What Is C9-16 Alkane/Cycloalkane?
C9-16 Alkane/Cycloalkane is a mix of straight chain and ring shaped hydrocarbons that contain between nine and sixteen carbon atoms. These molecules are most often sourced from highly refined petroleum cuts, though some brands now obtain them from plants such as sugarcane through a process that turns natural sugars into hydrocarbons. The raw material is distilled to isolate the desired carbon range, then further purified and hydrogenated to remove impurities and odors, leaving a clear low-viscosity liquid.
Hydrocarbon oils have been used on skin since the early 1900s, first as mineral oil. Over time cosmetic chemists learned that shorter chain alkanes feel lighter and spread more easily, so the C9-16 fraction became popular in the 1990s as a modern alternative to heavier oils and silicones. Today it appears in many water-resistant sunscreens, makeup removers, facial cleansing balms, long-wear foundations, hair shine sprays, body oils, antiperspirants and even certain sheet masks where a light yet occlusive feel is needed.
C9-16 Alkane/Cycloalkane’s Cosmetic Benefits/Uses
This ingredient earns its place in formulas thanks to several helpful roles:
- Cleansing: Its oil-like nature quickly dissolves makeup, sunscreen and excess sebum so they can be wiped or rinsed away without stripping the skin
- Solvent: It thins waxes, pigments and UV filters helping them spread evenly and improving product texture and payoff
- Emulsifying: It helps keep oil and water phases mixed, supporting stable creams and lotions that do not separate on the shelf
Who Can Use C9-16 Alkane/Cycloalkane
C9-16 Alkane/Cycloalkane is generally compatible with most skin types. Its light texture suits oily, combination and normal skin because it leaves minimal residue, yet it still offers a soft occlusive layer that can benefit mildly dry skin. Extremely dry skin may need a richer oil or butter alongside it, while very acne-prone users should monitor for any congestion since any occlusive film can occasionally trap sebum and debris.
The ingredient is chemically inert and free of animal derivatives when sourced from petroleum or plant sugar feedstocks, so it can be suitable for vegans and vegetarians. Those following a strictly plant-only lifestyle should look for brands that specify a bio-based origin.
Because it is not absorbed into the bloodstream and lacks hormonal activity, topical use is considered low risk during pregnancy or breastfeeding. This is not medical advice and anyone who is pregnant or nursing should show the full ingredient list of any product to their doctor before use just to be safe.
C9-16 Alkane/Cycloalkane does not make skin more sensitive to sunlight and has no known effect on photosensitivity.
Potential Side Effects/Adverse Reactions
Responses to any cosmetic ingredient can vary from person to person. The issues below are possible but uncommon when a product is formulated and used correctly.
- Mild contact irritation or redness in individuals with very sensitive skin
- Clogged pores or blemishes on acne-prone areas if used in heavy layers or not removed thoroughly
- Transient stinging if the liquid accidentally reaches the eyes
- Folliculitis on the body when trapped under tight clothing or athletic gear
- Temporary respiratory discomfort if fine sprays are inhaled during application
If any irritation or unexpected reaction occurs stop using the product and consult a healthcare professional.
Comedogenic Rating
Rating: 1 / 5
C9-16 Alkane/Cycloalkane earns a low score because its molecules are small enough to spread easily yet still too large to penetrate deeply into pores. The liquid leaves only a thin occlusive layer that helps reduce moisture loss without creating the thick film associated with higher clogging risk oils. In lab tests and consumer use studies it shows minimal tendency to trigger comedones compared with heavier mineral oils or certain vegetable oils high in oleic acid.
Suitable for most people who are prone to acne or breakouts, provided the overall formula is light and the product is removed thoroughly at the end of the day.
One thing to note: when combined with very waxy or high-silicone formulas its low viscosity can help those other ingredients spread farther, so the finished product’s clogging potential depends on the full recipe not just this single component.
Summary
C9-16 Alkane/Cycloalkane acts as a cleanser, solvent, mild emulsifier and lightweight skin protectant. Its hydrocarbon structure dissolves makeup and sunscreen, thins out heavy waxes and pigments for smoother application, keeps oil and water phases blended and leaves a breathable barrier that slows moisture loss.
With its silky feel and low scent it has become a go-to alternative to silicone and dense mineral oil, showing up in everything from cleansing balms and micellar oils to long wear foundations and body sprays. While not yet as famous as jojoba or dimethicone its popularity keeps climbing thanks to its pleasant texture and versatility.
Current safety reviews rate it as low risk for irritation or systemic exposure and it carries a very low comedogenic rating. As with any new skincare or makeup product it is wise to patch test first to be sure your skin agrees with the full formula.