One approach for doublet deconvolution to improve reliability in spectra analysis for in vivo lead measurement

Calculation of lead concentration from K-series X-ray fluorescent studies u ses a robust normalization technique based on the amplitude or area of the elastic signal. Parameter estimation of the elastic signal can be affected by the overlap of the K-beta2 line, especially for concentrations greater t han 40 ppm where the K-beta2 amplitude can be greater than 1% of the elasti c signal. We tested the combination of estimation by method of least moduli and doublet deconvolution. We found that the estimation of the area of the elastic signal is more robust to changes in the low-energy end of the regi on of interest with the combined method than with method of least-squares e stimation and singlet processing. We recommend use of the combined method f or creation of calibration curves at concentrations greater than or equal t o 40 ppm. (C) 2001 Elsevier Science Ltd. All rights reserved.