CD03 Watch out! Allergic contact dermatitis to acrylates in a smart watch

A 15-year-old girl with long-standing atopic dermatitis and hay fever presented to the patch test clinic with an atypical distribution of eczema over the trunk, elbows and perioral skin. Close examination additionally revealed a well-defined patch on the dorsal left wrist, at the exact site of her Apple smart Watch. She was a competitive swimmer and gym user. Her medications were tranexamic acid, topical steroids and emollients. Testing to the British Society for Cutaneous Allergy standard, medicaments, facial, oral, metals and acrylate series (applied on day 2) showed positive reactions to methylisothiazolinone (day 2+, day 4++), methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) (day 2+, day 4++), benzophenone-3 (day 2−, day 4+), benzophenone-4 (day 2−, day 4+), sodium benzoate (day 2−, day 4+), benzoyl peroxide (day 2−, day 4+), isobornyl acrylate (day 2+), ethylene glycol dimethacrylate (day 2+) and hexanediol diacrylate (day 2+). The benzophenones were of current relevance to her sun protection factor-containing emollient. Sodium benzoate was present in her shower gel and shampoo, as well as her favourite Vimto squash. Benzoyl peroxide was of unknown relevance and MI/MCI was thought to be of past relevance. The acrylates, in particular isobornyl acrylate, were postulated to be of current relevance to her Apple Watch. Since avoiding the allergens, including the Apple Watch, her eczema has significantly improved, specifically clearing at the wrist and perioral skin. Our patient had no known previous acrylate exposure, in particular no history of using gel or acrylic nails. The Apple product website declares that many of their products contain trace amounts of acrylates and methacrylates. Knowledge that acrylates are a common cause of allergic contact dermatitis (ACD) in diabetic devices, and strong clinical suspicion about the watch, prompted us to test with the acrylate series. There are two previous reported cases of Apple Watch ACD, both attributed to nickel (Levian B, Chan GC, Adler BL. Out of REACH: allergic contact dermatitis to nickel in an Apple Watch. Contact Dermatitis 2024; 90: 99–101; Ko WC, Yu J. Nickel allergy elicited by an Apple Watch. Dermatitis 2022; 33: e11–12). Nickel is mentioned on the Apple product website, but that states that release levels are low. Interestingly in one case the dimethylglyoxime spot test was negative (Levian et al.) and the acrylate series was not tested. Our patient tested negative to nickel. There are