Evaluation on rare earth elements of Brazilian agricultural supplies

This work focuses on the determination of rare earth elements (REE) in Brazilian agricultural supplies by instrumental neutron activation analysis (INAA). The results obtained have shown that La, Ce, Nd, Sm, Eu, Tb, Yb, Lu and Sc are present within a large range of mass fractions in the agricultural supplies analysed. The thermophosphate and single superphosphate showed the highest mass fractions of REE. Considering the recommended dose and long-term use, NPK fertilizers, single superphosphate and thermophosphate can significantly increase the content of REE in soil and may cause harmful effects to environment and humans.   Key words: Agricultural supplies, rare earth elements, lanthanoids, phosphate fertilizer, INAA.