Distribution of U and Th decay series and rare earth elements in sediments of Santos Basin:: Correlation with industrial activities

Santos Basin, located in Southwest Brazil, is considered the most important industrial region of the country. Among the industrial activities present, phosphate fertilizer plants are responsible for the production of 69 million tons of phosphogypsum waste, which is stockpiled in the surrounding environment. This waste concentrates radionuclides of the natural series as well as rare earth elements originally present in the phosphate rock used as raw material. This study aims to evaluate the environmental impact of such activities in the sediments of the estuarine system by measuring the concentration of U, Th and rare earth elements and activity concentration of radionuclides (226)Ra, (228)Ra, (228)Th and (210)Pb.