Decorporation of Polonium from Rats by New Chelating Agents

Abstract

The effectiveness of newly synthesised thiol chelating agents has been studied to reduce 210Po in organs and tissues of rats. From four derivatives of meso-2,3-dimercaptosuccinic acid (DMSA) only the ethoxyethyl diester (DEEDMS) was efficient in decreasing total activity in the analysed tissues (to 80% of control animals) when repeated subcutaneous treatment started 1 h after intravenous injection of 210Po. The most pronounced effect was achieved with three derivatives of dithiocarbamate: N,N'-dimethyl-(MeTTC), N,N'-diethyl-(EtTTC), N,N'-di(2-hydroxyethyl)ethylenediamine-N,N'-bisdithiocarbamate (HOEtTTC). When treatment started immediately after 210Po administration, the total content of 210Po in analysed tissues was reduced to 74-41% of control values. These bis-dithiocarbamates were further used in combination with 2,3-dimercaptopropane-1-sulphonate (DMPS) for removal of intramuscularly injected 210Po, simulating contaminated wounds. When DMPS was injected locally and diethyldithiocarbamate (DDTC) derivates repeatedly subcutaneously, the total amount of 210Po retained (including the injection site and inner organs) was reduced by 40-50% of control values.