Ingredient review

Mercaptoisopropyl-5-Methylcyclohexanone

INCI: MERCAPTOISOPROPYL-5-METHYLCYCLOHEXANONE

A synthetic fragrance ingredient with limited safety data; best for those who tolerate fragrance well.

beautyskincarefragrance

In plain English

This is a man-made chemical used to add a specific smell to skincare and beauty products. It belongs to a group of ingredients called mercaptans, which are known for their strong odors. Because it is a fragrance ingredient, it doesn't provide any skin benefit like moisturizing or anti-aging—it's purely for scent. People with sensitive skin or fragrance allergies may want to avoid it.

Review score

Safety, usefulness, and evidence

3.0Fair
3.0/ 5

Useful in the right context, but not low-maintenance

The evidence base is still emerging, so marketing claims deserve extra caution.

Main practical flags: irritation is moderate; clogging risk is low.

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

Quick decision guide

Read the cautions before using

Mercaptoisopropyl-5-Methylcyclohexanone can be useful, but watch for some irritation potential.

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 Mercaptoisopropyl-5-Methylcyclohexanone.
  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

moderate

Can bother some users, especially with frequent use, damaged skin, or strong companion ingredients.

Clogging risk

low

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

Evidence level

emerging

The ingredient may be promising, but claims should be treated more cautiously.

What it is

A synthetic organic compound from the mercaptan family, used as a fragrance ingredient in cosmetics.

How it works

It evaporates from the skin's surface, releasing molecules that interact with olfactory receptors in the nose to create a perception of scent. It does not actively interact with skin cells or provide any functional skincare benefit.

Pros

Enhances product appeal

Adds a pleasant scent that can make the application experience more enjoyable.

Low comedogenic risk

Unlikely to clog pores, making it suitable for acne-prone skin if tolerated.

Cons and cautions

Potential irritant

Can cause redness, itching, or stinging in people with sensitive skin or fragrance allergies.

Limited safety research

There is little publicly available data on long-term skin exposure, so its safety profile is not fully established.

Best for

  • People who enjoy scented products and have no history of fragrance allergies
  • Those looking for a specific scent note in their routine

Use caution if

  • Individuals with sensitive skin or known fragrance allergies
  • Anyone following a fragrance-free skincare routine

Usage tips

Patch test any product containing this ingredient on a small area of skin before full use.
If you have sensitive skin, opt for fragrance-free versions of your favorite products.

Safety summary

Considered safe for most people at low concentrations used in cosmetics, but may cause irritation or allergic reactions in sensitive individuals. Limited independent safety data is available.

Research notes

There is minimal peer-reviewed research specifically on this compound in cosmetic use. Safety assessments rely on general fragrance ingredient guidelines.

Common label clues

Typical concentration
Very low, typically less than 1%
Regulatory status
Approved for use in cosmetics in the EU and US, but subject to general fragrance safety regulations. No specific restrictions found for this compound.
Common uses
Fragranced products, Perfumes, Body lotions
Environmental note
As a synthetic compound, its environmental persistence and biodegradability are not well documented. General fragrance ingredients can contribute to water pollution.

Good to know

  • This ingredient is not a preservative, humectant, or active skincare ingredient—it is purely for scent.
  • Fragrance ingredients are often listed simply as 'fragrance' or 'parfum' on labels, so this specific name may not always appear.

Common questions

What is Mercaptoisopropyl-5-Methylcyclohexanone in beauty products?

This is a man-made chemical used to add a specific smell to skincare and beauty products. It belongs to a group of ingredients called mercaptans, which are known for their strong odors. Because it is a fragrance ingredient, it doesn't provide any skin benefit like moisturizing or anti-aging—it's purely for scent. People with sensitive skin or fragrance allergies may want to avoid it.

What does Mercaptoisopropyl-5-Methylcyclohexanone do in a beauty product?

It evaporates from the skin's surface, releasing molecules that interact with olfactory receptors in the nose to create a perception of scent. It does not actively interact with skin cells or provide any functional skincare benefit.

Is Mercaptoisopropyl-5-Methylcyclohexanone safe for most people?

Considered safe for most people at low concentrations used in cosmetics, but may cause irritation or allergic reactions in sensitive individuals. Limited independent safety data is available.

Who should be careful with Mercaptoisopropyl-5-Methylcyclohexanone?

Individuals with sensitive skin or known fragrance allergies Anyone following a fragrance-free skincare routine

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.