title: Natural radionuclides in drinking water supplies of São Paulo State, Brazil and consequent population doses.
abstract: The activity concentrations of 228Ra, 226Ra and 222Rn have been analysed in 452 drinking water supplies of São Paulo State. This study started in 1994 and covered 54% of the 574 existing counties. Concentrations up to 235 and 131 mBq l-1 were observed for 226Ra and 228Ra, respectively, whereas 222Rn concentrations reached 315 Bq l-1. Radiation doses up to 0.3, 0.6 and 3.2 mSv yr-1 were estimated for the critical organs, for the ingestion of 226Ra, 226Ra and 222Rn, respectively. The corresponding committed effective doses reached values of 6 x 10(-3), 2 x 10(-2) and 3 x 10(-1) mSv yr-1, for the same radionuclides. These results indicate that 222Rn makes the highest contribution to the total effective dose.
authors.affiliation: Departamento de Radioprotecão Ambiental, Instituto de Pesquisas Energéticas e Nucleares Travessa R, 400-Cidade Universitária, Caixa Postal 11049-CEP 05422-970, São Paulo, Brazil. jolivei@net.ipen.br
authors.forename: J
authors.initials: J
authors.lastname: de Oliveira
authors.forename: B P
authors.initials: BP
authors.lastname: Mazzilli
authors.forename: M H
authors.initials: MH
authors.lastname: Sampa
authors.forename: E
authors.initials: E
authors.lastname: Bambalas
mesh_terms: D001938:Brazil; D006801:Humans; D011829:Radiation Dosage; D011883:Radium / Q000032:analysis; D011886:Radon / Q000032:analysis*; D014875:Water Pollutants, Radioactive / Q000032:analysis*; D014881:Water Supply / Q000032:analysis*
chemical_list: D014875:Water Pollutants, Radioactive; D011886:Radon; D011883:Radium