%0 Journal Article
%T Uranium isotopes in groundwater occurring at Amazonas State, Brazil
%A Silva, M. L. da
%A Bonotto, D. M.
%J Applied Radiation and Isotopes
%D 2015
%V 97
%@ 0969-8043
%F Silva+Bonotto2015
%O exported from refbase (http://www.uhydro.de/base/show.php?record=140), last updated on Fri, 26 Jan 2024 13:19:04 +0100
%X This paper reports the behavior of the dissolved U-isotopes 238U and 234U in groundwater providing from 15 cities in Amazonas State, Brazil. The isotope dilution technique accompanied by alpha spectrometry were utilized for acquiring the U content and 234U/238U activity ratio (AR) data, 0.01–1.4µgL−1 and 1.0–3.5, respectively. These results suggest that the water is circulating in a reducing environment and leaching strata containing minerals with low uranium concentration. A tendency to increasing ARs values following the groundwater flow direction is identified in Manaus city. The AR also increases according to the SW–NE directions: Uarini→Tefé; Manacapuru→Manaus; Presidente Figueiredo→São Sebastião do Uatumã; and Boa Vista do Ramos→Parintins. Such trends are possibly related to several factors, among them the increasing acid character of the waters. The waters analyzed are used for human consumption and the highest dissolved U content is much lower than the maximum established by the World Health Organization. Therefore, in view of this radiological parameter they can be used for drinking purposes.
%K Amazon area
%K Dissolved uranium
%K Groundwater
%K Tube wells
%K U/U activity ratio
%U https://www.sciencedirect.com/science/article/pii/S096980431400431X
%P 24-33