DECORPORATION OF POLONIUM FROM RATS BY NEW CHELATING-AGENTS

The effectiveness of newly synthesised thiol chelating agents has been studied to reduce Po-210 in organs and tissues of rats. From four der ivatives of meso-2,3-dimercaptosuccinic acid (DMSA) only the ethoxyeth yl diester (DEEDMS) was efficient in decreasing total activity in the analysed tissues (to 80% of control animals) when repeated subcutaneou s treatment started 1 h after intravenous injection of Po-210. The mos t pronounced effect was achieved with three derivatives of dithiocarba mate: N,N'-dimethyl-(MeTTC), N,N'-diethyl-(EtTTC), droxyethyl)ethylene diamine-N,N'-bisdithiocarbamate (HOEtTTC). When treatment started imme diately after Po-210 administration, the total content of Po-210 in an alysed tissues was reduced to 74-41% of control values. These bis-dith iocarbamates were further used in combination with 2,3-dimercaptopropa ne-1-sulphonate (DMPS) for removal of intramuscularly injected Po-210, Simulating contaminated wounds. When DMPS was injected locally and di ethyldithiocarbamate (DDTC) derivates repeatedly subcutaneously, the t otal amount of Po-210 retained (including the injection site and inner organs) was reduced by 40-50% of control values.