Determination of Zinc, Cadmium and Lead in Untreated Sugar Samples by Anodic Stripping Voltammetry

Abstract

Trace amounts of zinc, cadmium and lead were determined in refined beet sugar by differential-pulse anodic stripping voltammetry (DPASV) at a hanging mercury drop electrode. Measurements were performed on samples without previous treatment. The optimised procedure allowed the direct determination of metals at the m g kg-1 level. The performance of the procedure was compared with electrothermal atomic absorption spectrometry and DPASV applied to digested samples, and showed better accuracy. The procedure was applied to the determination of toxic elements in commercial beet sugar samples and levels of metals below 35 m g kg-1 Pb, 80 m g kg-1 Zn and 10 m g kg-1 Cd were found.