Seminar: The feasibility of in-vivo detection of tungsten in human bone using X-ray fluorescence (XRF) technique

Student: Sajed Mcheik

Supervisor: Dr. Ana Pejovic-Milic

Abstract:

Tungsten was treated for a long time as a non-reactive, dull metal with unknown health effect until
it was investigated for its association to the increase of childhood leukemia in Fallon, Nevada since
1997 where the concentration of tungsten in water was relatively high [1,2,3,4]. In addition,
according to recent studies, human exposure to tungsten could lead to adverse health effects
including tumour promotion, pulmonary dysfunction, and immune dysfunction [5]. Furthermore,
recent studies suggested of using sodium tungstate as anti-diabetic treatment [6,7,8,9] and using
tungsten nanoparticles to enhance radiation therapy [10] which could increase tungsten exposure.
According to International Commission on Radiological Protection (ICRP) (1980,2001) biokinetic
model, tungsten can enter the body through inhalation, ingestion, and absorption through the skin.
According to the biokinetic model, 95% of tungsten entered the blood stream will be excreted by
urine or feces while 2.5 % are retained in the bone mineral in which 30% of tungsten will remain
in the bone after 1000 days [11] and hence it is very important to monitor tungsten level in bone
to assess the health of exposed people. In our study, we developed a non-invasive detection system
that use X-ray fluorescence (XRF) technique to detect tungsten in bone by building hydroxyapatite
phantoms that mimic bone which is doped with different tungsten concentration between 0 and 50
ppm W/Ca. The system used Cd-109 as source of X-ray and HPGe detector. The minimum
detection limit (MDL) of the system using TOPAS simulation was found to be equal to 4.5 ppm
W/Ca based on a soft tissue thickness of 5 mm for 109 particles.

1. Schell, J., & Pardus, M. (2008). Tungsten and cobalt in Fallon, Nevada: Association with childhood
leukemia. Environmental Health Perspectives, 116(5), A196-A197.
2. Steinberg, K. K., Relling, M. V., Gallagher, M. L., Greene, C. N., Rubin, C. S., French, D., Satten, G.
A. (2007). Genetic studies of a cluster of acute lymphoblastic leukemia cases in churchill county,
nevada. Environmental Health Perspectives, 115(1), 158-164.
3. Rubin, C. S., Holmes, A. K., Belson, M. G., Jones, R. L., Flanders, W. D., Kieszak, S. M., Osterloh, J.,
Luber, G. E., Blount, B. C., Barr, D. B., Steinberg, K. K., Satten, G. A., McGeehin, M. A., & Todd, R.
L. (2007). Investigating childhood leukemia in Churchill County, Nevada. Environmental Health
Perspectives, 115(1), 151-157.
4. Sheppard, P. R., Speakman, R. J., Ridenour, G., & Witten, M. L. (2007). Temporal variability of
tungsten and cobalt in Fallon, Nevada. Environmental Health Perspectives, 115(5), 715-719.
5. Bolt, A. M., & Mann, K. K. (2016). Tungsten: An emerging toxicant, alone or in
combination. Current Environmental Health Reports, 3(4), 405-415.
doi:10.1007/s40572-016-0106-z
6. Barberà, A., Gomis, R. R., Prats, N., Rodríguez-Gil, J. E., Domingo, M., Gomis, R., & Guinovart, J. J.
(2001). Tungstate is an effective antidiabetic agent in streptozotocin-induced diabetic rats: A longterm study. Diabetologia, 44(4), 507-513
7. Zafra, D., Nocito, L., Domínguez, J., & Guinovart, J. J. (2013). Sodium tungstate activates glycogen
synthesis through a non-canonical mechanism involving G-proteins. FEBS Letters, 587(3), 291-
296.
8. Bertinat, R., Westermeier, F., Gatica, R., & Nualart, F. (2019;2018;). Sodium
tungstate: Is it a safe option for a chronic disease setting, such as
diabetes? Journal of Cellular Physiology, 234(1), 51-60.
9. Bertinat, R., Westermeier, F., Silva, P., Gatica, R., Oliveira, J. M., Nualart, F.,
Gomis, R., & Yáñez, A. J. (2018). The antidiabetic agent sodium tungstate induces
abnormal glycogen accumulation in renal proximal tubules from diabetic IRS2-
knockout mice. Journal of Diabetes Research, 2018, 5697970-10.
10.Jakhmola, A., Anton, N., Anton, H., Messaddeq, N., Hallouard, F., Klymchenko, A.,
Mely, Y., & Vandamme, T. F. (2013;2014;). Poly- ε -caprolactone tungsten oxide
nanoparticles as a contrast agent for X-ray computed
tomography. Biomaterials, 35(9), 2981-2986.
11.ICRP 1981: Limits for intakes of radionuclides by workers.
Commission of Radiological Protection. ICRP Publication
30, Part 3. Pergamon Press, New York, 93–95.