Statistical studies of matrix effects on the determination of cadmium and lead in fertilizer materials and plant tissue by flameless atomic absorption spectrometry

Abstract

The evaluation of interferences on an individual basis can give unreliable information, whereas a statistical approach shows the synergic effects of different ions and gives more reliable information with fewer determinations. Cadmium and lead in phosphate rock, wet-process phosphoric acid, and plant tissue can be determined directly after a nitric acid dissolution by carbon-rod atomization with no significant interference within the range studied. The results are in good agreement with results obtained by flame analysis when a careful control of acid concentration is maintained between samples and standards. Results on materials of low cadmium content are more reliable by carbon-rod atomization.