Determination of rare earths elements and others in Cuban soils

The determination of heavy metals in some components of the agricultural production such as soils, natural or commercial fertilizers, vegetables, etc.. provides valuable data for studying possible mechanisms of dietary intoxication. The later could be related with certain diseases the Neuropathy appeared in Cuba on late 1992. The main objective of the present study was the elaboration of a procedure for the determinantion of Y, La, Ce, Pr and Nd in soils by Spectrophotometry with Arsenazo III preceded by a separation-concentration stage, which includes successive process of coprecipitation and ionic exchange. Simultaneouly multielement analysis by Energy Dispersive X Ray Fluorescence (including Y, La, Ce and Nd) and Flame Atomic Absorption Spectrophotometry was carried out in order to obtain a general characterization of the samples. The reliability of the developed analytical porocedures is reported. The accuracy of the methods was evaluated by the use of certificate reference materials and the statistical intercomparison of the obtained results. The precision was examined by analyzing replicate samples. (author). 22 refs., 4 figs., 5 tabs