Bromate is a disinfection byproduct generated by ozonation during drinking water purification. It is undesirable, because it is a suspected human carcinogen. Water suppliers as well as manufacturers of bottled and mineral water need to comply with the limit values set by the respective public authority. The World Health Organization (WHO) sets the maximum contamination level for public water systems at 10 μg/L. In Europe the maximum acceptable concentration of bromate in mineral waters is set to 3 μg/L. Further lowering of these values are under discussion. ISO 11206 describes the determination of bromate in drinking water by IC with UV detection after post-column reaction. Bromate oxidizes iodide in acid solution to iodine. The excess iodide forms with the iodine the triiodide ion (I3-), which absorbs at 352 nm. The present application allows quantification of bromate down to 1 μg/L and below.