53. DTPA Treatment for Removal of Inhaled Plutonium Nitrate in Rats.
Satoshi Fukuda and Haruzo Iida
Keywords: plutonium, inhalation, Zn-DTPA, uranium-DTPA compound
This study was performed in order to determine the maximum removal rate of plutonium by DTPA treatment. Aerosols of a complex of plutonium-239 and DTPA (Pu-DTPA) and plutonium nitrate were inhaled by 40 female 3-month-old Wistar rats. Ten rats from the inhaled Pu-DTPA and Pu nitrate group were sacrificed in groups of five at 3 and 7 days. Subsequently, in the period from 7 to 28 days after inhalation, five rats in each group were orally administered Zn-DTPA via their drinking water. The activity of plutonium which was retained in the urine and feces collected at 24 hr-intervals and in all organs was measured. The body retention rates of plutonium in the plutonium-nitrate and plutonium-nitrate + Zn-DTPA groups observed for 28 days were 30.4%, and 23.5%, respectively, of total intake, while those in the Pu-DTPA and Pu-DTPA + Zn-DTPA groups were reduced to 2.3%, and 1.5%, respectively. The administration of Zn-DTPA in the plutonium-nitrate group enhanced the excretion of plutonium in the excreta (Fig. 25), whereas such increases in the Pu-DTPA group were not observed. The greater part of the plutonium retained in the bodies of rats in the plutonium-nitrate group was deposited in the lung. The results indicate that DTPA essentially has the effect of reducing the amount of plutonium in the body, up to about 2% of intake. The problem might be that the effects of DTPA treatment might actually be low if DTPA were administered to persons contaminated with plutonium in an accident. In conclusion, attempts to enhance the effects of DTPA and the development of new chelating agents will be necessary to adequately reduce the risk of plutonium inhalation in the future.
Publications:
Fukuda, S. and Iida, H.: Biomarkers and Environment. 4, Suppl. 1, 66-69, 2001.
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