What Is Chlorelleth-20?
Chlorelleth-20 is a plant-derived ingredient made by attaching about twenty units of ethylene oxide to the fatty alcohols obtained from Chlorella vulgaris oil. The microalga is grown in controlled tanks where light, nutrients and temperature are optimized for rapid biomass production. After harvesting, the algal oil is extracted then converted to fatty alcohols, which are finally ethoxylated to create the water-friendly Chlorelleth-20.
Interest in algae-based ingredients rose in the 1970s as formulators searched for renewable alternatives to petroleum-derived surfactants. Chlorelleth-20 gained popularity because it offers gentle cleansing along with the marketing appeal of a botanical source. Today it is produced at scale through eco-certified manufacturing that limits solvent use and recycles water.
You will most often spot Chlorelleth-20 in facial cleansers, micellar waters, cream or gel masks, lightweight moisturizers, makeup removers, baby wash formulas and certain anti aging serums where a mild yet effective surfactant or emulsifier is needed.
Chlorelleth-20’s Cosmetic Benefits/Uses
Formulators choose Chlorelleth-20 for two main reasons:
- Cleansing: The ingredient lowers surface tension so water can lift away dirt, excess oil and makeup without stripping the skin. Its algal fatty chain gives it a softer feel than many synthetic surfactants, helping leave skin comfortable after rinsing.
- Emulsifying: Chlorelleth-20 helps oil and water stay blended, creating stable lotions, creams and milky cleansers. A steady emulsion improves texture, prevents ingredient separation and keeps actives evenly distributed for consistent performance.
Who Can Use Chlorelleth-20
Because Chlorelleth-20 is a mild cleanser and emulsifier it is generally suitable for normal, oily, combination and even sensitive skin that reacts poorly to harsher surfactants. Dry or easily dehydrated skin can also tolerate it well since the fatty alcohol backbone helps reduce that tight squeaky feeling some cleansers leave behind. The ingredient has no properties that specifically aggravate acne so blemish-prone users may find it a gentle option as long as the overall formula is non-comedogenic.
Chlorelleth-20 is sourced from cultivated Chlorella algae rather than animal by-products which makes it acceptable for both vegans and vegetarians. The manufacturing process does not rely on animal-derived catalysts or processing aids commonly flagged by cruelty-free shoppers.
No data suggest that topical use poses a risk during pregnancy or breastfeeding. That said this is not medical advice and anyone who is pregnant or nursing should have a doctor review any skincare product before regular use to be safe.
The ingredient does not absorb UV light or alter the skin’s response to sunlight so it is not considered photosensitizing. It is also fragrance-free gluten-free and compatible with leave-on or rinse-off formats, giving formulators flexibility without adding known sensitizers.
Potential Side Effects/Adverse Reactions
Responses to Chlorelleth-20 vary from person to person. The following are potential side effects that could occur, though they are uncommon when the ingredient is used at typical cosmetic levels in a well-formulated product.
- Transient stinging or redness may appear if the product is left on very sensitive skin for an extended period
- Mild dryness can occur in people whose skin barrier is already compromised since the ingredient has light cleansing power
- Contact dermatitis is possible in individuals allergic to polyethylene glycol derivatives or algal proteins that might remain after processing
- Eye irritation may arise if a cleanser containing Chlorelleth-20 is rubbed directly into the eyes without thorough rinsing
- Follicular irritation on the scalp could show up when high-concentration shampoo bases are not adequately diluted during use
If any of these effects occur stop using the product and seek guidance from a medical professional or dermatologist.
Comedogenic Rating
Rating: 1 out of 5. Chlorelleth-20 is highly water soluble and normally used at modest levels, so it tends to rinse off the skin rather than linger in pores. Its fatty alcohol backbone is muted by the twenty ethylene oxide units, which lowers its occlusive nature and keeps pore clogging potential low. For most people, even those prone to breakouts, it is considered a safe choice in well-formulated products. If a formula also contains heavy oils or waxes the overall comedogenicity could rise, but the contribution from Chlorelleth-20 itself remains minimal.
Summary
Chlorelleth-20 cleanses by reducing surface tension so water can whisk away grime, and it emulsifies by keeping the oil and water parts of a product smoothly blended. These dual abilities come from its structure: an algae-derived fatty tail that grips oil, plus hydrophilic ethylene oxide units that love water.
It is not a household name like glycerin or hyaluronic acid, yet formulators appreciate it for its gentle touch and plant origin, so you will quietly find it in many modern cleansers, micellar waters and lightweight creams.
Current research and decades of safe use show a very low risk of irritation or allergy for the average user. Still, every skin is unique. When you pick up a new product containing Chlorelleth-20, do a quick patch test first so you can be confident it works for you.