Direct determination of copper, lead and cadmium in aniseed spirits by electrothermal atomic absorption spectrometry

Direct determination of copper, lead and cadmium by electrothermal atomic absorption spectrometry in aniseed spirits was proposed. The methods were validated by studying quality parameters such as trueness, precision, linearity and sensitivity. Recoveries ranging between 96% and 104% were obtained from spiked samples at several concentration levels. Repeatability was less than 5% and intermediate precision was less than 8%. The procedure is fast and shows limits of detection of 0.6, 0.7 and 0.04 μg l−1 for Cu, Pb and Cd, respectively. Samples were just diluted in a water/ethanol/nitric acid mixture. Cu was present at higher concentrations, with values in the range 6–473 μg l−1. Minor levels of Pb and Cd were present with concentrations of less than 6 and 1.4 μg l−1, respectively.