The Plutonium Content of Human Fetal Tissue and Implications for Fetal Dose

Abstract

Measurements have been made of plutonium concentrations in human fetal tissues received from second trimester terminations carried out in west Cumbria and Oxfordshire, using standard chemical techniques and alpha or mass spectrometry. Fetal tissue concentrations of a few tens of µBq.kg-1 were measured; placental concentrations were of the same order of magnitude. These concentrations have been compared with an estimated average maternal concentration of 0.3 mBq.kg-1, indicating no concentration of this element in the fetus, relative to the mother. The measured plutonium concentrations have also been compared with those of naturally occurring radionuclides, in particular 210Po, determined by other workers at NRPB in a complementary study. The implication of these measured plutonium concentrations for radiation dose, is that exposure of the human fetus to environmental levels of plutonium results in an equivalent dose to the fetus during pregnancy of less than 0.02 µSv. In addition, the risk of detriment from plutonium is considerably lower than for the naturally occurring radionuclide 210Po.