Radiocarcinogenesis Flashcards
What countries do you think have conducted nuclear weapon tests?
PINK FUS
What are our sources of radiation information?
Nuclear weapons Power Station incidents Military powered vehicle incidents Medical Imaging Occupational Natural environment
Rank the radiation exposure events in terms of severity
Three mile island single PA chest MRT annual occupational exposure Single supine abdomen Chernobyl survivors Hiroshima Bomb survivors
Describe the effect of radiation induced cancers
When a reproductive cell is radiated it can either be damaged and still divide or it can be damaged and it dies. The daughter cell which is damaged can be mutated or it can undergo cell death.
Define radioleukemogenesis
induction or production of leukemia due to radiation
What is the latency peak associated with leukaemia. What are the sources of leukaemia? What is the ratio of death at what exposure associated with leukaemia?
10 year latency peak
Sources
Radiotherapy Ankylosing Spondylitis
Radiotherapy Hyperthyroidism
50 / 10^6 / 10 mSv
What are the sources of thyroid cancer? What is the ratio of death at what exposure associated with thyroid cancer?
Sources
Japanese A Bomb Survivor Cohort studies
Marshall Islanders
Ann Arbour and Rochester enlarged thymus programmes
(Occurrence) 50 - 150 / 10 6 / 10 mSv
(Fatality) 8 / 10 6 / 10 mSv
What are the sources of bone cancer? What is the ratio of death at what exposure associated with bone cancer?
Sources
Radium Clock, watch and dial face painters
5 / 10 6 / 10 mSv
What are the sources of lung cancer and the fatalities?
Sources
Uranium Miners. Bohemia, Czech republic
85 / 10 6 / 10 mSv
What are the sources of breast cancer and the fatalities?
Sources
Japanese A-bomb Survivor Cohort Studies
1940 – 1950. Radiation therapy treatment for post partum mastitis
1930 – 1952. TB Canadian Fluoroscopy Cohort study
20 / 10 6 / 10 mSv
What are the fatalities and the risk associated with Radiation Induced Cancer?
Collectively
500 / 10 6 / 10 mSv
Radiation workers risk estimated to be 400 / 10 6 / 10 mSv
What are the sources for acute and chronic radiation effect knowledge and what are the magnitudes of the effect?
Sources
US Radiologists
Japanese A bomb Survivor Cohort Studies
Magnitude of the Effect
Acute. 1 – 5 % per sievert
Chronic.
What are the stages of a developing embryo?
Preimplantation stage (conception – two weeks) Organogenesis stage (two – eight weeks) Foetal stage (nine weeks – delivery)
What are the sources to research the effects of radiation on a developing embryo?
Human Sources
Japanese A bomb Survivor Cohort Studies
Therapy patients
Animal Studies
Teratogenic effects Pre and neo natal death Growth retardation Abnormalities Post natal induction of cancer
What is the period limitation for the preimplantation stage?
Period from conception until fertilised egg attaches to the uterus wall (generally two weeks).
What is irradiating an embryo at the preimplatation stage?
Irradiation at this stage “all or nothing” effect.
Pre-natal death most significant risk.
Embryos that survive, usually develop normally.
No birth defects were found in Japanese A bomb survivors as a result of irradiation during this stage.
A dose as low as 0.05 Gy can kill at this stage.
LD50/30 is 1 Gy at this stage (based on studies in mice)
What occurs during the organogenesis stage?
Organogenesis – development of major organs