Evaluation of x-ray fluorescence (XRF) lead detection method for candy
by Phipps, Ashley M., M.P.H., UNIVERSITY OF NEVADA, LAS VEGAS, 2009, 63 pages; 1472433

Abstract:

The harmful effects of childhood exposure to environmental lead continue to be a major health concern. Due to the significance of this hazard, a Healthy People 2010 objective was set to reduce all young children's blood lead levels to less than 10 micrograms per deciliter. Identification and removal of lead-contaminated candies is an integral part of the primary prevention of lead poisoning in children.

This research examined the efficacy of a protocol to use a portable XRF to screen candies for lead contamination. Method Detection Limits (MDLs) of 5.45 ppm and 7.05 ppm were determined in the Bulk Sample and Plastics Modes, respectively, using 45 fortified analytical samples with a candy matrix. Results also indicated that the XRF-determined concentrations were significantly different from the actual concentrations, as determined via Graphite Furnace Atomic Absorption Spectrometry (GFAAS). Regression analysis established predictive relationships between XRF data and the actual concentration of lead in candy.

The XRF's current ability to screen candies may be limited to wrappers and highly contaminated samples, as candies are typically seen at concentrations below the MDL. Future research should be done to improve the sensitivity of the XRF, in conjunction with collaborative efforts to gather and disseminate information on the dangers of lead-contaminated candies.

 
AdviserShawn L. Gerstenberger
SchoolUNIVERSITY OF NEVADA, LAS VEGAS
SourceMAI/ 48-02, p. , Dec 2009
Source TypeThesis
SubjectsEnvironmental health; Analytical chemistry
Publication Number1472433
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