Ingredient review
Trimethyl Cyclohexenyl Butanone
INCI: TRIMETHYL-1-CYCLOHEXENYLBUTAN-2-ONE
A synthetic floral scent compound that is generally safe at low levels but may cause allergic reactions in sensitive individuals.
In plain English
This is a man-made chemical that smells like violets or flowers. It's added to skincare and beauty products to give them a pleasant scent. In very small amounts, it's considered safe for most people, but a small number of people may develop an allergic reaction to it over time.
Review score
Safety, usefulness, and evidence
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
Quick decision guide
Useful, but context matters
Trimethyl Cyclohexenyl Butanone 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.
- Step 1Start with the score, then check the irritation and clogging risk before judging Trimethyl Cyclohexenyl Butanone.
- Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
- 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
lowLess likely to sting, burn, or bother most users, though sensitive skin can still react.
Clogging risk
lowLess likely to feel heavy or contribute to clogged pores for most skin types.
Evidence level
moderateThere is useful support, but formula details and claim strength still matter.
What it is
A synthetic fragrance ingredient chemically related to ionones, which are naturally found in some flowers like violets. It is produced in a lab to create a consistent, pleasant floral scent.
How it works
It works by binding to scent receptors in the nose, creating the perception of a floral, violet-like aroma. In a cosmetic product, it simply adds fragrance; it does not have any active skincare benefits like moisturizing or anti-aging.
Pros
Pleasant floral scent
Adds a natural violet-like aroma that many people find appealing, improving the overall user experience.
Low irritation at low levels
When used in small amounts, it has a low risk of causing immediate skin irritation for most users.
Cons and cautions
Potential allergen
Repeated exposure can lead to contact allergy in some people, causing redness, itching, or rash.
No skincare benefit
This ingredient only provides scent and does not improve skin hydration, texture, or health.
Best for
- People who enjoy scented skincare products
- Those without known fragrance allergies
Use caution if
- Individuals with known fragrance allergies or sensitive, reactive skin
Usage tips
Safety summary
Generally safe for most people at low concentrations, but it is a recognized contact allergen. Those with fragrance sensitivities should avoid it.
Research notes
Research shows that ionone derivatives can cause allergic contact dermatitis in a small percentage of the population. Regulatory bodies like the EU require labeling when present above 0.01% in leave-on products.
Common label clues
- Typical concentration
- Typically less than 1% in leave-on products
- Regulatory status
- Approved for use in cosmetics in the US and EU, but must be listed on the label if present above certain levels due to allergen potential.
- Common uses
- Fragranced moisturizers, Perfumes, Body lotions, Cleansers
- Environmental note
- As a synthetic compound, it is produced in a lab and does not rely on plant harvesting, but its environmental persistence is not well studied.
Good to know
- This ingredient is often listed simply as 'fragrance' or 'parfum' on labels.
- It is a common allergen that must be listed separately on EU cosmetic labels.
Common questions
What is Trimethyl Cyclohexenyl Butanone in beauty products?
This is a man-made chemical that smells like violets or flowers. It's added to skincare and beauty products to give them a pleasant scent. In very small amounts, it's considered safe for most people, but a small number of people may develop an allergic reaction to it over time.
What does Trimethyl Cyclohexenyl Butanone do in a beauty product?
It works by binding to scent receptors in the nose, creating the perception of a floral, violet-like aroma. In a cosmetic product, it simply adds fragrance; it does not have any active skincare benefits like moisturizing or anti-aging.
Is Trimethyl Cyclohexenyl Butanone safe for most people?
Generally safe for most people at low concentrations, but it is a recognized contact allergen. Those with fragrance sensitivities should avoid it.
Who should be careful with Trimethyl Cyclohexenyl Butanone?
Individuals with known fragrance allergies or sensitive, reactive skin
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.