Module 2: Biological Effects
2. Phone Number
B. Module Overview
has been known for many years. We have gained most of
our knowledge of these effects since World War II.
In this module, we will discuss the potential for biological
effects and risks due to ionizing radiation and put these
potential risks into perspective when compared to other
occupations and daily activities. With this information, it is
hoped that employees will develop a healthy respect for
radiation rather than fear or disregard.
C. Objectives Review
We know more about the biological effects of ionizing
radiation than most other environmental factors. Rather than
just being able to base our information on animal studies, we
have a large body of information available regarding
exposures to humans. There are four major groups of people
that have been exposed to significant levels of radiation.
The first group includes early radiation workers, such as
radiologists. These workers received large doses of radiation
before the biological effects were recognized. Since that time,
standards have been developed to protect workers.
The second group is the more than 250,000 survivors of the
atomic bombs dropped at Hiroshima and Nagasaki. Some of
these survivors received doses estimated to be in excess of
The third group includes individuals who have been involved
in radiation accidents.
The fourth and largest group of individuals are patients who
have undergone radiation therapy for cancer and other