Optimized microwave digestion procedure for cadmium analysis of mussel samples

Abstract
A simple and rapid acid sample digestion method by microwave heating in high pressure teflon bombs is reported for the determination of cadmium in mussels by flame atomic absorption spectrometry (FAAS) coupled on-line with a flow-injection preconcentration system. Tests concerning the digestion time, the power of the microwaves and the amount of nitric acid were studied with the National Research Council of Canada lobster hepatopancreas marine (Tort-1) as certified reference material. Using 2 min of digestion time and 2 mL of nitric acid, the complete dissolution of 0.2 g of freeze dried sample is possible. The analytical results, obtained with calibration graph as well as by the standard addition method, were agreed well with the certified value of the reference material. This procedure was applied to the determination of cadmium in mussel samples from estuaries in Galicia, Spain.