title: Doses from 222Rn, 226Ra, and 228Ra in groundwater from Guarani aquifer, South America.
abstract: Groundwater samples were analysed for 222Rn, 226Ra, and 228Ra in Guarani aquifer spreading around 1 million km2 within four countries in South America, and it was found that their activity concentrations are lognormally distributed. Population-weighted average activity concentration for these radionuclides allowed to estimate a value either slightly higher (0.13 mSv/year) than 0.1 mSv for the total effective dose or two times higher (0.21 mSv/year) than this limit, depending on the choice of the dose conversion factor. Such calculation adds useful information for the appropriate management of this transboundary aquifer that is socially and economically very important to about 15 million inhabitants living in Brazil, Argentina, Uruguay and Paraguay.
authors.affiliation: Departamento de Petrologia e Metalogenia, Instituto de Geociencias e Ciencias Exatas, Universidade Estadual Paulista (UNESP), Av. 24-A, No. 1515, C.P. 178, CEP 13506-900, Rio Claro, São Paulo, Brazil. dbonotto@rc.unesp.br
authors.forename: D M
authors.initials: DM
authors.lastname: Bonotto
mesh_terms: D006207:Half-Life; D011883:Radium / Q000032:analysis*; D011886:Radon / Q000032:analysis*; D018570:Risk Assessment; D013020:South America; D014875:Water Pollutants, Radioactive / Q000032:analysis*; D014881:Water Supply
chemical_list: D014875:Water Pollutants, Radioactive; D011886:Radon; D011883:Radium