Elizabeth S. Roberts-Kirchhoff

Analysis of Dietary Supplements with a Hand-held XRF Analyzer

Nine dietary supplements purchased from various dollar stores and two standard reference materials (SRMs) obtained from the National Institute of Standards and Technology were analyzed using a hand-held X-ray fluorescence (XRF) analyzer. This method of analysis produced rapid results while still keeping the costs low. The results from the analysis of the SRMs with the handheld XRF were within 23% of the reported values for potassium, calcium, and zinc; 11% for manganese and lead; and 6% for titanium and iron. The XRF-determined values for titanium, manganese, iron, zinc, and lead were not statistically, significantly different than those reported for the SRMs. Each dietary supplement contained less than the reported amounts of the expected element and several of the supplements contained additional elements.