BACKGROUND: Formaldehyde is a common preservative and strong sensitizer. OBJECTIVE: The aim of the study was to evaluate the release of formaldehyde from baby/toddler wet wipes using the chromotropic acid method (CAM). METHODS: An online search of best-selling baby wipes was conducted. None declared formaldehyde or formaldehyde-releasing preservatives. Standard CAM procedures were used: a 1 x 1-in square of fresh wipe was placed in a bottle with an open vial of 4 mg/1 mL of chromotropic acid and sulfuric acid solution, sealed, and stored for 48 hours. Formalin and water served as controls. A blinded investigator graded color change (negative, indeterminate, mild, moderate, or strong). For quality control, 20% of all samples as well as all positives were retested. RESULTS: Fifty-one popular and highly reviewed baby and toddler wet wipe products were tested using CAM. Twelve wipes (24%) released formaldehyde (8 mild, 4 moderate/strong). Chromotropic acid method testing of 9 wipes (18%) was indeterminate and 30 (59%) were negative. CONCLUSIONS: Almost one quarter of baby/toddler wet wipes released formaldehyde when evaluated with CAM. Patients and clinicians should be aware of this potentially undeclared source of this common allergen.