Lecture 7

Question 1

Deterministic effects occur above?

Answer 1

0.2Gy and higher

Question 2

Factors of stochastic effects?

Answer 2

Dose
Number of affected cells
Sensitivity

Question 3

Dose response relationship for stochastic effects

Answer 3

Unclear unlike deterministic effects

Epidemiological studies can provide statistical associations

Question 4

Cancer risks with low doses of ionising radiation ?

Answer 4

Is not very clear

Question 5

LNT curve

Answer 5

Straight

Question 6

Downwardly decreasing slope?

Answer 6

indicates small number of hypersensitive individuals
Primary radiation dose
Bystander effects

Question 7

Upward curving slope

Answer 7

Good description for induction of Leukaemia and chromosome aberrations

Question 8

Threshold curve

Answer 8

Indicates a threshold for induction of sarcomas

Question 9

Hormetic relationships

Answer 9

Favourable response to low doses of radiation exposure (hormesis)

Question 10

Doubts about validity of LNT model/

Answer 10

-Cells are not affected by accumulating lesions
-Doses below 10mSv are eliminated by death
Doses slightly higher result in misrepair or irreversible lesions

Question 11

Total risk of exposure to IR (population)

Answer 11

500 per million of general population exposed to 10mSV

Question 12

Total risk of exposure to IR (radiation workers)

Answer 12

400 per million exposed to 10mSv