Ingredient review

CI 40825

INCI: CI 40825

A synthetic yellow dye that adds color to products but offers no skincare benefit; generally considered safe at low concentrations.

beautyskincarecolorant

In plain English

CI 40825 is a man-made yellow colorant used to give cosmetics a bright yellow hue. It doesn't do anything for your skin—it's purely for appearance. In tiny amounts, it's considered safe, but some people prefer to avoid synthetic dyes due to sensitivity concerns.

Review score

Safety, usefulness, and evidence

2.5Fair
2.5/ 5

Higher-caution ingredient

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

Read the cautions before using

CI 40825 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 CI 40825.
  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 azo dye that imparts a yellow color to cosmetic products. It is chemically derived from petroleum and belongs to the same family as many other artificial food and cosmetic colorants.

How it works

It works by absorbing and reflecting specific wavelengths of light, making the product appear yellow. It does not interact with the skin or provide any functional benefit beyond coloring.

Pros

Vibrant color

Delivers a bright, consistent yellow shade that doesn't fade easily in light or over time.

Cost-effective

Synthetic dyes like CI 40825 are inexpensive to produce, keeping product costs lower for consumers.

Cons and cautions

No skincare benefit

This ingredient adds color only; it does not moisturize, protect, or improve skin health.

Potential irritant

While rare, some people may experience mild irritation or allergic reactions, especially with prolonged contact.

Best for

  • Anyone who doesn't mind synthetic colorants in their cosmetics
  • People looking for a stable, bright yellow shade

Use caution if

  • Individuals with sensitive or allergy-prone skin
  • Those seeking only natural or plant-based ingredients

Usage tips

Check the full ingredient list if you have known sensitivities to synthetic dyes.
Patch test a new product containing this colorant on a small area of skin before full use.

Safety summary

CI 40825 is generally recognized as safe for use in cosmetics at low concentrations. However, it offers no skin benefits and may cause irritation in sensitive individuals. Regulatory bodies have set limits to minimize risk.

Research notes

Studies indicate that azo dyes like CI 40825 have low acute toxicity but can cause allergic contact dermatitis in susceptible people. Long-term safety data is limited, but current evidence supports its safe use in rinse-off and leave-on products at approved levels.

Common label clues

Typical concentration
Very low, typically less than 1%
Regulatory status
Approved for use in cosmetics in the US (FDA) and EU (EC) at specified concentration limits. Not permitted in products intended for use around the eyes in some regions.
Common uses
Hair dyes, Soaps, Bath products, Nail polishes
Environmental note
As a synthetic azo dye, it may not biodegrade easily and could contribute to water pollution if not properly treated during manufacturing.

Good to know

  • CI 40825 is also known as Acid Yellow 23 and is sometimes used in food and drugs.
  • It is approved for use in cosmetics in many countries, including the US and EU, at regulated levels.

Common questions

What is CI 40825 in beauty products?

CI 40825 is a man-made yellow colorant used to give cosmetics a bright yellow hue. It doesn't do anything for your skin—it's purely for appearance. In tiny amounts, it's considered safe, but some people prefer to avoid synthetic dyes due to sensitivity concerns.

What does CI 40825 do in a beauty product?

It works by absorbing and reflecting specific wavelengths of light, making the product appear yellow. It does not interact with the skin or provide any functional benefit beyond coloring.

Is CI 40825 safe for most people?

CI 40825 is generally recognized as safe for use in cosmetics at low concentrations. However, it offers no skin benefits and may cause irritation in sensitive individuals. Regulatory bodies have set limits to minimize risk.

Who should be careful with CI 40825?

Individuals with sensitive or allergy-prone skin Those seeking only natural or plant-based ingredients

Research sources

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.