Solvent extraction and sensitive one-drop flame atomic absorption spectrometric determination of leachable lead from lead-glazed ceramicware.

Abstract

Low concentrations of lead leached from lead-glazed ceramicware into 4% acetic acid were determined by the one-drop atomic absorption spectrometry with a fuel-lean air-acetylene flame after the extraction of lead pyrrolidin-l-yldithioformate into chloroform. To a glass test tube with a stopper, 5 ml (or 10 ml) of 4% acetic acid leachate and 1 ml (or 2 ml) of 1% ammonium pyrrolidinedithiocarbamate solution were taken and the mixture was shaken with 0.5 ml of chloroform 3 times for 10 s by hand. Direct nebulization of 50 μl of the chloroform extract of lead complex gave a 3.9 times more sensitive signal height than that obtained by nebulizing a 4% acetic acid solution. With this technique, lead at 0.1 μg/ml levels in 4% acetic acid was easily determined without background correction. This method was very simple and gave very good reproducibility (RSD=1.4% at 3 μg/ml chloroform).