Determination of cadmium and lead in fresh meat by slurry sampling graphite furnace atomic absorption spectrometry

Abstract

In this work a method for cadmium and lead determination in fresh meat based on slurry sampling graphite furnace atomic absorption spectrometry is proposed. The fresh meat samples were weighed directly into the autosampler cups of the spectrometer using a microbalance and the slurry was prepared using tetramethylammonium hydroxide (TMAH). The use of the response surface method for optimizing the slurry preparation has shown that it was possible to find the optimum zone in the experimental field of the variables under study. Calibration was performed against aqueous standards and a mixture of 0.05% v/v Pd + 0.03% v/v Mg + 0.05% v/v Triton X-100 was used as a modifier. The results obtained for cadmium and lead in two certified reference materials were statistically not different from the certified values on a 95% confidence level, indicating that calibration against aqueous standards is suitable for this application. A comparison of the results obtained by slurry sampling with the digestion method adopted by the Brazilian Ministry of Agriculture showed no significant differences between the results at the 95% confidence level. The positive results obtained in this work suggest that the application of this procedure in other element determinations is worthy of exploration.