Although NaN3 is frequently used as a biocide in many sorption experiments, a few recent reports have suggested that azide can react with the analyte of interest. Ro et al. (1995) reported that hydroxyatrazine and 3-ethylamino, 5-isopropylamino-s-triazinone were the final transformation products from chemical interactions between atrazine and NaN3 in anaerobic and aerobic conditions. Rügge et al. (1999) showed a decrease in atrazine in microcosm experiments with NaN3. In both cases, the decrease in the parent compound became more pronounced with increase in contact time