Cetoleth-5: 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 24, 2025
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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 Cetoleth-5?

Cetoleth-5 is a synthetic ingredient made by reacting naturally derived fatty alcohols from vegetal oils such as coconut or rapeseed with ethylene oxide, adding an average of five ethoxy units to each fatty alcohol molecule. The base fatty alcohol mix contains mainly cetyl (C16) and oleyl (C18 unsaturated) chains, giving the material a balance of oil-loving and water-loving parts. This dual nature lets it blend oil and water in the same formula.

After nonionic surfactants became popular in the 1960s formulators looked for options that gave mild cleansing without the tight feel of soap. Ethoxylated fatty alcohols like Cetoleth-5 fit that need, so they began showing up in skin and hair care. The process to make it is straightforward: purified fatty alcohols are placed in a reactor, ethylene oxide gas is introduced under controlled heat and pressure then the mixture is neutralized and filtered to remove traces of catalyst.

Today Cetoleth-5 is found in a range of products including facial cleansers, shower gels, makeup removers, light lotions, sunscreens, sheet mask essences and rinse-off hair treatments. Formulators pick it because it is mild, works in many pH ranges and is compatible with most other ingredients.

Cetoleth-5’s Cosmetic Benefits/Uses

In cosmetics Cetoleth-5 delivers two key actions that improve how a formula feels and performs on the skin or hair

  • Cleansing: Its surfactant properties lift away oil, dirt and makeup so they can be rinsed off easily. Because it is nonionic it is less likely to strip skin of its natural lipids which helps maintain softness after washing
  • Emulsifying: By lowering the surface tension between water and oil phases it keeps creams, lotions and milky cleansers from separating. A stable emulsion means the product has a smooth texture, consistent dosage of active ingredients and a longer shelf life

Who Can Use Cetoleth-5

Cetoleth-5 is considered gentle enough for most skin types including normal, oily, combination and dry. Because it cleans without strong stripping it can be a good choice for sensitive skin too, though extremely reactive skin should still monitor for any discomfort. It is generally non comedogenic so acne-prone users can usually tolerate it.

The fatty alcohols used to make Cetoleth-5 are normally sourced from plant oils which makes the ingredient suitable for vegans and vegetarians as long as the finished product is certified to exclude animal-derived additives elsewhere in the formula.

No research suggests that topical use of Cetoleth-5 is unsafe during pregnancy or breastfeeding. This is not medical advice and anyone who is pregnant or nursing should ask their doctor before starting new skincare products to be certain they fit personal health needs.

Cetoleth-5 is not known to cause photosensitivity so it will not make skin more prone to sunburn. It also has no bleaching or staining effect on hair or fabrics, which can be helpful in leave-on products.

Potential Side Effects/Adverse Reactions

Individual responses to Cetoleth-5 vary. The points below outline possible but uncommon reactions when the ingredient is used topically in correctly formulated products. Most people will not experience these effects.

  • Mild skin irritation such as redness or stinging, especially on compromised skin barriers
  • Contact dermatitis in people allergic to ethoxylated compounds
  • Eye irritation if the product accidentally gets into the eyes
  • Dryness or tightness when used at high concentrations in rinse-off cleansers
  • Enhanced penetration of other actives, which may heighten their own irritation potential

If irritation or any adverse reaction occurs discontinue use immediately and consult a healthcare professional if symptoms persist.

Comedogenic Rating

Cetoleth-5 has a comedogenic rating of 1 out of 5. The ethoxylation process makes the molecule more water friendly than traditional fatty alcohols, so it is far less likely to clog pores. At the low to moderate use levels typical in finished formulas it rinses cleanly and leaves only a light, non occlusive film. Because of this it is generally suitable for people who are prone to acne or breakouts. As with any ingredient final pore clogging potential also depends on the whole formula, concentration and how thoroughly the product is removed.

Summary

Cetoleth-5 acts as a mild cleanser and a reliable emulsifier. Its balanced oil attracting and water attracting structure lifts away dirt and makeup while keeping water and oil phases blended so creams stay smooth and stable. Although it is not a headline making ingredient it shows up quietly in many everyday products like facial washes, lightweight lotions and makeup removers because formulators value its versatility and skin friendly profile.

The safety record of Cetoleth-5 is strong, with low irritation rates and no evidence of serious health concerns when used as directed. Still, skin can be unpredictable so it is wise to patch test any new product containing this ingredient to be certain it suits your individual needs.

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