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Ionizing and Non-Ionizing Radiation-Induced Adaptive Response: Findings From E arth to S pace

Ionizing and Non-Ionizing Radiation-Induced Adaptive Response: Findings From E arth to S pace. SMJ Mortazavi Prof. of Medical Physics Shiraz University of Medical Sciences mmortazavi@sums.ac.ir. Paracelsus (1493-1541). "All substances are poisons; there is none which is not a poison.

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Ionizing and Non-Ionizing Radiation-Induced Adaptive Response: Findings From E arth to S pace

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  1. Ionizing and Non-Ionizing Radiation-Induced Adaptive Response: Findings From Earth to Space SMJ Mortazavi Prof. of Medical Physics Shiraz University of Medical Sciences mmortazavi@sums.ac.ir

  2. Paracelsus (1493-1541) • "All substances are poisons; there is none which is not a poison. • The right dose differentiates a poison…." Mortazavi SMJ, Ph.D

  3. Hormesis • All chemical substances will exhibit a toxic effect given a large enough dose. • If the dose is low enough even a highly toxic substance will cease to cause a harmful effect. • The toxic potency of a chemical is thus ultimately defined by the dose (the amount) of the chemical that will produce a specific response in a specific biological system. • Source: http://learn.caim.yale.edu/chemsafe/references/dose.html Mortazavi SMJ, Ph.D

  4. LNT & Radiation Hormesis • The radiation hormesis model, unlike the LNT model, assumes that adaptive/protective mechanisms can be stimulated by low-dose radiation and that they can prevent both spontaneous and toxicant-related cancers as well as other adverse health effects (Calabrese et al. 2007). Mortazavi SMJ, Ph.D

  5. Natural radiation deficiency symptoms • It has been long known that protozoa and bacteria exposed to artificially lowered levels of natural radiation demonstrate deficiency symptoms expressed as dramatically decreased proliferation. Mortazavi SMJ, Ph.D

  6. Mortazavi SMJ, Ph.D

  7. Mortazavi SMJ, Ph.D

  8. Mortazavi SMJ, Ph.D

  9. Mortazavi SMJ, Ph.D

  10. Mortazavi SMJ, Ph.D Radon & Lung Cancer in Ramsar, Iran • Radon levels in some dwellings are up to 3700 Bq/m3 (over 100 pCi/L). • The people and their ancestors exposed to abnormally high radiation levels over many generations. • If a radiation dose of a few hundred mSvper year is detrimental to health causing genetic abnormalities or an increased risk of cancer, it should be evident in these people. Mortazavi SMJ, M. Ghiassi-Nejad and M. Rezaiean. Cancer risk due to exposure to high levels of natural radon in the inhabitants of Ramsar, Iran in: High Levels of Natural Radiation and Radon Areas: Radiation Dose and Health Effects, T. Sugahara, M. Morishima, M. Sohrabi, Y Sasaki, I. Hayata, and S. AkibaEds, pp. 436-437, Elsevier, Amsterdam, 2005.

  11. Mortazavi SMJ, Ph.D Study Design • Ramsarwas divided into eight health districts and a health center provided primary health services in each health district. • Indoor radon concentration levels were previously measured in each dwelling by the Iranian Nuclear Regulatory Authority experts. Mortazavi SMJ, M. Ghiassi-Nejad and M. Rezaiean. Cancer risk due to exposure to high levels of natural radon in the inhabitants of Ramsar, Iran in: High Levels of Natural Radiation and Radon Areas: Radiation Dose and Health Effects, T. Sugahara, M. Morishima, M. Sohrabi, Y Sasaki, I. Hayata, and S. AkibaEds, pp. 436-437, Elsevier, Amsterdam, 2005.

  12. Mortazavi SMJ, Ph.D Cancer Mortality • The overall cancer mortality, lung cancer mortality and neonatal death rate of different districts in the years from 2000 to 2001 were collected. • The radon prone houses were located in a district named Ramak. Mortazavi SMJ, M. Ghiassi-Nejad and M. Rezaiean. Cancer risk due to exposure to high levels of natural radon in the inhabitants of Ramsar, Iran in: High Levels of Natural Radiation and Radon Areas: Radiation Dose and Health Effects, T. Sugahara, M. Morishima, M. Sohrabi, Y Sasaki, I. Hayata, and S. AkibaEds, pp. 436-437, Elsevier, Amsterdam, 2005.

  13. Mortazavi SMJ, Ph.D Surprising Results • Our study showed that the highest lung cancer mortality rate was in GaleshMahaleeh, where the radon levels were normal. • On the other hand, the lowest lung cancer mortality rate was in Ramak, where the highest concentrations of radon in the dwellings were found Mortazavi SMJ, M. Ghiassi-Nejad and M. Rezaiean. Cancer risk due to exposure to high levels of natural radon in the inhabitants of Ramsar, Iran in: High Levels of Natural Radiation and Radon Areas: Radiation Dose and Health Effects, T. Sugahara, M. Morishima, M. Sohrabi, Y Sasaki, I. Hayata, and S. AkibaEds, pp. 436-437, Elsevier, Amsterdam, 2005.

  14. Mortazavi SMJ, Ph.D Crude Lung Cancer Rate Mortazavi SMJ, M. Ghiassi-Nejad and M. Rezaiean. Cancer risk due to exposure to high levels of natural radon in the inhabitants of Ramsar, Iran in: High Levels of Natural Radiation and Radon Areas: Radiation Dose and Health Effects, T. Sugahara, M. Morishima, M. Sohrabi, Y Sasaki, I. Hayata, and S. AkibaEds, pp. 436-437, Elsevier, Amsterdam, 2005.

  15. Mortazavi SMJ, Ph.D Adjusted Lung Cancer Rate Mortazavi SMJ, M. Ghiassi-Nejad and M. Rezaiean. Cancer risk due to exposure to high levels of natural radon in the inhabitants of Ramsar, Iran in: High Levels of Natural Radiation and Radon Areas: Radiation Dose and Health Effects, T. Sugahara, M. Morishima, M. Sohrabi, Y Sasaki, I. Hayata, and S. AkibaEds, pp. 436-437, Elsevier, Amsterdam, 2005.

  16. Mortazavi SMJ, Ph.D The Study of Tumor Markersin High Background Radiation Areas Source: S Taeb, SMJ Mortazavi, A Ghaderi, H Mozdarani, MR Kardan, SAR Mortazavi, A Soleimani, I Nikokar, M Haghani, A Soofi. Alterations of PSA, CA15.3, CA125, Cyfra21-1, CEA, CA19.9, AFP and Tag72 tumor markers in human blood serum due to long term exposure to high levels of natural background radiation in Ramsar, Iran. International Journal of Radiation Research. in press.

  17. Mortazavi SMJ, Ph.D Why Tumor Markers? • Recently, as no excess cancer rate was reported in these areas by epidemiological studies, we studied the tumor markers in the inhabitants of these areas to shed some light on the impact of high levels of background radiation on cancer induction.

  18. Mortazavi SMJ, Ph.D Methods • The level of background gamma radiation as well as indoor radon was determined using RDS-110 and CR dosimeters. • Thirty five individuals from a high background radiation area (HBRA) and 35 individuals from a normal background radiation area (NBRA) were randomly selected to participate in the study. • Commercial ELISA kits (sandwich type ELISA tests) were used to measure the serum levels of PSA, CA15.3, CA125, Cyfra21-1, CEA, CA19.9, AFP and Tag72 tumor markers.

  19. Mortazavi SMJ, Ph.D Results • Among the eight biomarkers investigated, the means of PSA, CA15.3, CA125, CA19.9 and AFP concentrations between the HBRAs and NBRAs were not different. • However, Cyfra21, CEA and Tag72 in HBRA group revealed significant increases compared to those of NBRA group (P<0.05). • Statistically significant correlation between the external gamma dose as well as indoor radon level and the concentration of CEA (P<0.001), Cyfra-21(P<0.001) and TAG 72 (P<0.001 and 0.01 respectively) biomarkers were also observed.

  20. Thank you Mortazavi SMJ, Ph.D

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