Monitoring of radionuclides in soil and bone samples from Austria

Abstract

The activity concentrations of anthropogenic (⁹⁰Sr, ¹³⁷Cs) and natural (²³⁸U, ²³²Th, ⁴⁰K, ²¹⁰Pb) radionuclides were determined in eight soil profiles from three different regions in Austria (Styria, Carinthia and Salzburg). A direct correlation between the activity concentration of ⁹⁰Sr and ¹³⁷Cs in soil samples and site altitude was found. ⁹⁰Sr and ²¹⁰Pb activity concentrations were also determined in bone ash of deer hunted in these regions. Additional bone samples were collected all over Austria. Totally 39 deer bones were investigated for this work, and some values were adopted from our earlier publications to give an overview of samples collected from sites covering a broad range of altitudes. The bone and soil samples were collected in the time period of 2001-2009. The ⁹⁰Sr values in deer bones are directly proportional to the values in the respective soil samples and also to the age of the animals. For the ⁹⁰Sr and ²¹⁰Pb determinations in bone samples first Pb was separated on a Dowex column, then Sr was purified using Sr·Spec® resin. In soil samples an additional hydroxide precipitation was employed to eliminate interfering iron. For the first time also the 3M Empore® Sr Rad disk method was successfully applied to bone samples. With this method the chemical procedure can be shortened by more than a factor of 2. The ⁹⁰Sr and ²¹⁰Pb fractions were measured by liquid scintillation counting, while the chemical yields were determined by ICP-MS. The activity concentrations of ⁴⁰K, ²³⁸U, ²³²Th and ¹³⁷Cs in soil samples were evaluated using gamma-ray spectrometry. The investigation was part of the PhD work of the first author.