Application and methodology of in vivo K x-ray fluorescence of Pb in bone (impact of KXRF data in the epidemiology of lead toxicity, and consistency of the data generated by updated systems)

Abstract

K x-ray fluorescence (KXRF) technology has been used to make in vivo measurements of lead in bone for more than three decades. The data obtained are beneficial to research on lead toxicity as well as, in certain circumstances, the practice of occupational and environmental medicine. This paper reviews the impact of KXRF data on epidemiologic research involving lead toxicity and demonstrates that bone lead is and will continue to be a valuable biomarker in addressing long-term health effects related to cumulative exposure. The KXRF system has been improved and upgraded several times ever since it was first used. The consistency of the data obtained from these KXRF systems has been investigated in many studies. This paper provides an overview of the factors that will affect the data generated by the KXRF systems. A calibration problem encountered in one of the major KXRF laboratories is described, and the approach taken to solve the problem is discussed. Despite all the theoretical considerations, there are still some important practical challenges to the intercalibration of KXRF instruments both within the laboratory, and between laboratories. Copyright © 2007 John Wiley & Sons, Ltd.