SLURRY ATOMIZATION OF VEGETABLES FOR THE ELECTROTHERMAL ATOMIC-ABSORPTION SPECTROMETRIC ANALYSIS OF LEAD AND CADMIUM

Slurry-ETAAS procedures for the rapid determination of lead and cadmiu m in vegetables are described. Fast-programme methodology, in which th e drying and ashing stages are replaced by a single modified drying st ep, is used. Slurries are prepared in a 20% (v/v) ethanol medium using 0.1% ammonium dihydrogenphosphate as a chemical modifier. The suspend ing medium also contains hydrogen peroxide to prevent the build-up of carbonaceous residue inside the atomizer. Platform atomization using 1 800 degrees C and 1700 degrees C for lead and cadmium, respectively, p ermits calibration with aqueous standards. Results for two standard re ference materials confirm the reliability of the procedures.