SLURRY-ELECTROTHERMAL ATOMIC-ABSORPTION SPECTROMETRIC METHODS FOR THEDETERMINATION OF COPPER, LEAD, ZINC, IRON AND CHROMIUM IN SWEETS AND CHEWING GUM AFTER PARTIAL DRY ASHING

Slurry-electrothermal atomic absorption spectrometric procedures for t he rapid determination of the copper, lead, zinc, iron and chromium co ntents of sweets and chewing gum samples are discussed. The samples we re first subjected to a process of mild calcination; suspensions were then prepared in a medium containing 8% ethanol as stabilizing agent, 0.1% ammonium dihydrogenphosphate as chemical modifier and 4% hydrogen peroxide to prevent the build-up of carbonaceous residues inside the atomizer. Fast-programme methodology was used for the heating programm es. Calibration was carried out using aqueous standards, and the relia bility of the procedures was verified by analysing several standard re ference materials.