Risk Estimate Slide 13 of 16

Go to slide: 1: Radiation Effects and Risks 2: Radiation Effects on Water 3: Radiation Effects on Water 4: Cell Structure 5: Radiation Effects on Cells 6: Radiation Effects on Cells 7: Radiation Damage and the Results 8: Cell Radiosensitivity 9: General Order of Cell Radiosensitivity 10: Limits of Exposure 11: Radiation Effects 12: Acute Radiation Syndrome 13: Risk Estimate 14: What are the chances? 15: Relative Risk 16: Doses from Various Sources

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The Biological Effects of Ionizing Radiation (BEIR) committee first started to evaluate risk estimates for radiation in the 1950's. The most current committee (BEIR V) has focused on publishing risk primarily associated with external radation exposure data. Information from medical applications and the survivors of the atomic bombs in Japan has been used as a primary source for the knowledge we have today about radiation and its effects on humans. According to BEIR V the risk of death from cancer is 0.08% from doses recieved acutely (all at one time) and might be lower for chronic doses (those recieved over a long period of time and at much lower doses). These risk estimates are an average for all ages, all sexes and all forms of cancer therefore there is a great deal of uncertainty associated with these estimates. These estimates also have limitations based on the following facts. 1. The doses used for the risk assesments are derived from MUCH higher doses than those that are allowed by regulation today. 2. Factors like ethnic origin, nartual levels of cancers, diet, smoking, stress and other biases were not considered in the estimates. 3. The doses recieved by the bomb survivors are many times estimates and not known precisely. * *Sources: Basic Radiation Protection Technology, 1994 and www.physics.isu.edu/radinf/risk.htm