RADIATION PROTECTION IN RADIOTHERAPY Part No...., Module No....Lesson No Module title IAEA Training Material on Radiation Protection in Radiotherapy RADIATION PROTECTION IN RADIOTHERAPY Part 3: Radiation Biology PRACTICAL EXERCISE IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

Part No...., Module No....Lesson No Module title Objectives of Part 3 To understand the various effects of radiation on human tissues To appreciate the difference between high and low dose; deterministic and stochastic effects To gain a feel for the order of magnitude of dose and effects To appreciate the risks involved in the use of ionizing radiation as a starting point for a system of radiation protection Part 3, Practical 1 IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

Part 3: Radiation Biology Part No...., Module No....Lesson No Module title IAEA Training Material on Radiation Protection in Radiotherapy Part 3: Radiation Biology Practical 1: Calculation of cancer incidence IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

Part No...., Module No....Lesson No Module title Contents + Objective Appreciate the order of magnitude of radiation induced cancer for relatively small additional long term exposures Perform a simple calculation using information given in the lecture Part 3, Practical 1 IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

Part No...., Module No....Lesson No Module title How many additional cancers would we expect in a population of 1000 people exposed to 5mSv per year for 20years? …and how does this compare with the normal cancer mortality rate? The lecturer can point out that this would be a high estimate for the typical occupational exposure of a pilot or a nuclear medicine technologist. Part 3, Practical 1 IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

Part No...., Module No....Lesson No Module title Assumptions Risk of cancer mortality is 0.05 per Sv (as per ICRP report 60 for low dose rate exposure of the total population) 1,000 people are exposed to 5 mSv/y for 20 y Part 3, Practical 1 IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

Part No...., Module No....Lesson No Module title Questions? Let’s get started... Part 3, Practical 1 IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

Example for Risk Calculation Part No...., Module No....Lesson No Module title Example for Risk Calculation Expected additional cancer deaths is 0.05 [cancers/Sv]x0.005[Sv/y]x20[y]x1,000[people] = 5 additional cancer deaths due to radiation Part 3, Practical 1 IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

Example for Risk Calculation Part No...., Module No....Lesson No Module title Example for Risk Calculation Expected additional cancer deaths is 5 additional cancer deaths due to radiation General population: 23% of all deaths due to cancer Therefore have 230 expected cancer deaths due to other causes... Can we pick 5 additional ones??? Part 3, Practical 1 IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources

Other interesting points... Part No...., Module No....Lesson No Module title Other interesting points... This assumes stochastic effects only Radiation induced cancer are not distinguishable from other cancers (at least not at present) Illustration of the difficulty of producing good epidemiological evidence Calculations become more complex for individual tissue exposures vs. whole body exposures Part 3, Practical 1 IAEA Post Graduate Educational Course in Radiation Protection and Safe Use of Radiation Sources