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Radiation Biology: a Handbook for Teachers and Students

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Radiation Biology: A Handbook for Teachers and Students VIENNA, 2010 TRAINING COURSE SERIES42 RADIATION BIOLOGY: A HANDBOOK FOR TEACHERS AND STUDENTS TRAINING COURSE SERIES No. 42 The following States are Members of the International Atomic Energy Agency: AFGHANISTAN GHANA NORWAY ALBANIA GREECE OMAN ALGERIA GUATEMALA PAKISTAN ANGOLA HAITI PALAU ARGENTINA HOLY SEE PANAMA ARMENIA HONDURAS PARAGUAY AUSTRALIA HUNGARY PERU AUSTRIA ICELAND PHILIPPINES AZERBAIJAN INDIA POLAND BAHRAIN INDONESIA PORTUGAL BANGLADESH IRAN, ISLAMIC REPUBLIC OF QATAR BELARUS IRAQ REPUBLIC OF MOLDOVA BELGIUM IRELAND ROMANIA BELIZE ISRAEL RUSSIAN FEDERATION BENIN ITALY SAUDI ARABIA BOLIVIA JAMAICA BOSNIA AND HERZEGOVINA JAPAN SENEGAL BOTSWANA JORDAN SERBIA BRAZIL KAZAKHSTAN SEYCHELLES BULGARIA KENYA SIERRA LEONE BURKINA FASO KOREA, REPUBLIC OF SINGAPORE BURUNDI KUWAIT SLOVAKIA CAMBODIA KYRGYZSTAN SLOVENIA CAMEROON LATVIA SOUTH AFRICA CANADA LEBANON SPAIN CENTRAL AFRICAN LESOTHO SRI LANKA REPUBLIC LIBERIA SUDAN CHAD LIBYAN ARAB JAMAHIRIYA SWEDEN CHILE LIECHTENSTEIN SWITZERLAND CHINA LITHUANIA SYRIAN ARAB REPUBLIC COLOMBIA LUXEMBOURG TAJIKISTAN CONGO MADAGASCAR THAILAND COSTA RICA MALAWI THE FORMER YUGOSLAV CÔTE D’IVOIRE MALAYSIA REPUBLIC OF MACEDONIA CROATIA MALI TUNISIA CUBA MALTA TURKEY CYPRUS MARSHALL ISLANDS UGANDA CZECH REPUBLIC MAURITANIA UKRAINE DEMOCRATIC REPUBLIC MAURITIUS UNITED ARAB EMIRATES OF THE CONGO MEXICO UNITED KINGDOM OF DENMARK MONACO GREAT BRITAIN AND DOMINICAN REPUBLIC MONGOLIA NORTHERN IRELAND ECUADOR MONTENEGRO EGYPT MOROCCO UNITED REPUBLIC EL SALVADOR MOZAMBIQUE OF TANZANIA ERITREA MYANMAR UNITED STATES OF AMERICA ESTONIA NAMIBIA URUGUAY ETHIOPIA NEPAL UZBEKISTAN FINLAND NETHERLANDS VENEZUELA FRANCE NEW ZEALAND VIETNAM GABON NICARAGUA YEMEN GEORGIA NIGER ZAMBIA GERMANY NIGERIA ZIMBABWE The Agency’s Statute was approved on 23 October 1956 by the Conference on the Statute of the IAEA held at United Nations Headquarters, New York; it entered into force on 29 July 1957. The Headquarters of the Agency are situated in Vienna. Its principal objective is “to accelerate and enlarge the contribution of atomic energy to peace, health and prosperity throughout the world’’. RADIATION BIOLOGY: A HANDBOOK FOR TEACHERS AND STUDENTS INTERNATIONAL ATOMIC ENERGY AGENCY VIENNA, 2010 COPYRIGHT NOTICE All IAEA scientific and technical publications are protected by the terms of the Universal Copyright Convention as adopted in 1952 (Berne) and as revised in 1972 (Paris). The copyright has since been extended by the World Intellectual Property Organization (Geneva) to include electronic and virtual intellectual property. Permission to use whole or parts of texts contained in IAEA publications in printed or electronic form must be obtained and is usually subject to royalty agreements. Proposals for non-commercial reproductions and translations are welcomed and considered on a case-by-case basis. Enquiries should be addressed to the IAEA Publishing Section at: Sales and Promotion, Publishing Section International Atomic Energy Agency Vienna International Centre PO Box 100 1400 Vienna, Austria fax: +43 1 2600 29302 tel.: +43 1 2600 22417 email: [email protected] http://www.iaea.org/books For further information on this publication, please contact: Applied Radiation Biology and Radiotherapy Section International Atomic Energy Agency Vienna International Centre PO Box 100 1400 Vienna, Austria email: [email protected] RADIATION BIOLOGY: A HANDBOOK FOR TEACHERS AND STUDENTS IAEA, VIENNA, 2010 IAEA-TCS-42 ISSN 1018-5518 © IAEA, 2010 Printed by the IAEA in Austria March 2010 FOREWORD Knowledge of the radiobiology of normal tissues and tumours is a core prerequisite for the practice of radiation oncology. As such the study of radiobiology is mandatory for gaining qualification as a radiation oncologist in most countries. Teaching is done partly by qualified radiobiologists in some countries, and this is supplemented by teaching from knowledgeable radiation oncologists. In low and middle income (LMI) countries the teachers are often radiation oncologists and/or medical physicists. In Europe, a master’s course on radiobiology is taught jointly by a consortium of five European Universities. This is aimed at young scientists from both Western and Eastern Europe, training in this discipline. Recently the European Society for Therapeutic Radiology and Oncology (ESTRO) initiated the launch of a radiobiology teaching course outside Europe (Beijing, 2007; Shanghai, 2009). Radiation protection activities are governed by many regulations and recommendations. These are based on knowledge gained from epidemiological studies of health effects from low as well as from high dose radiation exposures. Organizations like the International Commission on Radiological Protection (ICRP) have put a lot of effort into reviewing and evaluating the biological basis to radiological protection practices. Personnel being trained as future radiation protection personnel should have a basic understanding of the biological and clinical basis to the exposure limitations that they are subject to and that they implement for industrial workers and the public at large. It is for these reasons that aspects of Radiobiology related to protection issues are included in this teaching syllabus. In LMI countries, many more teachers are needed in radiobiology, and the establishment of regional training centres or special regional training courses in radiobiology, are really the only options to solve the obvious deficit in knowledge of radiobiology in such countries. Radiobiology teaching courses organized or sponsored by the IAEA are oversubscribed, and the students themselves confirm the great need for this type of teaching. Requests have been received from a number of countries in all regions asking for the IAEA to help organize radiobiology teaching. More qualified professionals are also needed for this exercise. Already there are some initiatives e.g. an IAEA project produced in 2007 a distance-learning course in the Applied Sciences of Oncology (ASO) for Radiation Oncologists (also available on the IAEA-website since 2008) including 10 modules in radiobiology. This handbook for teachers and students was formulated based on the recommendations of a Consultants Meeting on International Syllabus for Radiobiology Teaching held 12-14 December 2005 in Vienna, Austria. Whilst this information is available in various books and other reports, it is summarized and collated here so that the whole document has a degree of completeness. This should be helpful in particular to those countries that do not have easy access to appropriate books and reports. Comments and suggestions on this syllabus as a teaching tool were sought from committees of the ESTRO and ASTRO (American Society for Therapeutic Radiology and Oncology). This handbook is written in two parts: (a) Teaching programme including a common basic radiobiology education and teaching programme for radiation oncologists, radiation therapy technologists, diagnostic radiologists, radiation biologists, medical physicists, radiation protection officers and other disciplines involved in radiation activities. This will take 1 week of teaching (30 hours), including a practical or tutorial session at the end of each day. This is followed by a further week of advanced teaching for radiation oncologists, and a further 3 days for radiation protection personnel. (b) Minimal Essential Syllabus for Radiobiology and two extra modules for radiation oncologists and radiation protection personnel, respectively. For each discipline, the basic module and an extra module would constitute the minimum essential syllabus and teaching requirements. It is hoped that this handbook for teachers and students will fulfil the needs of the Member States and serves the basis for regulatory requirements in these countries. The IAEA officer responsible for this publication is J. Wondergem of the Division of Human Health. CONTENTS 1. TEACHING PROGRAMME........................................................................................... 1 2. MINIMUM ESSENTIAL SYLLABUS FOR RADIOBIOLOGY................................. 13 2.1. Introduction ...................................................................................................... 13 2.2. Physics and chemistry of radiation interactions with matter............................ 13 2.2.1. Sources of ionizing radiation ................................................................ 13 2.2.2. Types of ionizing radiation................................................................... 14 2.2.3. Particulate radiations............................................................................. 19 2.2.4. Linear energy transfer........................................................................... 20 2.2.5. Radiation dose and units....................................................................... 21 2.2.6. Principles of radiation dosimetry.......................................................... 22 2.2.7. Direct and indirect effects..................................................................... 23 2.3. Molecular and cellular radiobiology................................................................. 26 2.3.1. Radiation lesions in DNA..................................................................... 26 2.3.2. Major types of DNA repair................................................................... 26 2.3.3. Damage recognition and signalling ...................................................... 27
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