What Is Sodium Trideceth-8 Carboxylate?
Sodium Trideceth-8 Carboxylate is a synthetic surfactant made by joining a tridecyl alcohol chain with eight units of ethylene oxide, then adding a carboxyl group that is neutralised with sodium. This structure lets one end of the molecule love water while the other end loves oil, a mix that makes it useful for lifting dirt and oils from the skin or hair. The ingredient was first explored in the late twentieth century when formulators looked for milder, more versatile cleansers than traditional soaps. By tweaking the length of the alcohol chain and the number of ethylene oxide units, chemists created a version that balances cleaning power and gentleness, leading to its growing presence in personal care.
Production begins with fatty alcohols sourced from coconut or palm kernels. These alcohols react with ethylene oxide in a controlled process called ethoxylation, adding eight oxyethylene units. The resulting material is then carboxymethylated and neutralised with sodium hydroxide, yielding a stable, water-soluble powder or liquid.
You will most often spot Sodium Trideceth-8 Carboxylate in facial cleansers, body washes, micellar waters, shampoos, bubble baths and makeup removers. It can also appear in masks or exfoliating products that need a mild foaming agent to rinse away residues easily.
Sodium Trideceth-8 Carboxylate’s Cosmetic Benefits/Uses
This ingredient earns its place on an ingredient list because it performs key jobs that keep a formula effective and pleasant to use.
- Cleansing: Its surfactant nature lowers the surface tension of water so oils, dirt and makeup can be lifted and rinsed away without harsh scrubbing. This leaves skin or hair feeling clean yet comfortable.
- Foaming: It builds a soft, airy lather that spreads the product evenly and gives users the sensory cue that the product is working, all while helping active ingredients distribute across the surface.
Who Can Use Sodium Trideceth-8 Carboxylate
Sodium Trideceth-8 Carboxylate is generally well tolerated by most skin types, including dry, oily and combination skin, because it is milder than traditional soap-based cleansers. Sensitive skin users usually do fine with it too, though those who react easily to surfactants may still prefer a patch test in another part of the routine.
The fatty alcohols used to make this ingredient are most often sourced from coconut or palm plants, and no animal by-products are introduced during processing. That makes the finished material suitable for vegetarians and vegans.
Pregnant or breastfeeding individuals can typically use products that contain Sodium Trideceth-8 Carboxylate as it is not known to penetrate deeply or cause systemic effects. This is not medical advice and anyone who is pregnant or nursing should run all skincare products past a qualified physician just to be safe.
The ingredient does not increase photosensitivity, so it will not make skin more prone to sunburn. It can be used morning or night without special sun precautions beyond the usual daily SPF recommendation.
Potential Side Effects/Adverse Reactions
Responses to topical Sodium Trideceth-8 Carboxylate vary from person to person. The points below list potential side effects that could occur, though they are unlikely in most users when the ingredient is used correctly in a finished product.
- Temporary eye irritation if the formula accidentally gets into the eyes during use
- Mild skin dryness or tightness especially in those who already have very dry or compromised skin barriers
- Redness or itching in rare cases of individual sensitivity to ethoxylated surfactants
- Contact dermatitis in extremely rare instances where an allergy to the ingredient itself or to residual processing agents exists
If any of these reactions occur stop using the product and consult a healthcare professional for guidance.
Comedogenic Rating
Rating: 1 (very low likelihood of clogging pores)
Sodium Trideceth-8 Carboxylate is a fully water-soluble surfactant that rinses away cleanly without leaving behind oily or waxy residues that could block pores. Its molecular structure prefers to stay in water rather than embed itself in skin lipids, which is why it earns a near non-comedogenic score. Formulas that rely on this ingredient for cleansing rarely have high levels of heavy emollients, further reducing clogging risk.
Suitable for acne-prone or breakout-prone skin.
As always, pore-clogging potential also depends on the rest of the formula and how thoroughly the product is rinsed off.
Summary
Sodium Trideceth-8 Carboxylate is a mild synthetic surfactant that tackles two key jobs: it pulls dirt oil and makeup off the skin or hair and whips up a gentle foam that spreads the cleanser evenly. The molecule’s water-loving head and oil-loving tail let it surround grime so it can be washed away with ease, all while feeling softer than traditional soap.
You will spot this ingredient fairly often in modern facial cleansers, micellar waters and body washes, though it is not as famous as powerhouse surfactants like Sodium Laureth Sulfate. Brands looking for a balance of cleansing power and mildness keep reaching for it, so its presence is slowly growing.
Overall it is considered safe for daily use with low irritation and virtually no comedogenic risk. Still, every skin is unique so it is wise to patch test any new product that contains this ingredient before fully adding it to your routine.