Distribution of radiocesium and natural gamma emitters in pine needles in coniferious forest sites of Izmir

Using a high-resolution gamma-spectrometer system, the activity concentrations of ⁷Be, ¹³⁷Cs, ⁴⁰K and ²²⁶Ra were determined in the pine needles. Activity concentrations of the concerned radionuclides in the needle samples were as follows: ⁷Be, 24.6±2.40 to 210±7.21 Bq kg⁻¹, ⁴⁰K, 23.5±12.4 to 287±15.6 Bq kg⁻¹, ²²⁶Ra, 0.44±0.12 to 12.3±2.18 Bq kg⁻¹, and ¹³⁷Cs, 0.61±0.30 to 2.29±0.38 Bq kg⁻¹. It is found that the frequency distributions obtained for ⁷Be and ¹³⁷Cs can be fitted to a normal distribution, and for ⁴⁰K and ²²⁶Ra can be fitted to a log-normal distribution.     

In Vitro Binding of Radiocesium to Prussian Blue Coated Strips and Prussian Blue Containing Hemoperfusion Columns as a Potential Tool for the Treatment of Persons Internally Contaminated with Radiocesium

Abstract: Cellulose or nylon strips coated with three different Prussian Blue salts were prepared with cellulose nitrate as binding material. These strips were evaluated for their usefulness for the development of an extracor-poral clearance device for radiocesium, a radionuclide often released after accidents in nuclear installations (for example in Chernobyl). Extracorporeal clearance can be used to enhance the elimination of radiocesium from internally contaminated persons. The stability of these strips and their binding characteristics for radiocesium were investigated. In all studies strips coated with Fe₄[Fe(CN)₆]₃ proved to be the most suitable for further development of an extracorporal clearance device: the strips are stable, have a high binding capacity for radiocesium, and can be sterilized. On the basis of these results, hemoperfusion columns containing Fe₄[Fe(CN)₆]₃-coated strips were developed and tested. In in vitro experiments these columns proved to be successful in removing radiocesium from a pasteurized plasma solution (clearance was ˜ 100 ml/min). The binding capacity of these columns is relatively high. In 4 h the columns are able to bind ˜0.3 TBq of radiocesium. They are a promising development for the enhancement of the removal of radiocesium from the human body. They can also be used for the decontamination of other fluids of chemical or biological origin. Further research is, however, still necessary.     

核应急中去除放射性铯的研究进展

核事故会造成大量的放射性铯泄漏,威胁环境与人类健康安全。因此,对进入环境及人体内的放射性铯离子的去除具有十分重要的意义。本文对核应急中放射性铯离子去除的研究进展进行了综述。目前针对环境土壤中放射性铯离子的污染主要采用直接移除表层部分,并对土壤进行净化处理,涉及的方法包括土壤淋洗法、电动力学修复法以及土壤固载法。对环境水体中放射性铯离子的去除主要采用吸附法,所用吸附剂主要有冠醚、杯芳烃、磷钼酸铵以及普鲁士蓝等。而人体中放射性铯离子的去除主要依靠普鲁士蓝口服促排药物,需要及时多次给药且见效慢,同时仍存在一些严重的不良反应,如易引起低钾血症和消化道不适。因此研究新型的核应急放射性铯离子去除药物,仍具有重要的战略意义。