The present work aims at demonstrating the application of UV/S2O82- system successfully for degradation of cetirizine dihydrochloride (CTZ) from aqueous waste. More than 95% CTZ was degraded within 90 min of UV irradiation. The degradation kinetics followed a pseudo-first order kinetics at all the experimental conditions studied. The studied process enhanced the biodegradability, BOD5/COD ratio from 0.15 to 1.94 of the aqueous wastewater. Acute toxicity test using Photobacterium phosphoreum showed that the degradation products are less toxic than the initial toxicity levels of CTZ. The sulfate radical generated from the photochemical decomposition of S2O82- shows that UV/S2O82- system is a kinetically favorable process in removing cetirizine hydrochloride from aqueous waste along with reduction of toxicity. (C) 2016 Elsevier B.V. All rights reserved.