Analiza azotanów i bromianów powstających podczas dezynsekcji wody ozonem

When the surface water to be treated contains bromides and ammonium salts, ozonation will stimulate the formation of bromates, nitrites and nitrates, which have been identified as potential cancerogenic species. The admissible concentration of nitrates defined in Polish Standards is 10 gN/m (which corresponds to ca. 44 gNO3/m3 ). In Germany, the admissible concentration of nitrites must not exceed 0.1 gN/m3 . In Poland, the admissible concentration ofbromates has not been established yet. The maximal admissible concentrations of bromates in drinking water recommended by US EPA and WHO range between 10 and 50mgBr03 /m3. Moreover, it is postulated that, in future, these levels should be decreased to 5 mg/m3 , as soon as appropriate methods have been developed to enable determination of such low bromate levels. The objective of the present study was to discuss the problems that have to be tackled when determining bromate and nitrate concentrations in municipal water by high-performance ion-exchange chromatograpliy (IC-HPLC) or other teclmiques. Our investigations fiave sliown that direct determinations of nitrates and bromates are feasible at concentrations of 2 gNO3/m3 and over 0.2 gBrO3/m3, respectively.