Best Practices for the Use of Portable X-Ray Fluorescence Analyzers to Screen for Toxic Elements in FDA-Regulated Products

Authors

  • Peter T. Palmer Dept. of Chemistry & Biochemistry San Francisco State University
  • Richard M. Jacobs currently retired, formerly at FDA San Francisco Laboratory
  • Sally Yee FDA San Francisco Laboratory
  • Tao Li FDA San Francisco Laboratory
  • Christopher Reed FDA San Francisco Laboratory
  • Deborah Nebenzahl FDA San Francisco Laboratory
  • Anita Liu FDA Division of West Coast Imports
  • Gordon Chu FDA Division of West Coast Imports
  • Elizabeth MacCorkell FDA Division of West Coast Imports
  • Tracey Duong FDA Division of West Coast Imports
  • Travell Sawyer FDA Division of West Coast Imports
  • Michele Douglas FDA Division of West Coast Imports

DOI:

https://doi.org/10.21423/JRS-V07PALMER

Keywords:

X-Ray Fluorescence, screening, mercury, arsenic, lead, selenium

Abstract

Globalization of trade has made it easy for consumers to purchase products from all over the world. A small fraction of these products contain toxic elements that may pose a health risk to consumers, and there is a clear need for small, portable, and fast methods to rapidly screen these products. Portable X-Ray Fluorescence (XRF) analyzers are the ideal tool for this application, as they involve minimal sample preparation and analysis times of a minute or less. XRF is also well suited for elemental analysis of products that are resistant to traditional hydrochloric/nitric acid digestions such as cosmetics and dietary supplements, and can prevent contamination of expensive Inductively Coupled Plasma Mass Spectrometry (ICP-MS) instruments used for ultra-trace level analyses. Moreover, XRF can be used to monitor most of the elements in the periodic table, with detection limits as low as 1-10 ppm for some elements. This article describes an U.S. Food and Drug Administration (FDA) field study to screen for consumer products containing toxic elements at an International Mail Facility (IMF). After brief training and hands-on activities using real-world samples, two three-person teams using two portable XRF systems analyzed 183 different products over a seven-hour time period, and found 10 that contained significant levels of mercury (Hg), lead (Pb), arsenic (As), and/or selenium (Se), potentially in violation of FDA’s requirements. The goal of this article is to provide guidelines and recommendations for safe, reliable, and efficient use of XRF to screen for toxic elements in FDA-regulated products.

Author Biography

Peter T. Palmer, Dept. of Chemistry & Biochemistry San Francisco State University

Pete Palmer received a B.S. in Chemistry from Canisius College and a Ph.D. in Analytical Chemistry from Michigan State University. After graduation, he worked in the Corporate Research Division of Proctor & Gamble designing and developing laboratory robotics systems, and at NASA Ames Research Center where he led efforts to apply Mass Spectrometry to life support, atmospheric, and ecosystems monitoring applications. Pete is currently a Professor in the Department of Chemistry and Biochemistry at San Francisco State University (SFSU), Co-Director of SFSU’s Mass Spectrometry Facility, and Science Advisor for the FDA. His research interests focus on the development, characterization, and application of highly automated instrumentation for trace chemical analysis. Some of his applications to date include the development of Direct Sampling Mass Spectrometry and Solid Phase Microextraction GC/MS methods for life support and air quality monitoring, development of the first Proton Transfer Reaction Ion Trap Mass Spectrometer for monitoring volatile organic compounds in air, numerous case studies on the determination of pesticide contamination on Native American artifacts, and pioneering the use of X-Ray Fluorescence Spectrometry for rapid screening of toxic elements in consumer products. Pete received the Jefferson Award in 2005 for community service in applying chemical analysis to serve the public interest.  

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Published

2019-07-30

Issue

Vol 7 (2019)

Section

Scientific Articles

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