Late effects of radiation

Question 1

What are these outcomes called and what are they the result of?

Radiation-induced damage at the cellular level may lead to measurable somatic and genetic damage in the living organism as a whole later in life.

Answer 1

These outcomes are called late effects and are the long-term results of radiation exposure.

Question 2

How long does it take for a late effect to show up?

Answer 2

Months to years after exposure

Question 3

What might a late effect result from?

Answer 3

1. Previous whole- or partial-body acute exposure
2. Previous high radiation doses:
3. Long-term low-level doses sustained over several years

Question 4

T/F

Late effects come from cells that are damaged but live

Answer 4

True

Question 5

T/F

Most stochastic effects and genetic effects at low dose levels from low-LET radiation, appear to follow a non-linear, threshold curve.

Answer 5

False; Most stochastic effects and genetic effects at low dose levels from low-LET radiation, appear to follow a linear non-threshold curve.

Question 6

What relationship is this talking about?

Information obtained can be used to attempt to predict the risk of occurrence of malignancies in human populations that have been exposed to low levels of ionizing radiation.

Answer 6

Dose response relationship

Question 7

What is a Non-stochastic Late Effect?

Answer 7

Late effects that can be directly related to dose received

Question 8

What is a Stochastic late effect?

Answer 8

Late responses that do not have a threshold

Question 9

What are 4 examples of Non-stochastic Late Effects?

Answer 9

1) cataracts
2) sterility
3) fibrosis
4) atrophy

Question 10

What are 2 examples of stochastic late effects:

Answer 10

1) Cancer
2) embryologic effects

Question 11

What dose in Gy can induce cataracts?

Answer 11

2 Gy will induce the formation of cataracts.

Question 12

What is the DL for the lens of the eye?

Answer 12

150 mSv

Question 13

What is the result of cataracts?

Answer 13

Partial or complete loss of vision

Question 14

T/F

The formation of cataracts is a nonlinear dose-response relationship

Answer 14

True

Question 15

What is the amount of radiation (low diagnostic amount) that could possibly cause cancer?

Answer 15

Could be caused by doses above .5mSv

Question 16

What are Genetic Effects of radiation?

Answer 16

Stochastic effects from damaged genes

Question 17

What is the most effective mutagen?

Answer 17

Ionzing radiation

Question 18

T/F

Even a non-lethal dose to a germ cell can create genetic mutations which can be passed to successive generations

Answer 18

True

Question 19

What are the natural mutations that frequency can be increased with ionzign radiation?

Answer 19

Huntingtons, Down syndrome, Duchenne muscular dystrophy, Cystic fibrosis

Question 20

What are the two types of germ cell mutations?

Answer 20

1.Dominant mutation
2.Recessive mutations

Question 21

T/F

Genetic mutations are threshold.

Answer 21

False; Genetic mutations are non-threshold

Question 22

What do recessive mutations require in order to be expressed?

Answer 22

Requires a mutated gene from both parents

Question 23

What do dominant mutations require in order to be expressed?

Answer 23

Only requires a mutated gene from one individual

Question 24

T/F

GE’s or hereditary effects do not have a threshold

Answer 24

True

Question 25

T/F

Ionizing radiation is thought to cause primarily dominant mutations

Answer 25

False; Ionizing radiation is thought to cause primarily recessive mutations

Question 26

Damage from recessive mutation may appear as what?

Answer 26

Allergies, alteration on metabolism, decreased intelligence, predisposition to certain diseases

Question 27

T/F

Currently there is evidence of radiation induced hereditary effects in diagnostic imaging workers and their patients

Answer 27

False; Currently there is no evidence of radiation induced hereditary effects in diagnostic imaging workers or their patients

Question 28

What concept is this reffering to?

It is the radiation dose that causes the number of spontaneous mutations occurring in a given generation to increase to two times their original number.

Answer 28

Doubling dose concept

Question 29

What is the radiation doubling equivalent dose for humans?

Answer 29

1.56 Sv