Taking bromophenol blue as pollutant model, the role of sulfate electrolytes during the anodic oxidations was investigated in a wide range of concentrations (0.1-500 mM). Trials were performed with an electrochemical cell containing boron-doped diamond anode and stainless steel cathode. The impact of sulfate concentration on the degradation performance was assessed by comparing the color removal efficiencies at various time intervals. The results revealed a significant and peculiar influence of this parameter on the degradation efficiency. Thus, we emphasize the importance of selection of operating levels in electrolytic oxidations, especially when certain activators (from the cathode) may be formed in the treated solutions. (C) 2015 The Electrochemical Society.