An uncommon cause of swimmer's rash: Allergic contact dermatitis to persulfates in pools.

Allergic contact dermatitis (ACD) is an important diagnosis to consider in patients with dermatitis following specific exposures. Classically, ACD from persulfates is associated with hair-bleaching products and spa water/swimming pool exposure and is most commonly reported in adult men. We report a case of ACD to potassium peroxymonopersulfate (PPMS), a common pool "shocking" chemical, in a 7-year-old boy presenting with recurrent and diffuse dermatitis triggered by swimming pool exposure.