DETERMINATION OF MERCURY BY ELECTROTHERMAL ATOMIC-ABSORPTION SPECTROMETRY USING DIFFERENT CHEMICAL MODIFIERS OR A SLURRY TECHNIQUE

The applicability of different chemical modifiers for thermal stabiliz ation and ETAAS determination of mercury is studied. The modifier effe ct is strongly influenced by the type of acid and acid content in the sample solution. A method is described for mercury determination in tu na fish and sediment after high pressure digestion with nitric acid, u sing thioacetamide (TAG) as chemical modifier. The method permits dete rmination of 0.5 mu g g(-1) mercury. A simpler and faster procedure us ing a slurry technique for the determination of mercury in reference m aterials (tuna fish, spinach, cabbage and sediments) was also evaluate d. Optimal instrumental parameters for mercury determination in slurri es are presented. On the basis of the results obtained a new procedure which allows determination of 0.1 mu g g(-1) mercury was developed.