Ingredient review
C12-15 Pareth-5
INCI: C12-15 PARETH-5
A synthetic emulsifier that helps cleansers work effectively, but may be drying or irritating for very sensitive skin.
In plain English
C12-15 Pareth-5 is a man-made ingredient that helps oil and water mix together in products like face washes and shampoos. It's a type of surfactant, which means it helps lift dirt and oil from your skin so they can be rinsed away. While it's effective, it can sometimes strip the skin's natural moisture barrier if used too often or in high amounts.
Review score
Safety, usefulness, and evidence
Potentially useful with some tradeoffs
The evidence base is useful, but some claims depend heavily on the formula.
Main practical flags: irritation is moderate; clogging risk is low.
- Source
- synthetic
- Evidence
- moderate
- Irritation
- moderate
- Clogging risk
- low
Quick decision guide
Useful, but context matters
C12-15 Pareth-5 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 C12-15 Pareth-5.
- 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
moderateThere is useful support, but formula details and claim strength still matter.
What it is
C12-15 Pareth-5 is a synthetic ethoxylated alcohol, meaning it's made by reacting a fatty alcohol (from the C12-15 carbon chain range) with ethylene oxide. It belongs to a class of ingredients called alkyl ethoxylates, which are widely used as mild surfactants and emulsifiers in personal care products.
How it works
In a cosmetic product, C12-15 Pareth-5 reduces the surface tension between oil and water, allowing them to blend into a stable emulsion. This helps cleansers effectively remove sebum, makeup, and environmental debris. It also helps other ingredients spread evenly across the skin.
Pros
Effective cleanser
Helps remove excess oil, dirt, and makeup without requiring harsh scrubbing.
Formula-friendly
Works well in a wide range of product textures, from gels to creams, improving stability and feel.
Cons and cautions
Potential for dryness
Frequent use in high concentrations can strip the skin's natural oils, leading to tightness or irritation.
Ethoxylation concerns
The manufacturing process can create trace amounts of 1,4-dioxane, a potential contaminant, though reputable brands keep levels within safe limits.
Best for
- People with normal to oily skin looking for effective cleansing
- Those who use rinse-off products like body washes and shampoos
Use caution if
- Individuals with very dry, sensitive, or eczema-prone skin who may find it too stripping
Usage tips
Safety summary
C12-15 Pareth-5 is considered safe for use in cosmetics at typical concentrations, but it can be drying or irritating for sensitive skin. The main safety concern is potential contamination with 1,4-dioxane, which is regulated and monitored by reputable manufacturers.
Research notes
Studies on alkyl ethoxylates indicate low acute toxicity and moderate skin irritation potential. The Cosmetic Ingredient Review (CIR) panel has evaluated similar ethoxylated alcohols and found them safe when formulated to minimize impurities.
Common label clues
- Typical concentration
- Typically 0.5% to 5% in rinse-off products; lower in leave-on formulas
- Regulatory status
- Approved for use in cosmetics in the US (FDA) and EU (CosIng) with concentration limits for leave-on products. Manufacturers are expected to minimize 1,4-dioxane contamination.
- Common uses
- Cleansers, Shampoos, Body washes, Makeup removers
- Environmental note
- Ethoxylated surfactants can be slow to biodegrade in aquatic environments. Some regions have restrictions on their use due to environmental persistence concerns.
Good to know
- C12-15 Pareth-5 is often used alongside other surfactants to create a balanced cleansing experience.
- The '5' in the name refers to the average number of ethylene oxide units, which influences its water solubility and mildness.
Common questions
What is C12-15 Pareth-5 in beauty products?
C12-15 Pareth-5 is a man-made ingredient that helps oil and water mix together in products like face washes and shampoos. It's a type of surfactant, which means it helps lift dirt and oil from your skin so they can be rinsed away. While it's effective, it can sometimes strip the skin's natural moisture barrier if used too often or in high amounts.
What does C12-15 Pareth-5 do in a beauty product?
In a cosmetic product, C12-15 Pareth-5 reduces the surface tension between oil and water, allowing them to blend into a stable emulsion. This helps cleansers effectively remove sebum, makeup, and environmental debris. It also helps other ingredients spread evenly across the skin.
Is C12-15 Pareth-5 safe for most people?
C12-15 Pareth-5 is considered safe for use in cosmetics at typical concentrations, but it can be drying or irritating for sensitive skin. The main safety concern is potential contamination with 1,4-dioxane, which is regulated and monitored by reputable manufacturers.
Who should be careful with C12-15 Pareth-5?
Individuals with very dry, sensitive, or eczema-prone skin who may find it too stripping
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.