Radioactive characterization of phosphogypsum from Imbituba, Brazil

• Published in: Journal of environmental radioactivity Vol. 126; pp. 188 - 195
• Main Authors: Borges, Renata Coura, Ribeiro, Fernando Carlos Araujo, Lauria, Dejanira da Costa, Bernedo, Alfredo Victor Bellido
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-12-2013; Elsevier
• Subjects: Activation; Agriculture; Analysis methods; Applied sciences; Brazil; Calcium Sulfate - analysis; Calcium Sulfate - chemistry; construction materials; Detectors; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Environmental Monitoring; Environmental Protection Agency; Exact sciences and technology; Gamma spectrometry; germanium; Natural radionuclide; nuclear power; Nuclear reactor components; Phosphogypsum; Phosphorus - analysis; Phosphorus - chemistry; Pollution; Pollution, environment geology; Radioactivity; radionuclides; Radium - analysis; Sampling; sediments; soil; Soil and sediments pollution; Soil Pollutants, Radioactive - analysis; Soils; spectroscopy; Thorium - analysis; Brazil; United States; South America; Brazil, Santa Catarina; USA; Natural radionuclide; Phosphogypsum; Gamma spectrometry; Natural origin pollution; gamma-ray spectroscopy; neutron activation analysis; Natural radioactivity; Radiochemical analysis; radioactive isotopes; Semiconductor detector; Soil pollution; sediments
• ISSN: 0265-931X; 1879-1700
• DOI: 10.1016/j.jenvrad.2013.07.020

This research aims to characterize the content of natural occurring radionuclides in phosphogypsum stacks at Imbituba, Santa Catarina state, Brazil. 226Ra, 228Ra, 40K, 238U and 232Th 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 226Ra 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 226Ra or 228Ra for the use of PG in agriculture as well as building materials.
•Concentration of 238U and 232Th in the PG stack 1 indicated an igneous origin.•The origin of the stack 2 cannot be determined due the similar values.•Concentration of 226Ra is below the limit recommended for use in agriculture.•Distribution of radionuclides through the stacks profile was very heterogeneous.•Low concentrations of 226Ra and 228Ra in soils of the areas surrounding the stacks.