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.  

References

Anderson, D. L. (2009). Determination of Bromine in Regulated Foods with a Field Portable XRF Analyzer. Journal of AOAC International, 92(2), 502-510.

Anderson, D. L. (2009). Screening of Foods and Related Products for Toxic Elements with a Portable X-Ray Tube Analyzer. Journal of Radioanalytical and Nuclear Chemistry, 282(2), 415-418. doi: 10.1007/s10967-009-0161-0

Arzhantsev, S., Li, X., & Kauffman, J. F. (2011). Rapid Limit Test for Metal Impurities in Pharmaceutical Materials by X-Ray Fluorescence Spectrometry Using Wavelet Transform Filtering. Analytical Chemistry, 83(3), 1061-1068. doi: 10.1021/ac1028598

Bairi, V. G., Kim, J. H., Quevedo, I. R., Mudalige, T. K. & Linder, S. W. (2016). Portable X-Ray Fluorescence Spectroscopy as a Rapid Screening Technique for Analysis of TiO2 and ZnO in Sunscreens. Spectrochimica Acta Part B, Atomic Spectroscopy, 116, 21-27. doi: 10.1016/j.sab.2015.11.008

Davis, D. & Furukawa, H. (2017). Using XRF as an Alternative Technique to Plasma Spectrochemistry for the new USP and ICH Directives on Elemental Impurities in Pharmaceutical Materials. Spectroscopy, 32(7) 12-17.

European Medicines Agency. (2019). Retrieved March 2019 from https://www.ema.europa.eu/en/documents/scientific-guideline/international-conference-harmonisation-technical-requirements-registration-pharmaceuticals-human-use_en-32.pdf

Freemantle, M. (2017, March 29). Mercuric chloride [Audio podcast]. Retrieved January 2019 from https://www.chemistryworld.com/podcasts/mercuric-chloride/3007044.article

International Centre for Diffraction Data. (n.d.). Denver X-Ray Conference [Conference]. Retrieved January 2019 from http://www.dxcicdd.com/

Lanzarotta, A., Witkowski, M., Andria, S., & Crowe, J. (2015). The Establishment of Performance Verification Procedures for Fourier Transform Infrared Spectrometers. Journal of Regulatory Science, 3(1), 1-8.

Lewen, N., Soumeillant, M., Qiu, J., Selekman, J., Wood, S., & Zhu, K. (2015). Use of a Field-Portable XRF Instrument to Facilitate Metal Catalyst Scavenger Screening. Organic Process Research and Development, 19, 2039-2044. doi: 10.1021/acs.oprd.5b00300

London X-ray Consulting Group. (n.d.). A Short Course in XRF Spectrometry. Retrieved January 2019 from http://www.londonxrayconsultinggroup.com/

McIntosh, K. G., Guimaraes, D., Cusack, M. J., Vershinin, A., Chen, Z. W., Yang, K., & Parsons, P. J. (2016). Evaluation of Portable XRF Instrumentation for Assessing Environmental Exposure to Toxic Elements. International Journal of Environmental Analytical Chemistry, 96(1), 15-37. doi: 10.1080/03067319.2015.1114104

Murphy, T. (2015, June). Standard Operating Procedure for XRF Screening of Mercury in Skin Creams. World Bank Project Grant: No. H607-KH. doi: 10.13140/RG.2.1.1435.6648

National Institutes of Health. (1994). Dietary Supplement Health and Education Act of 1994. Retrieved January 2019 from https://ods.od.nih.gov/About/DSHEA_Wording.aspx

Palmer, P. (n.d.). Introduction to Energy-Dispersive X-ray Fluorescence (XRF) - An Analytical Chemistry Perspective [Presentation]. Retrieved January 2019 from http://www.asdlib.org/onlineArticles/ecourseware/Palmer/ASDL%20Intro%20to%20XRF.pdf

Palmer, P.T. (2011). Energy-Dispersive X-Ray Fluorescence Spectrometry -- A Long Overdue Addition to the Chemistry Curriculum. Journal of Chemical Education, 88, 868-872. doi: 10.1021/ed200254v

Palmer, P. T., Hamdani, J., Johnson, R., & Jacobs, R. (2010, August). Use of XRF for Screening and/or Rapid Determination of Toxic Elements in Supplements. FDA Laboratory Information Bulletin #4462, 1-14.

Palmer, P. T., & Jacobs, R. (2007, July). Rapid Determination of Cr in Stainless Steel via XRF. FDA Laboratory Information Bulletin #4398, 1-11.

Palmer, P. T., Jacobs, R., Baker, P. E., Ferguson, K., & Webber, S. (2009). Use of field-portable XRF analyzers for rapid screening of toxic elements in FDA-regulated products. Journal of Agricultural and Food Chemistry, 57, 2605-2613. doi: 10.1021/jf803285h

Palmer, P. T., Jacobs, R., Cross, K., Baker, P. E., & Johnson, R. (2010). Regulatory, Forensic, and Environmental Applications of Field Portable XRF Analyzers. Lab Plus International, (Feb/Mar 2010), 14-17.

Palmer, P. T., Jacobs, R., Vrdoljak, G., Nausin, M., Qiu, C., & Yee, S. (2013, May). Use of Field Portable XRF for Screening and Quantitation of Mercury in Face Creams. FDA Laboratory Information Bulletin #4542, 1-10.

Palmer, P. T., Webber, S., Ferguson, K. & Jacobs, R. (2006, July). On the Suitability of Portable XRF Analyzers for Rapid Screening of Toxic Elements. FDA Laboratory Information Bulletin #4376, 1-15.

Reames, G., & Charlton, V. (2013). Lead detection in food, medicinal, and ceremonial items using a portable X-ray fluorescence (XRF) instrument. Journal of Environmental Health, 75(6), 16-20.

Sanchez-Pomales, G., Mudalige, T., Lim, J-H., & Linder, S. W. (2013). Rapid Screening of Nano-Based Liquid Dietary Supplements for Silver Using a Portable X-Ray Fluorescence Analyzer. Journal of Agricultural and Food Chemistry, 61, 7250-7257. doi: 10.1021/jf402018t

Saper, R. B., Phillips, R. S., Sehgal, A., Khouri, N., Davis, R. B., Paquin, J., . . . Kales, S. N. (2008). Lead, mercury, and arsenic in US- and Indian-manufactured Ayurvedic medicines sold via the Internet. Journal of the American Medical Association, 300}, 915-923. doi: 10.1001/jama.300.8.915

Seyfarth, A., & Kaiser, B. (2013, September). History of Handheld XRF. Bruker FIRST Newsletter, 23, 1-6.

Shrivastava, P., O'Connell, S., & Whitley, A. (2005, May). Handheld x-ray fluorescence: practical application as a screening tool to detect the presence of environmentally-sensitive substances in electronic equipment, Proceedings of the 2005 IEEE International Symposium on Electronics and the Environment, 2005, New Orleans, LA. doi: 10.1109/ISEE.2005.1437013

U.S. Environmental Protection Agency. (2007, February). Method 6200 -- Field Portable X-Ray Fluorescence Spectrometry for the Determination of Elemental Concentrations in Soil and Sediment. Retrieved January 2019 from https://www.epa.gov/sites/production/files/2015-12/documents/6200.pdf

U.S. Food and Drug Administration. (2016). Guidance Document: Lead in Cosmetic Lip Products and Externally Applied Cosmetics: Recommended Maximum Level. Retrieved from https://www.fda.gov/regulatory-information/search-fda-guidance-documents/draft-guidance-industry-lead-cosmetic-lip-products-and-externally-applied-cosmetics-recommended

U.S. Food and Drug Administration. (2018). Lead acetate, 21 CFR § 73.2396. Retrieved June 2019 from https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=73.2396

U.S. Food and Drug Administration. (2018). Use of mercury compounds in cosmetics including use as skinbleaching agents in cosmetic preparations also regarded as drugs, 21 CFR § 700.13. Retrieved January 2019 from https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfCFR/CFRSearch.cfm?fr=700.13&SearchTerm=mercury

U.S. Pharmacopeia. (2016, May 1). <232> Elemental Impurities -- Limits, USP 39. Retrieved January 2019 from https://www.usp.org/sites/default/files/usp/document/our-work/chemical-medicines/key-issues/c232-usp-39.pdf

Van Grieken, R., & Markowicz, A. (2001). Handbook of X-Ray Spectrometry. Boca Raton, FL: CRC Press.

Vrdoljak, G. A., Palmer, P. T., Moezzi, B., & Viegas, A. (2019). Comparison of XRF, TXRF, and ICP-MS Methods for Determination of Mercury in Face Creams, Toxics. Manuscript in preparation.

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Published

2019-07-30

Issue

Vol 7 (2019)

Section

Scientific Articles

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How to Cite

Best Practices for the Use of Portable X-Ray Fluorescence Analyzers to Screen for Toxic Elements in FDA-Regulated Products. (2019). Journal of Regulatory Science, 7, 1-11. https://doi.org/10.21423/JRS-V07PALMER