Simultaneous determination of bromide, bromate and nitrite in low μg l−1 levels by ion chromatography without sample pretreatment

A new ion chromatographic method has been developed for the simultaneous analysis of the major matrix anions (chloride, nitrate, phosphate, sulfate, etc.), lower concentrated bromide, oxyhalides (iodate, chlorite, bromate) and nitrite in fresh waters and sea water. The method is based on an anion exchange chromatographic separation followed by a sequential analysis through conductivity and subsequent postcolumn reaction with UV detection. Whereas the matrix anions are quantified by conductivity, the oxyhalides and nitrite are measured by the oxidation product I3− which they generate from iodide in the postcolumn reaction. The detection limits as determined for bromide, bromate and nitrite are 3, 0.1 and 0.5 μg l−1, respectively.