Partitioning and Redistribution of Exogenous Ra Sup 226 in Farm Soils from the Vicinity of the First Brazilian Mine and Mill

摘要

A sequential selective extration method was employed to assess the partitioning and redistribution of exogenous sup 226 Ra into geochemical fractions of farm soils collected around the first Brazilian Uranium Mine and Mill. Six soil samples were contaminated in the laboratory by (sup 226)Ra solution, simulating an irrigation procedure. After selective extractions, (sup 226)Ra was analysed in six geochemical fractions: soluble (A); exchangeable (E); bound to carbonates (C); reducible (R); oxidizable (O); residual or matricial (M). The same method was also used in these soils before and after cultivation. The exogenous (sup 226)Ra was mainly associated to the (R) and (O) fractions followed by the (E) and (C) ones. Exchangeable (sup 226)Ra (fractions (A) + (E)) represents 21.8%. Statistically significant differences before and after cultivation were obtained only in the fractions (C) and. (Atomindex citation 19:044421)