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Limonene

Description

Limonene is a naturally occurring cyclic terpene found abundantly in the essential oils of citrus fruits, particularly lemons and oranges. This colorless liquid hydrocarbon possesses a fresh, citrusy aroma and is widely used in skincare formulations for its fragrance and potential therapeutic properties.

In skincare, limonene functions as a penetration enhancer, facilitating the absorption of other active ingredients. It exhibits antimicrobial and anti-inflammatory properties, potentially aiding in the treatment of acne and other skin infections. Some studies suggest limonene may have antioxidant effects, helping to neutralize free radicals and protect skin from oxidative stress.

However, limonene can be a skin sensitizer and irritant for some individuals, especially when oxidized. It is prone to oxidation when exposed to air, potentially leading to the formation of allergenic compounds. As a result, proper formulation and storage are crucial to maintain its stability and minimize the risk of adverse reactions.

Limonene is regulated in cosmetics and must be declared on ingredient lists when present above certain concentrations. Its use is generally considered safe when formulated appropriately, but patch testing is recommended for individuals with sensitive skin or known citrus allergies.