Ingredient review

Hexahydro-Tetramethyl-Methanoazulen-5-Yl Methyl Ketone

INCI: HEXAHYDRO-TETRAMETHYL-METHANOAZULEN-5-YL METHYL KETONE

A synthetic fragrance ingredient that adds a warm, woody scent but offers no skincare benefits and may cause irritation in sensitive individuals.

beautyskincarefragrance

In plain English

This is a man-made chemical used to give skincare and beauty products a pleasant woody or amber-like smell. It doesn't moisturize, treat, or improve your skin—it's purely for fragrance. While generally considered safe at low levels, it can sometimes cause irritation or allergic reactions, especially if you have sensitive skin.

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

Hexahydro-Tetramethyl-Methanoazulen-5-Yl Methyl Ketone 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 Hexahydro-Tetramethyl-Methanoazulen-5-Yl Methyl Ketone.
  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 from the azulene family, created in a lab to mimic natural woody or amber scents. It is not derived from plants or animals.

How it works

It evaporates from the skin's surface, releasing aromatic molecules that your nose perceives as a warm, woody scent. It has no active effect on skin structure or function.

Pros

Pleasant scent profile

Adds a warm, woody, amber-like aroma that many find appealing and long-lasting on the skin.

Low irritation for most

At typical low concentrations, it rarely causes problems for people without fragrance sensitivities.

Cons and cautions

No skincare benefit

It only provides fragrance—no moisturizing, anti-aging, or protective effects for your skin.

Potential allergen

Like many synthetic fragrances, it can trigger contact dermatitis or allergic reactions in sensitive individuals.

Best for

  • People who enjoy woody or amber fragrances in their products
  • Those without fragrance sensitivities looking for a pleasant scent

Use caution if

  • Individuals with sensitive, reactive, or eczema-prone skin
  • Anyone with a known fragrance allergy

Usage tips

Patch test any product containing this ingredient on a small area of skin before full use.
If you have sensitive skin, choose fragrance-free alternatives to avoid potential irritation.

Safety summary

Generally recognized as safe for most people at low concentrations used in cosmetics. However, it can cause skin irritation or allergic reactions in sensitive individuals. The Cosmetic Ingredient Review (CIR) has not specifically evaluated this compound, but similar synthetic fragrances are considered safe with restrictions.

Research notes

Limited peer-reviewed studies specifically on this ingredient. Evidence is based on general knowledge of synthetic fragrance compounds, which are widely used and monitored for allergenicity. The EU Scientific Committee on Consumer Safety (SCCS) evaluates similar fragrance ingredients.

Common label clues

Typical concentration
Typically less than 1% in leave-on products
Regulatory status
Approved for use in cosmetics in the EU, US, and many other regions, subject to concentration limits and labeling requirements for allergens.
Common uses
Perfumes, Body lotions, Facial moisturizers, Hair products
Environmental note
As a synthetic compound, its environmental persistence and bioaccumulation potential are not fully studied. Natural fragrance alternatives may have a lower environmental footprint.

Good to know

  • This ingredient is often listed near the end of an INCI list, indicating a low concentration.
  • Fragrance ingredients are not required to be individually disclosed on labels, so this may be part of a proprietary fragrance blend.

Common questions

What is Hexahydro-Tetramethyl-Methanoazulen-5-Yl Methyl Ketone in beauty products?

This is a man-made chemical used to give skincare and beauty products a pleasant woody or amber-like smell. It doesn't moisturize, treat, or improve your skin—it's purely for fragrance. While generally considered safe at low levels, it can sometimes cause irritation or allergic reactions, especially if you have sensitive skin.

What does Hexahydro-Tetramethyl-Methanoazulen-5-Yl Methyl Ketone do in a beauty product?

It evaporates from the skin's surface, releasing aromatic molecules that your nose perceives as a warm, woody scent. It has no active effect on skin structure or function.

Is Hexahydro-Tetramethyl-Methanoazulen-5-Yl Methyl Ketone safe for most people?

Generally recognized as safe for most people at low concentrations used in cosmetics. However, it can cause skin irritation or allergic reactions in sensitive individuals. The Cosmetic Ingredient Review (CIR) has not specifically evaluated this compound, but similar synthetic fragrances are considered safe with restrictions.

Who should be careful with Hexahydro-Tetramethyl-Methanoazulen-5-Yl Methyl Ketone?

Individuals with sensitive, reactive, or eczema-prone skin Anyone with a known fragrance allergy

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.