Bromate Ion Analysis By Ion Chromatography

Bromate ion occurs during ozonation of bromide-containing waters. The current WHO guideline for bromate ion is 25 μg/L. Bromate analysis in drinking waters can be performed by various techniques. However, given the commonly low concentrations of bromate ion found in drinking waters, the classical methods do not fit for bromate analysis in most cases. A specific conductimetric method with anion suppression which enhances analyte detection by lowering the eluent conductivity is described in this paper for low bromate level analysis. Three eluents have been tested in order to have the best signal to noise ratio. Some other parameters likely to interfere in bromate ion detection (nitrate and sulfate in particular) are also investigated. Taking into account the results of three interlaboratory trials between six European laboratories, a 2 μg/L detection level for bromate can be established.