MEASUREMENT OF THE FLUX OF LEAD FROM BONE TO BLOOD IN A NONHUMAN PRIMATE (MACACA-FASCICULARIS) BY SEQUENTIAL ADMINISTRATION OF STABLE LEAD ISOTOPES

To better understand the kinetics of the transfer of lead from bone to blood, we have developed and tested a method in which sequential dose s of lead, each enriched with a different stable isotope, were adminis tered in a nonhuman primate Macaca fascicularis whose skeleton had bee n previously labeled with lead of known isotopic composition. Lead iso topic ratios of blood and bone samples, analyzed by thermal ionization mass spectrometry (TIMS), were unmixed by isotope dilution techniques . The first label administered allows the contribution from historical bone stores to be measured. Subsequent labels allow measurement of bo th the historical bone stores and the previous labels that have become recently incorporated into bone. The method may be extended to studie s of bone lead mobilization in pregnancy, lactation, menopause, or in disease states such as postmenopausal osteoporosis. (C) 1996 Society o f Toxicology