This study established a simple and efficient method for the determination of formaldehyde in dried shiitake mushrooms. Formaldehyde in mushrooms was extracted by a wet pretreatment procedure, followed by Ultraviolet-visible (UV-Vis) spectrophotometric analysis using an acidified pararosaniline reagent. The proposed method had a high sensitivity (a detection limit of 0.02 mg L(1) and a high recovery (90.3–96.5 %) with a relative standard deviation (%RSD) of 1.8(5.1 %. Formaldehyde levels in dried shiitake mushrooms collected in local markets (Ho Chi Minh City, Vietnam) ranged from 169.1 to 402.5 mg kg(1.
