EVALUATION OF THE EFFICIENCY OF DTPA AND OTHER NEW CHELATING-AGENTS FOR REMOVING NEPTUNIUM FROM TARGET ORGANS

Diethylenetriamine pentaacetic acid (DTPA) has been tested with 8 othe r new chelators for neptunium decorporation after systemic contaminati on in the rat. The ligands were injected intravenously at a dosage of 30 mu mol.kg(-1) and the animals killed 24 h later. The results show t hat none of the chelators tested was efficient in removing significant amounts of the radionuclide from the body. In order to understand why these chelators were ineffective, in vitro approaches have since been developed in which high concentrations of DTPA were added to Np-beari ng ligands in the blood, liver and skeleton. The main conclusions were that under our experimental conditions neptunium was not chelatable a fter its organ deposition.