1. THE LEGITIMACY OF THE RADIATION HORMESIS HYPOTHESIS Malek Elsayyid Mentor: Dr. Eickmeyer

2. OVERVIEW What is ionizing radiation? How does radiation affect DNA replication/can radiation cause genetic mutations? Do “low doses” of radiation have good, bad, or no effect on you?

3. IONIZING RADIATION DEFINITION: “Ionizing radiation is any type of particle or electromagnetic wave that carries enough energy to ionize or remove electrons from an atom.” Doss, H. M. "Ionizing Radiation and Humans – The Basics." Physics Central. APS Physics. Web. 21 Feb. 2016..

4. IONIZING ELECTROMAGNETIC WAVES The two types of electromagnetic waves that have enough energy to ionize atoms are X-rays and gamma- rays. Lucas, Jim. "What Is Electromagnetic Radiation?" LiveScience. TechMedia Network, 12 Mar. 2015. Web. 21 Feb. 2016..

5. IONIZING PARTICLES The most common types of particles that can ionize atoms are Alpha, Beta, and Muon particles. Alpha particle= Helium nucleus (2 protons, 2 neutrons) Beta particle= A high energy, high speed electron or positron Muon= “Heavy electron.” A major component of cosmic rays at sea level, they are created in the upper atmosphere by nuclear reactions. "The Beta Particle." The Radiation Information Network. Idaho State University. Web. 21 Feb. 2016..

6. Alpha Particle EmissionBeta Particle Emission Alpha and Beta particles come from the decay of radioactive nuclei or neutrons.

7. HOW DOES IONIZING RADIATION AFFECT YOUR DNA? Ionizing waves/particles can break bonds and interact with DNA in two main ways: Directly ionizing DNA molecules, or neighboring molecules which will then ionize DNA. Indirectly, by creating Free Radicals, which interact with DNA. If particles directly or indirectly interact with DNA molecules, they can damage vital gene sequences. Some of these genes include those responsible for cell replication, which if damaged can cause cells to replicate uncontrollably as seen in Cancer cells.

8. WHAT ABOUT “LOW DOSE” RADIATION? Three main arguments: 1.Linear-no threshold model 2.Threshold model 3.??????????? Radiation Hormesis

9. GRAPHS OF MODELS http://tech.snmjournals.org/cgi/content-nw/full/31/1/11/F2

10. AREA OF CONTROVERSY Most data are from epidemiological studies that extrapolate damage to health of low doses from high dose data. Oka, Yoshiaki. "The Fukushima Daiichi Nuclear Plant Accident Caused by the Massive Tsunami." The Great East Japan Earthquake:Opinion:WASEDA ONLINE. The Japan News. Web. 22 Feb. 2016..

11. MY QUESTION Which model is the best one? Why?

12. WHAT TO INVESTIGATE What is the minimum amount of radiation required to affect DNA? What mechanisms do our cells have to repair themselves from low dose radiation? Is there a point (or threshold) where those mechanisms will fail to work? If so, what is that threshold? How would we determine it? Would it be wise to be exposed to a level of radiation below that threshold for a long period of time?

13. CITATIONS Doss, H. M. "Ionizing Radiation and Humans – The Basics." Physics Central. APS Physics. Web. 21 Feb. 2016.. Lucas, Jim. "What Is Electromagnetic Radiation?" LiveScience. TechMedia Network, 12 Mar. 2015. Web. 21 Feb. 2016.. Oka, Yoshiaki. "The Fukushima Daiichi Nuclear Plant Accident Caused by the Massive Tsunami." The Great East Japan Earthquake:Opinion:WASEDA ONLINE. The Japan News. Web. 22 Feb. 2016.. "The Beta Particle." The Radiation Information Network. Idaho State University. Web. 21 Feb. 2016..