESSCA

Expert Verdict

Restricted to oxidative hair dye only; must not be used in eyebrow or eyelash products; mandatory label warnings including Contains o-Aminophenol and Can cause allergic reaction; SCCS re-evaluation pending for updated sensitization and mutagenicity data

⚠️
Concern Level: High

Regulatory Flags

potential-allergen endocrine_disruptor

Frequently Asked Questions

Is O-Aminophenol safe in cosmetics?

Restricted to oxidative hair dye only; must not be used in eyebrow or eyelash products; mandatory label warnings including Contains o-Aminophenol and Can cause allergic reaction; SCCS re-evaluation pending for updated sensitization and mutagenicity data The EU classifies O-Aminophenol as "restricted". Safety rating: POOR. 2 toxicological study endpoint(s) are available in our database.

Is O-Aminophenol allowed in the EU?

O-Aminophenol EU regulatory status: restricted. Maximum allowed concentration: 2.0%. This is based on EU Regulation 1223/2009 and its amendments.

What does O-Aminophenol do in cosmetics?

O-Aminophenol functions as: Hair dye (oxidative). It is classified as a cosmetic ingredient in our database. CAS number: 95-55-6.

What is the Margin of Safety for O-Aminophenol?

adequate The Margin of Safety (MoS) is calculated using SCCS methodology. A MoS above 100 is generally considered safe. Use the MoS Calculator tool to calculate MoS for your specific formulation and product category.

What is the NOAEL for O-Aminophenol?

The NOAEL (No Observed Adverse Effect Level) for O-Aminophenol is 2 mg/kg bw/day based on a Short Term Toxicity study via oral route in rat. A total of 2 study endpoints are available. Source: COSMOS_DB.

Compliance Tools

Check O-Aminophenol compliance across multiple jurisdictions:

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Ingredient Decoder
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82 Allergen Checker
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Substance Compliance
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MoS Calculator
Calculate Margin of Safety using SCCS methodology
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Heavy Metal Limits
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