Effects of Long-term exposure to Radiation - Week 3

Question 1

Branch of medical science that deals with the incidence, distribution, and control of disease in a population

Answer 1

Epidemiology

Question 2

Limitations on epidemiologic studies

Answer 2

1. failure to control experimental group for other known carcinogens
2. Insufficient observation times for cancers with long latent time
3. using improper control groups
4. deficient or incorrect health records

Question 3

Dose response relationship for radiation induced malignancies

Answer 3

linear nonthreshold

Question 4

Cancers that are induced by ionizing radiation (6)

Answer 4

Leukemia, skin carcinoma, thyroid, breast, osteosarcoma, lung

Question 5

Latent period for leukemia

Answer 5

4-7 years

Question 6

dose response for leukemia

Answer 6

linear nonthreshold

Question 7

latent period for skin carcinoma

Answer 7

5-10 years

Question 8

dose response for skin cardinoma

Answer 8

linear threshold

Question 9

dose response for thyroid cancer

Answer 9

linear nonthreshold

Question 10

Absolute risk for breast cancer

Answer 10

6 cases/1 million persons/rad/year

Question 11

Absolute risk for osteosarcoma

Answer 11

0.11 cases/106 persons/rad/year

Question 12

dose response relationship for lung cancer

Answer 12

Linear nonthreshold

Question 13

Populations used as sources of data on the incidence of radiation induced cancer

Answer 13

1. atomic bomb survivors
2. medically exposed patients
3. occupationally exposed personnel
4. populations who receive high natural background exposure

Question 14

Explains how age at the time of radiation exposure may influence cancer risk estimate

Answer 14

Relative (multiplicative) risk model

Question 15

Equation to calculate relative risk

Answer 15

observed cases/expected cases

Question 16

Estimates a continual increase in risk that is independent of the spontaneous age-specific risk at the time of exposure

Answer 16

Absolute (additive) risk model

Question 17

States risks in terms of number of cases/1 million persons/rad/year

Answer 17

absolute risk

Question 18

Number of excess cases observed compared with the expected spontaneous occurence

Answer 18

Excess Risk

Question 19

Equation to calculate excess risk

Answer 19

observed cases-expected cases

Question 20

An average calculated from the gonadal dose received by the entire population

Answer 20

Genetically Significant Dose

Question 21

The dose of radiation required per generation to double the spontaneous mutation rate

Answer 21

Doubling Dose

Question 22

Stage of pregnancy where congenital abnormalities are most likely to form following irradiation in utero

Answer 22

organogenesis stage

Question 23

What does the embryos response to radiation depend on?

Answer 23

1. total dose
2. rate of dose
3. quality of radiation
4. stage of development

Question 24

Effect that appears randomly in nature and cannot be determined. increases probability of effect

Answer 24

Stochastic

Question 25

Effects and severity can be determined by dose

Answer 25

Deterministic
Non-stochastic

Question 26

Appears over the course of several years

Answer 26

Long-term effects

Question 27

Appears within hours to a few months after exposure

Answer 27

short-term effects