A cloverleaf detector system for in vivo bone lead measurement

Abstract

A 4 x 500 mm2 "cloverleaf" low energy germanium detector array has been assembled for the purpose of in vivo bone lead measurement through x-ray fluorescence. Using 109Cd as an exciting source, results are reported from a leg phantom simulating measurement of lead in a human tibia. For high activity (4.0-4.4 GBq) and low activity (0.18-0.19 GBq) sources, measurement results are reported for both the cloverleaf system and a conventional single detector system of equivalent surface area (2000 mm2). The mean uncertainty and reproducibility of measurement were both significantly improved for the cloverleaf system with a high activity 109Cd source. When using a source activity of 4.4 GBq, measurement of the phantom resulted in an average bone lead uncertainty of 0.79 microg/g and a reproducibility of 0.84 microg/g. These results represent the highest precision yet reported from a bone lead x-ray fluorescence system.

Bone manganese as a biomarker of manganese exposure: A feasibility study

“…Some of these in vivo measurement techniques are very well established, such as the measurement of bone lead concentrations [Kondrashov and Rothenberg, 2001;Nie et al, 2006;Fleming and Mills, 2007] and liver and kidney cadmium concentrations [Christoffersson and Mattson, 1983;McNeill and Chettle, 1998]. …”

“…In vivo elemental analysis is an analytical approach where instead of collecting a sample from a person for in vitro analysis, the stored quantity of the element is determined in vivo, non-invasively and without pain or other traditional risks (e.g., infection) to the patient. Some of these in vivo measurement techniques are very well established, such as the measurement of bone lead concentrations [Kondrashov and Rothenberg, 2001;Nie et al, 2006;Fleming and Mills, 2007] and liver and kidney cadmium concentrations [Christoffersson and Mattson, 1983;McNeill and Chettle, 1998].…”

Bone lead (Pb) content at the tibia is associated with thinner distal tibia cortices and lower volumetric bone density in postmenopausal women

“…Bone lead can be measured non-invasively using 109 Cadmium (Cd) X-ray fluorescence (XRF) at sites where soft tissue is minimal, such as the anterior aspect of the mid-tibia, calcaneus, and patella [15]. Lead detection by XRF operates on the principle that lead atoms absorb incident photons of a given energy from the radioactive 109 Cd source and emit a characteristic lower energy, specific to the lead atom.…”

A miniature X‐ray tube approach to measuring lead in bone using L‐XRF

“…The result is a robust measure that accurately reflects bulk bone lead. Recent improvements6 have further secured K‐XRF as the dominant means of assessing cumulative lead exposure through in vivo bone analysis.…”