Determination of lead in wine, other beverages and fruit slurries by flow injection hydride generation atomic absorption spectrometry with on-line microwave digestion

Abstract

A simple and rapid flow injection-lead hydride generation atomic absorption spectrometry (Fl-HG-AAS) method was optimized for the determination of lead in wine, other beverages and fruit. Lead hydride was generated in HNO₃–H₂O₂ medium using NaBH₄ as reducing agent. To determine lead in beer, juice and fruit, a microwave over was coupled on-line to the Fl-HG-AAS system. For fruit, the lead hydride was generated from slurries of the fresh sample. No matrix effect was found in the determination of lead. The method enabled the direct determination of lead in untreated samples with use of an aqueous calibration graph. The detection limit was 10 µg l^–1 in wine and other beverage samples, and 1.0 ng in fruit.