What Is C40-60 Pareth-10?
C40-60 Pareth-10 is a synthetic ingredient made by taking very long chain fatty alcohols that contain 40 to 60 carbon atoms and attaching about ten units of ethylene oxide to each molecule. These long chain alcohols can come from natural oils such as coconut or palm as well as petroleum-derived sources. The ethoxylation step happens in a controlled reactor where ethylene oxide gas is added to the heated alcohol under pressure, creating a wax-like material that disperses easily in both water and oil. Chemists began using this class of ingredients in the 1970s when formulators needed reliable surfactants that were mild yet effective, and the material quickly found a home in cosmetics because of its versatility.
Today C40-60 Pareth-10 appears in a wide range of products including facial cleansers, body washes, makeup removers, moisturizers, sunscreens, night creams, hair conditioners and clay or sheet masks. Its dual ability to mix oil and water while lifting away dirt helps brands create stable, pleasant textures that rinse clean without leaving a heavy film.
C40-60 Pareth-10’s Cosmetic Benefits/Uses
In formulas this ingredient delivers two key technical roles that translate into visible product benefits.
- Cleansing: The molecule’s water-loving and oil-loving parts allow it to surround oils, makeup and daily grime so they can be rinsed away with water. This gives face and body washes a thorough yet gentle clean that does not overly strip the skin or hair.
- Emulsifying: By positioning itself at the boundary between oil and water, C40-60 Pareth-10 keeps creams, lotions and sunscreens from separating. A stable emulsion feels smoother, spreads more evenly and delivers active ingredients consistently throughout the product’s shelf life.
Who Can Use C40-60 Pareth-10
C40-60 Pareth-10 is considered suitable for most skin types. Its mild cleansing action makes it friendly for normal, oily and combination skin while the long fatty chain helps buffers dryness so those with dry or mature skin generally tolerate it well. Very sensitive or compromised skin may still prefer shorter contact times since any surfactant can provoke irritation if left on too long.
The ingredient can be sourced from plant oils or petroleum but not from animals, so finished products using vegetable or synthetic feedstocks are normally acceptable for vegans and vegetarians. Consumers who follow a strict plant based lifestyle may want to confirm the origin with the manufacturer.
No research suggests a risk to pregnant or breastfeeding women when C40-60 Pareth-10 is applied topically in cosmetic amounts. The molecule is large, sits mainly on the skin surface and is unlikely to reach systemic circulation. This is not medical advice and anyone who is pregnant or nursing should show the full ingredient list of any product they intend to use to their healthcare provider.
C40-60 Pareth-10 does not absorb UV light and is not known to cause photosensitivity. It can be worn during the day without increasing the skin’s sensitivity to sunlight.
Potential Side Effects/Adverse Reactions
Reactions to any cosmetic ingredient vary between individuals. The points below describe potential side effects of topical C40-60 Pareth-10 although most people will not experience them when the ingredient is used at standard cosmetic levels.
- Mild skin irritation such as redness itching or stinging, especially on very sensitive skin
- Dryness or tightness if used in a high concentration or left on the skin for prolonged periods
- Eye irritation if the product accidentally gets into the eyes
- Contact allergy presenting as a rash or small bumps, considered rare
Discontinue use and seek medical advice if you develop persistent irritation or any other unexpected reaction while using a product containing C40-60 Pareth-10.
Comedogenic Rating
Rating: 1/5. C40-60 Pareth-10 is a large, highly ethoxylated molecule that tends to sit on the skin surface and is typically used in low amounts or rinse-off formulas, so it is very unlikely to clog pores. Its long fatty chain is balanced by the water-loving ethylene oxide units, making the ingredient more soluble and easier to wash away than simple waxes or oils.
This low score means the ingredient is generally suitable for people who are prone to acne or breakouts. If a product also contains heavy oils, butters or silicones, the overall formula could still be pore-clogging so always consider the full ingredient list.
Summary
C40-60 Pareth-10 works primarily as a cleanser and emulsifier. Its oil-friendly tail grabs onto sebum, makeup and sunscreen while the water-loving head lets those impurities rinse away. The same dual nature positions the molecule at the oil-water interface of creams and lotions, stopping them from separating so you get a smooth, stable texture from the first pump to the last.
The ingredient is fairly common in modern skincare and haircare, especially in gentle face washes and lightweight moisturizers, though it is not as famous as big-name actives like hyaluronic acid or niacinamide. Formulators value it for its reliability and mildness.
Safety data show C40-60 Pareth-10 to be low-risk for irritation or sensitization when used at cosmetic levels. Still, individual skin can react unpredictably so it is always smart to patch test any new product that contains this or any other surfactant before applying it to larger areas.