Advanced

In vivo measurements of lead in fingerbone in active and retired lead smelters

Börjesson, J. LU ; Gerhardsson, L. LU ; Schütz, A. LU ; Mattsson, S. LU ; Skerfving, S. LU and Österberg, K. LU (1997) In International Archives of Occupational and Environmental Health 69(2). p.97-105
Abstract

Object. The aim of this study was to determine the bone lead concentration in lead smelters and reference subjects, relate them to the lead concentration in blood (B-Pb) and urine (U-Pb), and to use the measured bone lead to calculate a biological half-life for lead in bone. Method and design. The lead concentration in the second phalanx of the left index finger (bone-Pb) was determined in vivo using an X-ray fluorescence technique. The study population comprised 89 smelters with a history of long-term exposure to lead (71 active and 18 retired) and 35 reference subjects (27 active and 8 retired) with no known occupational exposure to lead. Bone-Pb was related to the previous lead exposure, estimated as a time-integrated B-Pb (CBLI).... (More)

Object. The aim of this study was to determine the bone lead concentration in lead smelters and reference subjects, relate them to the lead concentration in blood (B-Pb) and urine (U-Pb), and to use the measured bone lead to calculate a biological half-life for lead in bone. Method and design. The lead concentration in the second phalanx of the left index finger (bone-Pb) was determined in vivo using an X-ray fluorescence technique. The study population comprised 89 smelters with a history of long-term exposure to lead (71 active and 18 retired) and 35 reference subjects (27 active and 8 retired) with no known occupational exposure to lead. Bone-Pb was related to the previous lead exposure, estimated as a time-integrated B-Pb (CBLI). Results. The retired smelters had the highest bone-Pb (median value 55 μg/g wet weight, as against 23 μg/g in active smelters) and 3 μg/g in the reference subjects. A strong positive correlation was observed between the bone-Pb and the CBLI among both active (r(s) = 0.73; P < 0.001) and retired (r(s) = 0.71; P = 0.001) smelters. The corresponding correlations between the bone-Pb and the period of employment were of the same magnitude. For retired workers, there were positive correlations between the bone-Pb and the B-Pb (r(s) = 0.58; P = 0.011) and U-Pb (r(s) = 0.56; P = 0.02). Multiple regression analyses showed that bone-Pb was best described by the CBLI, which explained 29% of the observed variance (multiple r2) in bone-Pb in active workers and about 39% in retired workers. The estimated biological half-life of bone-Pba among active lead workers was 5.2 years (95% confidence interval 3.3-13.0 years). Conclusions. The high bone-Pb seen in retired workers can be explained by the long exposure periods, the higher exposure levels in earlier decades, and the slow excretion of lead accumulated in bone. The importance of the skeletal lead pool as an endogenous source of lead exposure in retired smelters was indicated by the associations between the B-Pb or U-Pb, on the one hand, and the bone-Pb, on the other. In active workers, the ongoing occupational exposure was dominant. The in vivo X-ray fluorescence technique is still mainly a research tool, and more work has to be done before it can be used more widely in clinical practice. However, over the next decade we can anticipate retrospective, prospective and cross-sectional epidemiological studies in which bone lead determinations reflecting the previous lead exposure in both occupationally and nonoccupationally lead exposed populations are related to various types of adverse health outcomes. Such studies will improve our knowledge of dose-response patterns and provide data that will have an impact on hygienic threshold limit values and prevention of lead-induced diseases.

(Less)
Please use this url to cite or link to this publication:
author
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Biological half-life, Bone, Lead, Smelter, X-ray fluorescence
in
International Archives of Occupational and Environmental Health
volume
69
issue
2
pages
97 - 105
publisher
Springer
external identifiers
  • scopus:0031060040
ISSN
0340-0131
DOI
10.1007/s004200050122
language
English
LU publication?
no
id
a9a646fd-2d79-44e4-9bd6-607655897c4e
date added to LUP
2018-11-18 13:52:33
date last changed
2019-03-12 04:18:04
@article{a9a646fd-2d79-44e4-9bd6-607655897c4e,
  abstract     = {<p>Object. The aim of this study was to determine the bone lead concentration in lead smelters and reference subjects, relate them to the lead concentration in blood (B-Pb) and urine (U-Pb), and to use the measured bone lead to calculate a biological half-life for lead in bone. Method and design. The lead concentration in the second phalanx of the left index finger (bone-Pb) was determined in vivo using an X-ray fluorescence technique. The study population comprised 89 smelters with a history of long-term exposure to lead (71 active and 18 retired) and 35 reference subjects (27 active and 8 retired) with no known occupational exposure to lead. Bone-Pb was related to the previous lead exposure, estimated as a time-integrated B-Pb (CBLI). Results. The retired smelters had the highest bone-Pb (median value 55 μg/g wet weight, as against 23 μg/g in active smelters) and 3 μg/g in the reference subjects. A strong positive correlation was observed between the bone-Pb and the CBLI among both active (r(s) = 0.73; P &lt; 0.001) and retired (r(s) = 0.71; P = 0.001) smelters. The corresponding correlations between the bone-Pb and the period of employment were of the same magnitude. For retired workers, there were positive correlations between the bone-Pb and the B-Pb (r(s) = 0.58; P = 0.011) and U-Pb (r(s) = 0.56; P = 0.02). Multiple regression analyses showed that bone-Pb was best described by the CBLI, which explained 29% of the observed variance (multiple r<sup>2</sup>) in bone-Pb in active workers and about 39% in retired workers. The estimated biological half-life of bone-Pba among active lead workers was 5.2 years (95% confidence interval 3.3-13.0 years). Conclusions. The high bone-Pb seen in retired workers can be explained by the long exposure periods, the higher exposure levels in earlier decades, and the slow excretion of lead accumulated in bone. The importance of the skeletal lead pool as an endogenous source of lead exposure in retired smelters was indicated by the associations between the B-Pb or U-Pb, on the one hand, and the bone-Pb, on the other. In active workers, the ongoing occupational exposure was dominant. The in vivo X-ray fluorescence technique is still mainly a research tool, and more work has to be done before it can be used more widely in clinical practice. However, over the next decade we can anticipate retrospective, prospective and cross-sectional epidemiological studies in which bone lead determinations reflecting the previous lead exposure in both occupationally and nonoccupationally lead exposed populations are related to various types of adverse health outcomes. Such studies will improve our knowledge of dose-response patterns and provide data that will have an impact on hygienic threshold limit values and prevention of lead-induced diseases.</p>},
  author       = {Börjesson, J. and Gerhardsson, L. and Schütz, A. and Mattsson, S. and Skerfving, S. and Österberg, K.},
  issn         = {0340-0131},
  keyword      = {Biological half-life,Bone,Lead,Smelter,X-ray fluorescence},
  language     = {eng},
  month        = {01},
  number       = {2},
  pages        = {97--105},
  publisher    = {Springer},
  series       = {International Archives of Occupational and Environmental Health},
  title        = {In vivo measurements of lead in fingerbone in active and retired lead smelters},
  url          = {http://dx.doi.org/10.1007/s004200050122},
  volume       = {69},
  year         = {1997},
}