Toxicity of bromate ions in drinking water and its determination using ion chromatography with post column derivatisation

Disinfection of drinking water is usually carried out by chlorination. This is a well-known and effec-tive technology which has many advantages. However, during this process dangerous by-products such as trihalomethanes, as well as chlorate and chlorite are formed. The disinfection of bromide-containing source waters with ozone results in the production of bromate ions (BrO 3-), which are formed as a result of a series of complex reactions between ozone and bromide ions present in water. Bromates are possible human carcinogens. For these reasons trace analysis of bromate and other oxyhalides by-products in waters has received considerable attention in recent years. This article describes the determination of bromate in drinking water by IC with post column derivatisa-tion using NaBr/NaNO 2 and UV detection. The direct method allows the determination of bromate at low μg/dm3 levels and sample pretreatment is not necessary.