Direct Determination of Lead, Cadmium, Zinc, and Copper in Honey by Electrothermal Atomic Absorption Spectrometry using Hydrogen Peroxide as a Matrix Modifier

Abstract

Electrothermal atomic absorption spectrometric procedures for the rapid determination of copper, zinc, lead, and cadmium in honey are proposed. The samples are dissolved in a medium containing 10% v/v concentrated hydrogen peroxide and 1% v/v concentrated nitric acid and directly introduced in the electrothermal atomizer. In this way, even with no previous mineralization of the samples, organic matter is efficiently destroyed during the heating cycle, thus avoiding the buildup of carbonaceous residues inside the atomizer and permitting low background signals to be obtained. Calibration is carried out using aqueous standards. The metal contents of honey samples of different origin obtained by using the proposed procedures agree with those obtained by means of a lengthy conventional procedure based on a previous mineralization stage. Keywords: Lead; cadmium; zinc; copper; AAS; ETAAS; honey