DETERMINATION OF COPPER, IRON, MANGANESE AND ZINC IN RIVER AND ESTUARINE WATER BY ATOM TRAPPING-FLAME ATOMIC-ABSORPTION SPECTROMETRY

A simple method is described for the atomic absorption (AA) determination of Cu, Fe, Mn and Zn in river and estuarine water using two atom trapping techniques: a water-cooled dual silica tube and a commercially available double-slotted quartz tube mounted in an airacetylene flame. Rapid, accurate analyses can be achieved using continuous aspiration. The concentration detection limits were 0.9, 1.5 and 0.3 ng ml-1 for Cu, Mn and Zn, respectively, using a 2 min in situ preconcentration time with the dual silica tube atom trap and 4.0, 12.1, 2.0 and 1.2 ng ml-1 for Cu, Fe, Mn and Zn, respectively, using the double-slotted quartz tube. The relative standard deviations are of the order of 2.9-6.9% for both techniques. The accuracy was assessed by analyses of NRCC SLRS-2 riverine and SLEW-1 estuarine water reference materials. Basic performance characteristics are also given for Ag, Bi, Cd, In, Pb and Tl using the dual silica tube atom trap.