| A Human In Vivo Model for the Determination of Lead Bioavailability Using Stable Isotope Dilution Joseph H. Graziano,1,2 Conrad B. Blum,3 Nancy J. LoIacono,1,2 Vesna Slavkovich,1,2 W. I. Manton,4 Susan Pond,5 and Michael R. Moore6
1Department of Pharmacology, 2Division of Environmental Health Sciences, School of Public Health, and 3Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY 10032 USA; 4Mass Spectrometry Laboratory, University of Texas at Dallas, Richardson, TX 75080 USA; 5Department of Clinical Pharmacology and 6National Research Centre for Environmental Toxicology, University of Queensland, Brisbane, Australia Abstract Beverages stored in lead-crystal glass accumulate extraordinary concentrations of lead. We obtained a lead-crystal decanter manufactured with lead from Australia, where the ratio of 206Pb/207Pb is distinctly different from that in the United States. We sought to determine the bioavailability of crystal-derived lead, using the technique of stable isotope dilution in blood. We conducted a single-dose, nonrandomized cross-over study in which participants were admitted to the Clinical Research Center twice, 1 week apart. During the first admission, subjects ingested sherry obtained from the original bottle. During the second admission, they ingested sherry that had been stored in the crystal decanter and that had achieved a lead concentration of 14.2 mol/l. After ingesting decanter-stored sherry, mean blood lead rose significantly (p = 0.0003) from 0.10 to 0.18 mol/l, while mean 206Pb/207Pb fell from 1.202 to 1.137 (p = 0.0001) . On average, 70% of the ingested dose of lead was absorbed. We conclude that lead derived from crystal glass is highly bioavailable ; repeated ingestions could cause elevated blood lead concentration. The technique of stable isotope dilution lends itself to the study of the bioavailability of lead in other matrices, including soil. Key words: alcohol, bioavailability, lead, lead isotopes, mass spectrometry, stable isotope dilution. Environ Health Perspect 104:176-179 (1996) Address correspondence to J. H. Graziano, Division of Environmental Health Sciences, Columbia University School of Public Health, 60 Haven Avenue, B-1, New York, NY 10032 USA. We gratefully acknowledge the expert nursing staff and the nutrition unit of the Irving Center for Clinical Research. This work was supported in part by grants ES 06101, ES 03460, EPA CR822793, RR 00645, and the Lucille P. Markey Program in Molecular Toxicology and Nutrition. Received 25 July 1995 ; accepted 23 October 1995. The full version of this article is available for free in HTML format. |