Evaluation of a slurry technique for the determination of lead in spinach by electrothermal atomic-absorption spectrometry

Abstract

A simple method for the determination of lead in spinach involving minimum sample preparation is described. The powdered spinach is suspended in a thixotropic thickening agent, Viscalex HV30, and the slurry is injected directly into the electrothermal atomiser. Oxygen is introduced during the ashing stage to allow the use of higher ash temperatures and to avoid the build up of carbonaceous residue in the tube. Concentrations of powdered spinach up to 10%m/V can be tolerated in the suspension. Good agreement was achieved between results obtained by a standard additions procedure and by direct calibration with aqueous standards, and also by an alternative wet digestion procedure.