What Is C12-13 Pareth-5 Carboxylic Acid?
C12-13 Pareth-5 Carboxylic Acid is a synthetic cleansing ingredient made from medium-chain fatty alcohols that have 12 to 13 carbon atoms. These fatty alcohols are usually sourced from renewable plant oils such as coconut or palm. They are first reacted with about five units of ethylene oxide to create an ethoxylated chain, then further processed so that one end of the molecule carries a carboxylic acid group. The result is a mild, water-soluble surfactant that can lift away oil and dirt while remaining gentle on skin.
The broader family of ethoxylated surfactants emerged in the late twentieth century as formulators looked for alternatives to harsher soaps. By adding a carboxylic acid group chemists improved the molecule’s ability to form stable, skin-friendly solutions across a wide pH range. Over the years this ingredient has secured a place in rinse-off products where mildness and effective cleansing are equally important.
You will most often spot C12-13 Pareth-5 Carboxylic Acid in facial cleansers, body washes, shampoos, micellar waters, makeup removers and baby bath products. Occasionally it is also included in masks or exfoliating gels to help these formulas rinse clean without leaving residue.
C12-13 Pareth-5 Carboxylic Acid’s Cosmetic Benefits/Uses
In cosmetics this ingredient serves one main purpose that offers several practical advantages for formulators and consumers alike.
Cleansing: As a non-ionic surfactant it loosens oil, sweat and makeup then suspends these impurities so they can be rinsed away with water. Compared with traditional soaps it produces a gentler lather, helps maintain the skin’s natural moisture balance and works well in hard-water conditions.
Who Can Use C12-13 Pareth-5 Carboxylic Acid
This mild surfactant suits most skin types, including normal, oily, combination and dry complexions, because it cleans without stripping natural oils. Sensitive or eczema-prone skin can usually tolerate it as well, thanks to its low irritation profile, though individuals who react easily to any surfactant should stay alert for redness or tightness.
The ingredient is manufactured from plant-derived fatty alcohols and petrochemical ethylene oxide, with no animal-derived components used in the process, so it is considered acceptable for vegans and vegetarians.
Current safety data show no specific risks for those who are pregnant or breastfeeding. This is not medical advice; anyone who is expecting or nursing should consult a healthcare professional before adding new skincare products.
C12-13 Pareth-5 Carboxylic Acid does not absorb UV light or make skin more sensitive to the sun, so it is not linked to photosensitivity. It also plays well with most other common cosmetic ingredients, including acids, vitamins and botanical extracts.
Potential Side Effects/Adverse Reactions
Responses to topical C12-13 Pareth-5 Carboxylic Acid vary from person to person. The points below list potential, though uncommon, side effects. When used at appropriate concentrations in properly formulated products most users will not experience any of these issues.
- Mild skin irritation or stinging, especially on compromised or very sensitive skin
- Transient dryness or tightness if the cleanser is left on the skin for an extended period
- Eye irritation if the product accidentally enters the eyes
- Rare allergic contact dermatitis presenting as redness, itching or small bumps
- Scalp dryness or flakiness when used in shampoos on already dry scalp conditions
If any burning, rash or persistent discomfort occurs discontinue use and seek medical advice if symptoms do not subside promptly.
Comedogenic Rating
Rating: 1 / 5
C12-13 Pareth-5 Carboxylic Acid is highly water soluble and designed to rinse completely off the skin. Because it does not leave an oily film or sit in pores it has a very low likelihood of clogging them. Its rating of 1 reflects a minimal but not entirely zero risk, mainly for people who are extremely reactive to any surfactant. Overall it is considered suitable for those prone to acne or breakouts.
Since this ingredient is usually found in wash-off formulas any brief residue is quickly removed, further lowering the chance of pore blockage.
Summary
C12-13 Pareth-5 Carboxylic Acid is a mild non-ionic surfactant that lifts oil makeup and daily grime then allows them to rinse away with water. By combining a plant-derived fatty alcohol backbone with ethoxylated links and a carboxylic acid group it stays gentle across different pH levels and water hardness, giving cleansers a soft lather without stripping natural moisture.
It is not one of the most talked-about ingredients but formulators appreciate its balance of mildness and cleaning power so it shows up in a fair number of quality rinse-off products.
Current safety data rate it as low risk for irritation or sensitization when used as directed. Still, skin can be unpredictable so it is wise to do a quick patch test before fully incorporating any new product that contains this ingredient.