Lesson 10: Late Effects of Radiation

Question 1

Define Principles of Late Effects of Radiaton

Answer 1

• long term effects of radiation exposure
• previous or whole body exposure
• previous high radiation doses
• long term low level doses
• caused from cells that are damaged but live

Question 2

Where are most stochastic effects from

Answer 2

low dose levels at low LET radiation
- follow a linear non threshold curve

Question 3

Major Types of Late Somatic Effects

Answer 3

Non-Stochastic Late Effects: Late effects that can be directly related to dose received
Stochastic: Late responses that don’t have a threshold

Question 4

Give Examples of non stochastic Late Effect

Answer 4

• cataracts
• sterility
• firbosis

Question 5

Give Examples of Stochastic Late Effects

Answer 5

• cancer
• embryologic effects

Question 6

3 Major Types of Late Effects of Radiation

Answer 6

• cataracts
• cancer
• birth defects

Question 7

What type of effect is cataracts

Answer 7

• deterministic
• 2Gy will introduce formation
• latent period/chronic exposure= 15 years

Question 8

Possible Effects of Low Diagnostic Level Radiation

Answer 8

• No conclusive proof that doses
  below 0.1 Sv (10 REM) have a
  significant risk
• Low level radiation from: xrays and
  radioactive material (diagnostic
  procedures), employment related
  exposures, natural background
• cancer induction, genetic effects

Question 9

Where does the current understanding of the Effects of radiation come from

Answer 9

• watch dial painters
• uranium miners
• early radiation workers
• Chernobyl

Question 10

Where do genetic Effects come from

Answer 10

• stochastic effects from damaged genes
• ionizing radiation can increase the frequency of genetic mutations

Question 11

Where does the evidence of genetic effects come from

Answer 11

• fruit flies and mice
• radiation can cause recessive or dominant mutations

Question 12

What kind of genetic effects does radiation produce

Answer 12

• recessive
• rare but not likely to appear in population at diagnostic level

Question 13

What is dose doubling concept

Answer 13

• doubling the radiation dose that causes the number of spontaneous mutations occuring in a given generation to increase 2 times their original numbers

Question 14

What significance does mutations have to a population

Answer 14

• leads to elevated health costs due to disease
• leads to a possible change in the gene pool, more reccessive diseases present
• must minimzie genetically significant dose (ALARA)