Determination of cadmium and lead in vegetables after activated-carbon enrichment by atomic absorption spectrometry

Abstract

An enrichment method has been developed for the determination of cadmium and lead in vegetable matter by flame atomic absorption spectrophotometry after preconcentration with 8-hydroxyquinoline or cupferron on activated-carbon. An enrichment factor of up to 100 was achieved by using both of the mentioned complexing reagents. The optimum lowest pH values were found as 4.8 and 4.4 with cupferron, and 5.3 and 5.8 with oxine, for cadmium and lead, respectively. The effect of decomposition procedures, such as dry and wet ashing, on the recovery were also studied and compared. The relative standard deviations were found to be 2% for cadmium (7 µg l^–1 Cd) and 3% for lead (70 µg l^–1 Pb). Vegetable samples from fertilized farmland and roadside areas of Elaziğ, Turkey were analysed by using the proposed method.