Poor Cosmetic Ingredient

CI 41000 (Auramine O / Basic Yellow 2)

INCI: CI 41000

CAS Number

2465-27-2

Function

Colorant. Synthetic diarylmethane yellow dye (Auramine O, also known as Basic Yellow 2, C.I. Basic Yellow 2). Produces bright yellow coloration. Primarily an industrial, histological, and laboratory staining dye rather than a cosmetic colorant. Used in textile dyeing, paper, leather, and fluorescence microscopy.

Safety Rating

POOR

Regulatory Status

🇪🇺 EU Status prohibited

🇺🇸 US Status prohibited

US Notes CI 41000 (Auramine O / Basic Yellow 2) is not listed on the FDA Color Additives Permitted for Use in Cosmetics (21 CFR Parts 73, 74, or 82). It has no established FDA color additive listing for cosmetic use. Use in US cosmetics is not authorized. Auramine O is recognized by IARC and NTP as a probable human carcinogen (Group 2A) based on occupational exposure studies.

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

Safety Data

Margin of Safety (MoS)

not established

Dermal Absorption

high

Sensitization

high

Calculate MoS for your specific formulation with the MoS Calculator.

Expert Verdict

CI 41000 (Auramine O / Basic Yellow 2) is a synthetic diarylmethane dye classified as a probable human carcinogen by IARC (Group 2A) and is prohibited in EU cosmetics and not authorized for US cosmetic use due to carcinogenic risk and absence from all cosmetic colorant positive lists.

⚠️

Concern Level: High

Regulatory Flags

not-in-eu-annex-iv eu-prohibited-by-omission not-fda-listed no-cosmetic-authorization iarc-group-2a-probable-carcinogen ntp-carcinogen industrial-dye-only cationic-dye dna-binding occupational-hazard

Frequently Asked Questions

Is CI 41000 (Auramine O / Basic Yellow 2) safe in cosmetics?

Is CI 41000 (Auramine O / Basic Yellow 2) allowed in the EU?

CI 41000 (Auramine O / Basic Yellow 2) EU regulatory status: prohibited. This is based on EU Regulation 1223/2009 and its amendments.

What does CI 41000 (Auramine O / Basic Yellow 2) do in cosmetics?

CI 41000 (Auramine O / Basic Yellow 2) functions as: Colorant. Synthetic diarylmethane yellow dye (Auramine O, also known as Basic Yellow 2, C.I. Basic Yellow 2). Produces bright yellow coloration. Primarily an industrial, histological, and laboratory staining dye rather than a cosmetic colorant. Used in textile dyeing, paper, leather, and fluorescence microscopy.. It is classified as a cosmetic ingredient in our database. CAS number: 2465-27-2.

What is the Margin of Safety for CI 41000 (Auramine O / Basic Yellow 2)?

not established 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.

Compliance Tools

Check CI 41000 (Auramine O / Basic Yellow 2) compliance across multiple jurisdictions:

🔬

Ingredient Decoder

Paste a full ingredient list for instant analysis

🌸

82 Allergen Checker

Check for EU declarable fragrance allergens

🧪

Substance Compliance

Check compliance across 55 jurisdictions

🧮

MoS Calculator

Calculate Margin of Safety using SCCS methodology

⚗️

Heavy Metal Limits

Compare limits across jurisdictions

Related Ingredients

CI 77007 (Ultramarine Blue)

Excellent

CI 77019 (Mica)

Excellent

CI 76518

Moderate

CI 45350

Good

CI 14700 (FD&C Red No. 4 / Red 4)

Good

Browse all 30,000+ ingredients →

📱

Is CI 41000 (Auramine O / Basic Yellow 2) 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 CI 41000 (Auramine O / Basic Yellow 2) in your formulation.

Ingredient Decoder MoS Calculator