1. 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

2. 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

3. 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

4. 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

5. 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

6. 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

7. 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

8. 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

9. 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

10. 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