Performance appraisals of digital spectroscopy systems for the measurement of bone lead

The performances of two new digital spectroscopy systems are compared to a conventional analogue amplifier ADC system for the 109Cd based K X-ray fluorescence in vivo measurement of bone lead. Canberra's DSA-2000 and ORTEC's DSPEC(PLUS) were found to show 27.3 and 10.8% improvements in measurement precision respectively, when compared to an optimized conventional system. The resulting improvements in minimum detection limit, compared with the conventional limit of 6-10 microg Pb/g bone mineral, were reductions of 1.5-2.5 microg Pb/g bone mineral for the DSA-2000, and 0.5-1.0 microg Pb/g bone mineral for the DSPEC(PLUS).