Module 2 Biological Effects
Tobacco products (total average dose ~1300 mrem/yr
Medical radiation sources (total average dose ~ 54
1) X rays (total average dose ~ 40mrem/yr)
a) X rays are similar to gamma rays; however, they
originate outside the nucleus.
b) A typical radiation dose from a chest
X ray is about 10
Diagnosis and therapy (total average dose ~14 mrem/yr)
In addition to X rays, radioactive materials and
radioactive sources are used in medicine for diagnosis
c. Building materials (total average dose ~7 mrem/yr)
Discuss: It has been more
Other minor contributors
than 20 years since
atmospheric testing has been
Other contributors to dose include consumer products,
industrial sources, and atmospheric testing of nuclear
EO2 Identify the average
Average annual dose
annual dose to the general
population from natural
The average annual total effective dose equivalent to the
general population (non-smokers) from naturally
background and manmade
occurring and manmade sources is about 360 mrem.
sources of radiation.
Effects of Radiation on Cells
The human body is made up of many organ systems. Each
system is made up of tissues. Specialized cells make up
tissues. Ionizing radiation can potentially affect the normal
function of cells.