The determination of low nitrite concentrations in the presence of excess sodium chloride is demanding due to the small retention time difference of these two anions. Dual detection – conductivity and UV/VIS – is a powerful method for determining nitrite traces in a 20 g/L sodium matrix. The UV/VIS chromatogram displays no chloride interferences. The determination of ammonium traces in the presence of excess sodium is described in AN-C-145.