TRACE-LEVEL DETERMINATION OF BROMATE IN OZONATED DRINKING-WATER USING ION CHROMATOGRAPHY

Bromate is one of the disinfection by-products produced by the ozonation of drinking water. The US Environmental Protection Agency is considering regulating bromate to the low mu g/l level. A method using ion chromatography has been developed which will quantify bromate at this level, even in the presence of high (mg/l) levels of common anions such as chloride and sulfate. A berate eluent system was used to improve the separation of bromate from chloride. The level of chloride in the sample was reduced by pretreating the sample using a silver-form cation-exchange resin. The lower chloride level allowed a larger sample volume and preconcentration which reduced the bromate method detection limit to 1 mu g/l.