Transfer of polonium, neptunium, plutonium and americium to the primate fetus
F. Paquet, J.-L. Poncy, G.J. Ham, S.L. Prosser and J.D. Harrison
Radiat. Prot. Dosim. 1998, 79(1-4), pp 303-306
WORKSHOP ON INTAKES OF RADIONUCLIDES: Occupational and Public Exposure - Proceedings of a Workshop held in Avignon, France. September 15-18 1997
Two baboons in the fifth month of pregnancy were given a single intravenous injection of a mixture of 210Po, 237Np, 239Pu and 241Am in citrate solution. Total retention in each fetus, measured at one week after injection, accounted for about 1% of administered 210Po and 237Np, 4% of 239Pu and 0.4% of 241Am. These values correspond to fetal:maternal whole-body concentration ratios, CF:CM, of about 0.3 for 210Po, 0.6 for 237Np, 1.3 for 239Pu and 0.1 for 241Am. Retention in the placenta varied from about 1% of administered 237Np to 8-12% of 239Pu. Available data for other species, including rats and guinea pigs, generally show lower levels of retention in the fetus and placenta, particularly for 239Pu. It is proposed that estimates of dose to the human fetus from intakes during the third trimester of pregnancy should be based directly on the baboon data.