Radioactive characterization of phosphogypsum from Imbituba, Brazil.

This research aims to characterize the content of natural occurring radionuclides in phosphogypsum stacks at Imbituba, Santa Catarina state, Brazil. (226)Ra, (228)Ra, (40)K, (238)U and (232)Th were determined in PG, soils and sediment samples by gamma spectrometry using the hyper pure germanium detector and neutron activation. The migration of radionuclides in the phosphogypsum profile did not show the same behavior for all sampling sites. The mean activity concentration of (226)Ra was 95 Bq kg(-1), which is far below the limit recommended by the U.S. Environmental Agency (USEPA) for its application in agriculture (370 Bq kg(-1)) and the Brazilian Commission of Nuclear Energy Resolution 113 that established a reference level of 1000 Bq kg(-1) of (226)Ra or (228)Ra for the use of PG in agriculture as well as building materials.