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rad bio ch 36
radiation biology ch 36
| Question | Answer |
|---|---|
| Stochastic effects are | late effects of radiation |
| What type of curve do radiation protection guidelines follow? | linear nonthreshold |
| Where does radiation induced cataracts occur? | the posterior pole of the lens |
| What effets do high LET radiation have on the eye? | will cause cataracts 100% of the time |
| What type of curve do cataracts follow? | nonlinear threshold |
| At worst, what amount of lifespan shortening can be expected from radiation exposure? | 10 days per rad |
| What is the formula for relative risk? | observed cases/expected cases |
| What type of curve does leukemia follow? | linear nonthreshold |
| What is the latent period for leukemia? | 4-7 years |
| What is the at risk period for leukemia? | 20 years |
| What is the latent period for cataracts? | 5-30 years |
| What was the An Arbor series? | peds 20-30 rad to the thymus, 1940’s-50’s late effects thyroid cancer |
| What was the Rochester Series? | peds 300 rad to thymus, 1940’s-50’s late effect thyroid cancer |
| What was the Rongelap Atoll case? | atomic bomb testing fallout exposure. 1200 rad to thyroid |
| What type of curve does thyroid cancer follow? | linear nonthreshold |
| What is the half life of radium? | 1620 years |
| How much radium was the maximum ingested by the watch dial painters? | 500 Gy (50,000 rad) |
| What type of curve do skin cancers follow? | threshold |
| What is the latent period for skin cancers? | 5-10 years |
| What is the relative risk for rad techs and breast cancer? | 1.13 |
| BEIR | Biologic Effectiveness of Ionizing Radiation |
| What is the most radiosensitive phase for the fetus? | 1st trimester (weeks 2-10) |
| What is the most radiorestistant phase for the fetus? | weeks 0-2 |
| How much does 10 rad increase the risk of congenital abnormalities? | 1% (norm. is 5%) |
| How much does 10 rad increase the risk of spontaneous abortion? | .1% (norm 25%) |
| What is the period of major organogenesis for a fetus? | weeks 2-10 |
| When might DNA damage occur to the fetus with radiation exposure? | weeks 2-10 |
| when does skeletal development occur for the fetus? | weeks 2-6 |
| when does cognitive development occur for the fetus? | weeks 6-10 |
| how much does 10 rad increase the likeliness of mental retardation? | .5% (norm 6%) |
| what is the doubling dose for humans? | 50-250 rad |
| at what exposure level are abnormalities with pregnancy increased, potentially leading to a therapeutic abortion? | 20-25 rad |