ACCURATE DETERMINATION OF LEAD IN WINES BY INDUCTIVELY-COUPLED PLASMA-MASS SPECTROMETRY

The capability of inductively coupled plasma mass spectrometry (ICP-MS ) for Pb determinations in wine samples is studied. An evaluation is m ade of the signal behaviour in aqueous ethanolic medium. The effect of preliminary sample preparation on signal suppression or enhancement i s investigated in conjunction with the ability of internal standardiza tion to correct for it. As a result, an accurate and precise method of analysis is described in which the sample preparation is limited to a 10-fold dilution and external calibration is applied for quantitation . A detection limit of 0.2 mug l-1 Pb in wine is achieved. The Pb cont ent of ten different wines was found to range around 40 mug l-1 with e xtreme values of 1.63 and 58.8 mug l-1.