Sodium C12-15 Alketh-8 Carboxylate: What Is It, Cosmetic Uses, Benefits & Side Effects

Curious about this ingredient? In this article we're explaining exactly what it is and why it's used within cosmetic formulations.
Updated on: June 30, 2025
Share:
Inside this article:

We verify all information on this page using publicly available nomenclature standards from The Personal Care Products Council (PCPC), the European Commission's CosIng database and documentation provided directly by ingredient manufacturers. Our analysis is based on technical data from these sources to ensure accuracy and reliability.

What Is Sodium C12-15 Alketh-8 Carboxylate?

Sodium C12-15 Alketh-8 Carboxylate is a synthetic surfactant made by reacting fatty alcohols sourced from coconut or palm oil (with carbon chains ranging from 12 to 15) with ethylene oxide, then neutralizing the resulting ethoxylated acid with sodium hydroxide. The “8” in its name tells you the average number of ethylene oxide units attached to each alcohol chain, which helps the molecule mix oil and water. Surfactants like this began appearing in personal care formulas in the mid-20th century when manufacturers looked for gentler soap alternatives that could perform well in hard water. Today it is produced in large-scale reactors where temperature and pressure are carefully controlled to achieve a consistent degree of ethoxylation before the final sodium salt is formed, dried and milled into a powder or concentrated as a liquid. You will most often see Sodium C12-15 Alketh-8 Carboxylate in face cleansers, body washes, shampoos, makeup removers, foaming masks, anti-aging formulas that need mild cleansing properties, liquid hand soaps and even some micellar waters.

Sodium C12-15 Alketh-8 Carboxylate’s Cosmetic Benefits/Uses

Formulators reach for this ingredient because it is excellent at lifting dirt and oil without being too harsh on skin.

As a cleansing agent, it lowers the surface tension of water so grime, makeup and excess sebum can be rinsed away easily. Its balanced oil-in-water profile means it can generate a soft foam, work in a wide pH range and remain effective in both hard and soft water, helping products feel pleasant during use while leaving skin and hair fresh but not stripped.

Who Can Use Sodium C12-15 Alketh-8 Carboxylate

This surfactant is generally suitable for normal, oily and combination skin because it cleans effectively without leaving a tight or squeaky feel. Dry or very sensitive skin can usually tolerate it in well-balanced formulas, but if those skin types are already irritated or have conditions like eczema they might prefer richer cleansers with extra soothing agents.

The ingredient is made from plant-derived fatty alcohols and contains no animal by-products, so it fits vegan and vegetarian lifestyles. It is also commonly found in cruelty-free product lines.

No studies suggest a specific risk for pregnant or breastfeeding people when Sodium C12-15 Alketh-8 Carboxylate is used topically. Still, this is not medical advice and anyone who is expecting or nursing should review all personal care products with a healthcare professional just to be safe.

The molecule does not make skin more sensitive to sunlight, so it is not considered photosensitizing.

Potential Side Effects/Adverse Reactions

Responses to topical Sodium C12-15 Alketh-8 Carboxylate vary from person to person. The points below cover potential side effects, but most users will not experience them when the ingredient is properly formulated and used as directed.

  • Mild transient stinging especially if applied to broken or freshly shaved skin
  • Dryness or tightness in people with already compromised skin barriers
  • Redness or itching in rare cases of individual sensitivity
  • Eye irritation if the product accidentally gets into the eyes before rinsing

If any irritation or discomfort occurs stop using the product and consult a healthcare professional if symptoms persist.

Comedogenic Rating

Rating: 0-1 out of 5. Sodium C12-15 Alketh-8 Carboxylate is a water-soluble cleansing agent with no oily residue, so it does not linger inside pores or form films that could trap sebum. Formulas using it typically rinse away completely, which keeps pore blockage risk very low. Because the molecule is relatively large and ionic, it has little tendency to penetrate follicular openings where comedones start.

Suitable for acne-prone and breakout-prone skin in most rinse-off products.

As with any surfactant, the final product’s full ingredient mix and how long it sits on skin can influence pore-clogging potential, so overall formulation still matters.

Summary

Sodium C12-15 Alketh-8 Carboxylate is a plant-derived synthetic surfactant that lifts makeup, oil and daily grime by lowering water’s surface tension then rinses away cleanly. Its balanced chain length and eight ethylene oxide units let it foam gently, work across a broad pH span and perform even in hard water.

It shows up in a wide range of cleansers, shampoos and micellar waters, though it is not as famous as sulfate surfactants or glucosides. Brands opt for it when they need a mild yet effective cleanser that suits most skin types.

Current safety data rate it as low risk for irritation at the concentrations used in cosmetics, with no evidence of systemic toxicity. Still, skin can react unpredictably, so it is wise to patch test any new product that contains this ingredient before full use.

Was this article helpful?
More from Glooshi:
ADVERTISEMENT
Get all our top headlines in beauty.
Delivered right to your inbox each week. Zero spam, all goodness, opt-out at anytime.
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Get the latest beauty news, top product recommendations & brand-exclusive discount codes direct to your inbox.
Send good feedback:

All feedback is greatly appreciated, anonymous, and will be used to improve the quality of our articles.

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Send bad feedback:

All feedback is greatly appreciated, anonymous, and will be used to improve the quality of our articles.

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Search