Hydride Generation-Nondisperion Atomic Fluorescence Spectrometric Determination of Trace Amounts of Lead in Milk and Dairy Products

Atomic fluorescence spectrometry with intermittent flow injection-hydride generation technique was applied to the determination of trace amounts of lead in milk and dairy products. Samples were pretreated by the dry ashing method and the ignited residues were taken up with dil. HCl. Blank value and detection limit of the determination were lowered and improved by treating the potassium ferricyanide used in the hydride generation with acid-washed active carbon. Amounts of co-existing ions in samples of milk and dairy products were found to be lower than the tolerance limits tested. Detection limit (3S) was found to be 0.22 μg·L-1. Tests for precision,expressed as RSD′s (n=6) and recovery on 3 different concentration levels,and values obtained were in the ranges 0.5%-3.7% and 92.5%-105.0% respectively.