Ingredient review

Acid Blue 74

INCI: CI 73015

A safe, widely used synthetic blue dye that adds color but offers no skincare benefits.

beautyskincarecolorant

In plain English

CI 73015, also known as Acid Blue 74 or Indigo Carmine, is a synthetic blue dye. It is used in cosmetics to give products a blue or violet color. It does not treat skin conditions or provide any active skincare benefits—it is purely for aesthetic purposes. Regulatory bodies like the FDA and EU CosIng have approved it for use in cosmetics at safe levels.

Review score

Safety, usefulness, and evidence

3.5Good
3.5/ 5

Potentially useful with some tradeoffs

The evidence base is useful, but some claims depend heavily on the formula.

Risk flags are low for most users, though the finished product can still irritate.

Source
synthetic
Evidence
moderate
Irritation
low
Clogging risk
low
How reviews are scored

Quick decision guide

Useful, but context matters

Acid Blue 74 is generally a lower-concern ingredient when the full formula suits your skin.

Plain-English read

Treat this as a practical screening step before you compare products that contain this ingredient.

  1. Step 1Start with the score, then check the irritation and clogging risk before judging Acid Blue 74.
  2. Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
  3. Step 3If a product stings, breaks you out, or worsens irritation, judge the finished formula and stop using it even if the ingredient scores well.

Score terms in plain English

Irritation risk

low

Less likely to sting, burn, or bother most users, though sensitive skin can still react.

Clogging risk

low

Less likely to feel heavy or contribute to clogged pores for most skin types.

Evidence level

moderate

There is useful support, but formula details and claim strength still matter.

What it is

A synthetic organic compound derived from indigo, used as a colorant in cosmetics and personal care products.

How it works

It absorbs and reflects light in the blue-violet spectrum, imparting color to the product. It is water-soluble and stable under normal cosmetic formulation conditions.

Pros

Vibrant color

Provides a bright, consistent blue shade that is stable in water-based formulas.

Regulatory approval

Approved by the FDA and EU for use in cosmetics, with a long history of safe use.

Cons and cautions

No skincare benefits

It is purely a colorant and does not moisturize, protect, or treat the skin.

Potential staining

Can stain fabrics, skin, or nails temporarily, especially in high concentrations.

Best for

  • Anyone wanting a blue-tinted cosmetic product
  • Formulators needing a water-soluble blue dye

Use caution if

  • Individuals with known sensitivity to synthetic dyes
  • Those seeking skincare benefits from colorants

Usage tips

Use in water-based products for best color dispersion.
Avoid high concentrations to minimize staining risk.
Patch test if you have sensitive skin or known dye allergies.

Safety summary

CI 73015 is considered safe for use in cosmetics at regulated concentrations. Rare allergic reactions or irritation may occur in sensitive individuals. It is not a skin treatment ingredient.

Research notes

Studies confirm low acute toxicity and low skin irritation potential. The Cosmetic Ingredient Review (CIR) panel has reviewed similar colorants and found them safe for cosmetic use.

Common label clues

Typical concentration
Up to 1% in leave-on products, up to 3% in rinse-off products
Regulatory status
Approved as a color additive in cosmetics by the FDA (21 CFR 74.2305) and EU CosIng (CI 73015).
Common uses
Eyeshadows, Eyeliners, Lip products, Soaps, Bath products
Environmental note
Synthetic dyes may persist in water systems; proper disposal is recommended to minimize environmental impact.

Good to know

  • CI 73015 is the same as FD&C Blue No. 2, commonly used in food and drugs.
  • It is not a natural ingredient; it is synthesized from petroleum or coal tar sources.

Common questions

What is Acid Blue 74 in beauty products?

CI 73015, also known as Acid Blue 74 or Indigo Carmine, is a synthetic blue dye. It is used in cosmetics to give products a blue or violet color. It does not treat skin conditions or provide any active skincare benefits—it is purely for aesthetic purposes. Regulatory bodies like the FDA and EU CosIng have approved it for use in cosmetics at safe levels.

What does Acid Blue 74 do in a beauty product?

It absorbs and reflects light in the blue-violet spectrum, imparting color to the product. It is water-soluble and stable under normal cosmetic formulation conditions.

Is Acid Blue 74 safe for most people?

CI 73015 is considered safe for use in cosmetics at regulated concentrations. Rare allergic reactions or irritation may occur in sensitive individuals. It is not a skin treatment ingredient.

Who should be careful with Acid Blue 74?

Individuals with known sensitivity to synthetic dyes Those seeking skincare benefits from colorants

Research sources

FDA Color Additive Status ListOpenEU CosIng DatabaseOpenCIR Safety Assessment of ColorantsOpen

Ingredient reviews are educational and are not medical advice. Patch test new products and ask a licensed clinician about persistent irritation, allergies, pregnancy-specific questions, or diagnosed skin conditions.