Mobilization, redistribution and bioavailability of potentially toxic elements in Shidiya phosphorites, Southeast Jordan

Shidiya Phosphorites, Southeast Jordan, provide a typical example of natural geological materials depleted with potentially toxic elements as compared to other phosphate deposits from all over the World. Nevertheless, the environmental concern as to whether processing and fertilizer production might affect the potentially toxic element concentrations in these phosphates positively or negatively has to be avoided. In order to do so, this study was designed to provide information on the redistribution pathways of the measured toxic elements during the several processing steps, including crushing, screening, washing, flotation and drying processes. It aimed also at providing information on the redistribution pathways during the different phosphate fertilizer production steps. The bioavailability of potentially toxic elements in acidic and alkaline environments has also been assessed.