Accurate analysis of stable isotopes 68Zn, 70Zn, and 58Fe in human feces with neutron activation analysis

Accurate isotopic analysis of human fecal samples is discussed in relation to mineral bioavailability studies of human subjects. It is shown that for bioavailability investigations of Zn and Fe, the method of neutron activation analysis is suitable for routine application to clinical experiments; and the human fecal samples resulting from diet suitably enriched in isotopes 70Zn and 58Fe can be routinely analyzed with relative precisions of about 1% for the isotopes 68Zn, 70Zn and 58Fe.