Advanced oxidation treatment and photochemical fate of selected antidepressant pharmaceuticals in solutions of Suwannee River humic acid

► We elucidate the photochemical degradation of three antidepressant pharmaceuticals. ► Hydroxyl radical is the most significant contributor to the degradation. ► Excited state dissolved organic matter also plays a significant role for duloxetine. ► Tentative reaction byproducts are identified.