C13-15 Alkane

C13-15 Alkane is a lightweight emollient/hydrocarbon solvent used at relatively high levels in moisturizers and makeup to improve slip and reduce transepidermal water loss. Clinically it is generally well-tolerated and considered non-sensitizing, but in highly compromised barriers (eczema, post-procedure) any solvent-like emollient can occasionally sting or feel irritating, so it is not truly inert. Given the very low but non-zero irritation potential in reactive patients, it fits best as exceptionally gentle rather than 0.0. Safety Notes: In commercial products, C13-15 Alkane is often used at low levels (~0.1–2%) as a slip agent/emollient in lotions, serums, sunscreens, and makeup where it supplements other emollients and improves sensory. Mid-to-high levels (5–30%) are common in anhydrous balms, primers, and silicone-free creams where it functions as a major emollient/solvent. The highest consumer-available levels (50–95%) occur in essentially anhydrous “face oils,” cleansing oils, and minimalist emollient concentrates where C13-15 Alkane serves as the primary carrier; it is used mainly in leave-on and oil-based rinse-off formats, with no specific FDA/EU maximum concentration limit when used as a cosmetic ingredient under standard safety substantiation.