Treatment of human contamination with plutonium and americium: would orally administered Ca- or Zn-DTPA be effective?
Accidental or deliberate dispersion of plutonium (Pu) and americium (Am) into the public environment could contaminate large numbers of people by inhalation. If measures to reduce the internal dose are considered appropriate, oral administration of either calcium (Ca) or zinc (Zn) diethylenetriaminepenta-acetic acid (DTPA) would be the simplest treatment. Published experimental data from rats on the effects of oral DTPA on the retention of inhaled Pu and Am show that: (1) orally administered Zn-DTPA is as effective as repeated intravenous injection for the decorporation of Pu and Am inhaled as nitrates, although higher dosages are required; (2) oral Zn-DTPA appears to be an effective treatment for Am dioxide but not Pu dioxide; (3) maximum decorporation of Pu, by oral or intravenous administration, requires a large molar excess of Zn-DTPA over Pu (>1 x 10(6)); (4) neither oral nor injected Zn-DTPA are likely to be effective for Pu oxides, nor when Pu and Am nitrates are mixed with other dusts. It is concluded that oral administration of a simple aqueous solution of Zn-DTPA could be an important treatment in accident or emergency scenarios after intake of pure chemical forms of Pu and Am, which are highly or moderately soluble in biological fluids. However, more research is needed on the efficacy of treatment when these forms are mixed with other materials. Importantly, studies designed to increase the efficiency of uptake of DTPA from the gastrointestinal tract could appreciably reduce the dosage.
Taylor
David M
DM
School of Chemistry, Cardiff University, Cardiff CF10 3TB, UK. davtay@btinternet.com
Hodgson
Susan A
SA
Stradling
Neil
N
D000284:Administration, Oral; D000576:Americium / Q000506:poisoning*; D001681:Biological Assay / Q000379:methods*; D001822:Body Burden; D002614:Chelating Agents / Q000008:administration & dosage; D003198:Computer Simulation; D006801:Humans; D008954:Models, Biological; D004369:Pentetic Acid / Q000008:administration & dosage*; D011005:Plutonium / Q000506:poisoning*; D011829:Radiation Dosage; D011832:Radiation Injuries / Q000209:etiology / Q000517:prevention & control*; D011837:Radiation-Protective Agents / Q000008:administration & dosage; D011874:Radiometry / Q000379:methods; D012062:Relative Biological Effectiveness; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D002614:Chelating Agents; D011837:Radiation-Protective Agents; D011005:Plutonium; D004369:Pentetic Acid; D000576:Americium