Faculty Collaboration Database

The independent contribution of bone and erythrocyte lead to urinary lead among middle-aged and elderly men: the normative aging study. Environ Health Perspect 1999 May;107(5):391-6

Date

04/22/1999

Pubmed ID

10210695

Pubmed Central ID

PMC1566410

DOI

10.1289/ehp.99107391

Scopus ID

2-s2.0-0032864185 (requires institutional sign-in at Scopus site)   51 Citations

Abstract

Plasma is the component of blood from which lead is free to cross cell membranes and cause organ toxicity. Plasma lead levels, however, are extremely low and difficult to measure. Urinary lead originates from plasma lead that has been filtered at the glomerular level; thus, urinary lead adjusted for glomerular filtration rate serves as a proxy for plasma lead levels. In this investigation we examined the interrelationships of lead levels in whole blood corrected by hematocrit [i.e., erythrocyte lead (EPb)], trabecular bone (TBoPb), cortical bone (CBoPb), and urine excreted over 24 hr (UPb); all samples were obtained from 71 middle-aged and elderly men with no known occupational lead exposures. Lead was measured by graphite furnace atomic absorption spectroscopy (blood), K-X-ray fluorescence (bone), and inductively coupled plasma mass spectroscopy (urine). Lead levels were generally low, with mean EPb, TBoPb, and CBoPb values of 13.8, 31.1, and 21.7 microg/g, respectively, and a median UPb value of 6.15 microg/day. In generalized additive models adjusted for body weight and creatinine clearance rate, both EPb and bone lead variables remained independently and significantly associated with UPb. This finding suggests that bone influences plasma lead in a manner that is independent of the influence of erythrocytic lead on plasma lead. Thus, the superiority of bone lead over blood lead in predicting some chronic forms of toxicity may be mediated through bone's influence on plasma lead. In addition, this study suggests that measurement of urinary lead might be useful as a proxy for plasma lead levels in studies of lead toxicity.

Author List

Tsaih SW, Schwartz J, Lee ML, Amarasiriwardena C, Aro A, Sparrow D, Hu H

Author

Shirng-Wern Tsaih Research Scientist II in the Obstetrics and Gynecology department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Aged
Aged, 80 and over
Aging
Bone and Bones
Erythrocytes
Humans
Lead
Linear Models
Male
Middle Aged
Reference Values