Determination of cadmium in calcium chloride extracts of soils by atom-trapping atomic absorption spectrometry

Abstract

A method is described for the determination of cadmium in 0.05 M calcium chloride extracts of soils by atom-trapping atomic absorption spectrometry (ATAAS). The technique of ATAAS has been applied to such determinations of cadmium as the levels encountered are too low for detection by conventional flame atomic absorption methods. Examination of the effects of major elements present in the extracts on the cadmium response demonstrates that this method is relatively free from interference problems. A comparison of the results obtained with those determined by a separation procedure using a chloroform extract of the dithizonate with back-extraction into HCl and conventional atomic absorption spectrometry has been made. The method has been used for the determination of cadmium in a number of Scottish topsoils.