The degradation of the herbicide atrazine in aqueous medium (initial concentration of 100 mu g l(-1)) has been studied by electrooxidation process using Ti/IrO2 and Ti/SnO2 circular anode electrodes. The performance of the electrolytic cell resulted from its capability of reacting on the pollutants by using indirect effect of electrical current where active chlorine is electrochemically generated. A factorial experimental design was firstly used for determining the influent parameters on the herbicide atrazine degradation. The current intensity and treatment time were the main influent parameters on the degradation rate. Using a 24 factorial matrix, the best performance for atrazine degradation (removal of 95%) was obtained by selecting Ti/IrO2 anode operated at a current intensity of 2.0 A during 40 min of treatment time in the presence of 1.0 g NaCl l(-1). Then, the optimal experimental parameters for atrazine degradation have been investigated by using a Central Composite methodology. Under the optimal conditions determined by this method, electrooxidation can economically be applied to oxidise atrazine (73% of degradation for a total cost of 0.057 US$ m(-3)) while using Ti/IrO2 anode operated at a current intensity of 1.4 A during 22 min of treatment time in the presence of 1.0 g NaCl l(-1). (C) 2010 Elsevier B.V. All rights reserved.