Ingredient review
Thiomorpholinone
INCI: Thiomorpholinone
Thiomorpholinone is a synthetic fragrance ingredient with limited safety data; use with caution if you have sensitive skin.
In plain English
Thiomorpholinone is a man-made chemical used to add scent to cosmetics and skincare products. It belongs to a class of compounds called heterocycles, which have a ring structure containing sulfur and nitrogen. Because it's primarily a fragrance ingredient, it doesn't provide any skin benefits like hydration or anti-aging. Its main job is to make a product smell pleasant. However, like many fragrance ingredients, it can be a potential irritant, especially for people with sensitive or reactive skin. There is not a lot of published research on thiomorpholinone specifically in cosmetics, so its long-term safety profile is less established compared to more common ingredients.
Review score
Safety, usefulness, and evidence
Higher-caution ingredient
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
Quick decision guide
Read the cautions before using
Thiomorpholinone 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.
- Step 1Start with the score, then check the irritation and clogging risk before judging Thiomorpholinone.
- 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
moderateCan bother some users, especially with frequent use, damaged skin, or strong companion ingredients.
Clogging risk
lowLess likely to feel heavy or contribute to clogged pores for most skin types.
Evidence level
emergingThe ingredient may be promising, but claims should be treated more cautiously.
What it is
Thiomorpholinone is a synthetic organic compound with a six-membered ring containing one sulfur atom and one nitrogen atom. It is used as a fragrance ingredient in cosmetics and personal care products.
How it works
In a cosmetic product, thiomorpholinone contributes to the overall fragrance profile. It does not have any known functional benefits for the skin or hair beyond scent. It works by interacting with olfactory receptors to produce a specific odor.
Pros
Enhances product scent
Thiomorpholinone can contribute to a pleasant fragrance experience, making the product more enjoyable to use.
Low comedogenic risk
It is unlikely to clog pores, making it suitable for non-acneic skin types when used in low concentrations.
Cons and cautions
Limited safety research
There is minimal published data on thiomorpholinone's long-term effects in skincare, so its safety profile is less established than many common ingredients.
Potential irritant
As a synthetic fragrance, it may cause irritation, redness, or allergic contact dermatitis, especially in those with sensitive skin.
Best for
- People without fragrance sensitivities who enjoy scented products
- Those using products where the fragrance is well-tolerated
Use caution if
- Individuals with sensitive, reactive, or allergy-prone skin
- Anyone following a fragrance-free skincare routine
Usage tips
Safety summary
Thiomorpholinone is considered safe for use in cosmetics at low concentrations, but due to limited research and its role as a fragrance, it poses a moderate irritation risk for sensitive individuals.
Research notes
Published peer-reviewed studies on thiomorpholinone in cosmetics are scarce. Most safety data comes from general fragrance ingredient assessments, which indicate potential for skin sensitization at higher concentrations.
Common label clues
- Typical concentration
- Very low, typically less than 0.1% in finished products
- Regulatory status
- Approved for use as a fragrance ingredient in cosmetics in the EU and US, but subject to general safety requirements for fragrance allergens.
- Common uses
- Fragrance formulations, Scented personal care products
- Environmental note
- As a synthetic compound, its environmental persistence and biodegradability are not well-documented; limited data available.
Good to know
- Thiomorpholinone is not a common ingredient in mainstream skincare; it appears more often in niche or specialty fragrances.
- Fragrance ingredients are often listed simply as 'fragrance' or 'parfum' on labels, so you may not see thiomorpholinone listed individually.
Common questions
What is Thiomorpholinone in beauty products?
Thiomorpholinone is a man-made chemical used to add scent to cosmetics and skincare products. It belongs to a class of compounds called heterocycles, which have a ring structure containing sulfur and nitrogen. Because it's primarily a fragrance ingredient, it doesn't provide any skin benefits like hydration or anti-aging. Its main job is to make a product smell pleasant. However, like many fragrance ingredients, it can be a potential irritant, especially for people with sensitive or reactive skin. There is not a lot of published research on thiomorpholinone specifically in cosmetics, so its long-term safety profile is less established compared to more common ingredients.
What does Thiomorpholinone do in a beauty product?
In a cosmetic product, thiomorpholinone contributes to the overall fragrance profile. It does not have any known functional benefits for the skin or hair beyond scent. It works by interacting with olfactory receptors to produce a specific odor.
Is Thiomorpholinone safe for most people?
Thiomorpholinone is considered safe for use in cosmetics at low concentrations, but due to limited research and its role as a fragrance, it poses a moderate irritation risk for sensitive individuals.
Who should be careful with Thiomorpholinone?
Individuals with sensitive, reactive, or allergy-prone skin 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.