Pentadecalactone Dårligst Fragrance Synthetic and Natural No known benefits Pentadecalactone at a glance A fragrant skin care ingredient with a musky, powdery scent Also referred to as cyclopentadecanolide Can sensitize skin due to volatile aromatic compounds Is also used in the personal care and household goods industries Pentadecalactone description Pentadecalactone is a lactone (chemically, a cyclic ester) and synthetic fragrance used in cosmetics for its musky, powdery scent. It’s often also referred to as cyclopentadecanolide. Although the synthetic form of this ingredient is used in cosmetics, pentadecalactone is also found in Angelica root oil and produced naturally as a pheromone by apocrine sweat glands in male armpits. Research has proven this fragrant ingredient can sensitize skin. Pentadecalactone contains volatile aromatic compounds that can cause short-term and long-term sensitization including dryness, flaking and tightness. In lighter-to-medium skin tones this sensitization can appear as redness and in darker skin tones it can appear as purple, ashy or darkened spots on skin. Outside of the cosmetics industry, pentadecalactone is used in the household goods industry as a fragrance in products ranging from dryer sheets to cleaners.