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Medical Physics Lab Summer 2018. David Fleming
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Medical Physics Lab Summer 2018 David Fleming We use x-ray and gamma ray sources and radiation detectors to probe elemental content of medically relevant samples. We use imaging methods to examine medical samples and materials. We also model and seek to understand distributions of elements in the human body.
Themes • Monitoring and understanding the distribution of lead, arsenic, selenium, strontium, calcium, zinc, manganese, copper, chromium, and other elements using x-ray fluorescence • Approaches range from portable to lab-based to synchrotron, and include computer modeling • Suited for you if interested in medical physics, medicine, biophysics, biomedical engineering, radiation physics, environmental science, public health
Introduction • Pb, Zn, Sr, Ca accumulate in bone • Pb measurement is well established using K-XRF • Zn, Cr, As, and Se accumulate in nails and skin • Summer 2018 seeking up to 3 - 4 research students
Example Results Energy spectrum from a 30 µg/g calibration sample, with As and Se peaks shown in the inset.
Example Results Distribution of As and Se in Sample 1336 (dosed with both As and Se)
Potential Projects • 1. Atlantic PATH: toenail clippings: As, Se, Zn, Cr, coherent scatter…
Potential Projects • 2. uniformity/distribution of Zn in nail (history of exposure; Texas group) • 3. Zn in bone (ALS study; Swedish group)
Potential Projects • 4. synchrotron projects at University of Saskatchewan – elemental mapping and chemical speciation (2019)
Recent Summer Students Chris Roy (U of T; Med Physics) Joanna Mader (Dal; Med School) Kevin Alexander (Queen’s; Med Physics) Maddy Anthonisen (McGill; Biophysics) John Groves (Waterloo; now Engineer) John MacMillan (U of T; Chemistry) Kelly Foran (U of T; Atmospheric Phys) Michael Reno (Dal; Med Physics) Chris Ware (Ottawa; Law School) Craig Groskopf (Moncton Flight College) Stephen Bennett (completing @ MtA) Michel Nader (completing @ MtA) Colby Evans (completing @ MtA)
Recent Summer Students • Craig Groskopf, Stephen Bennett, M Gherase, D Fleming, “Detection of lead in bone phantoms and arsenic in soft tissue phantoms using synchrotron radiation and a portable x-ray fluorescence system”, Physiological Measurement 38: 374 (2017) • D Fleming and Chris Ware, “Portable x-ray fluorescence for the analysis of chromium in nail and nail clippings”, Applied Radiation and Isotopes 121: 91 (2017) • D Fleming, Michel Nader, Kelly Foran, Craig Groskopf, Michael Reno, Chris Ware, M Tehrani, D Guimaraes, P Parsons, “Assessing arsenic and selenium in a single nail clipping using portable X-ray fluorescence”, Applied Radiation and Isotopes 120: 1 (2017)
dfleming@mta.ca David Fleming Thank you!Any questions?