Lead in finger‐bone analysed in vivo in active and retired lead workers

Abstract

In 75 active lead workers the median lead level in finger-bone (bone-Pb), as determined in vivo by an X-ray fluorescence method, was 43 micrograms/g (range less than 20-122). In 32 retired workers the median level was even higher, 59 micrograms/g (range less than 20-135), which indicates a slow turnover rate of lead in finger-bone. This was confirmed in 18 of the "active" workers, in whom bone-Pb was studied in connection with an exposure-free period. In spite of a significant decrease in blood-lead levels (B-Pb), no systematic change of bone-Pb occurred. There was an increase of bone-Pb with time of employment, but with a large interindividual variation. No association was found between bone-Pb and present B-Pb in the active lead workers. However, in the retired ones, B-Pb rose with increasing bone-Pb. The bone-lead pool thus causes an "internal" lead exposure.

Chelated lead and bone lead.

“…These bone lead levels were assessed by in-vivo X-ray fluorescence with 57cobalt as the radiation source (6,10,19,20). The measurement time was 1800 s. The source activity was 0.6 GBq, giving a maximum skin dose of 3 mGy.…”

“…Lead levels in cortical bone , as measured by X-ray fluorescence, have been shown to be a good index of cumulative past exposure, both in finger bone (10) and in tibia (11). However, the relationship between chelatable lead and bone lead levels remains unclear .…”

Using Ionizing Radiation to Determine Trace Element Content in Living Human Subjects

“…Both make use of a thermal neutron capture reaction, 55 Mn(n, ) 56 Mn for manganese 54) and 27 Al(n, ) 28 Al for aluminium 55) . In both cases there is a direct interference from another element present in the body in a higher concentration, 56 Fe(n,p) 56 Mn for manganese, 31 P(n, ) 28 Al for aluminium.…”

“…When bone Pb and blood Pb were examined in retired Pb workers, a strong correlation was observed between the two parameters 28,29,30) . Furthermore, the retired Pb workers had higher blood Pb concentrations than referent groups with no occupational Pb exposure.…”

Lead in Bone: Sampling and Quantitation Using K X-Rays Excited by 109 Cd

“…Their X-ray fluorescence system used 'y-rays from 57Co to excite the K series X-rays of lead. This approach has been further developed (2,3) and adopted elsewhere (4). Sub-sequently, an alternative approach, which used '09Cd rather than 57Co to excite lead K-series X-rays, was proposed (5) and developed (6,7).…”