Cinnamomum Zeylanicum Bark Extract

Cinnamomum zeylanicum (cinnamon) bark extract is a fragrance/botanical extract rich in cinnamaldehyde and related aromatic compounds that are well-documented irritants and can also act as contact allergens in patch testing. Even at the low concentrations typical for cosmetics, it can provoke burning, erythema, and eczema flares in sensitive or barrier-impaired skin, and cumulative exposure in a routine increases risk. Given its known irritant/allergenic profile and the high stakes for eczema-prone patients, it warrants a high irritancy score. Safety Notes: In commercial leave-on skincare, Cinnamomum Zeylanicum (Cinnamon) Bark Extract is most often used as a minor “botanical/antioxidant” component of blends, where it can appear at trace-to-low levels (~0.0005–0.05%), especially in sensitive-skin products due to fragrance-allergen/irritancy concerns. Higher concentrations are seen in consumer-available “warming,” “purifying,” or acne-focused products and some rinse-off masks/cleansers, where it is used more deliberately for sensory effect and can reach ~0.5–2.0% in the finished formula (with rinse-off products generally tolerating the upper end more readily than leave-on). The upper bound reflects observed OTC specialty formulations while staying below levels more typical of essential oil–driven or professional-use products.