Chapter 3
Health Effects of Radiation
Radiation frightens many people and the primary reason for this fear is their anxiety
about radiation’s health effects. Popular culture accounts of radiation exposure tend
to show dramatic injuries, burns, suffering, and death—all things that most people
prefer to avoid. In addition, we read about the effects of in utero radiation exposure—
causing birth defects for example—as well as long-term effects such as cancer. With
all of this, it is hardly surprising that people tend to be frightened of radiation.
The bad news is that radiation can, indeed, cause many of the health effects that
worry people so much. The good news is that it takes far more radiation exposure to
cause these effects than most people believe.
3.1 Radiation Effects on the Cell
Radiation can damage cells by directly striking the DNA and causing damage such
as single- or double-strand breaks or point mutations. It’s more likely, however,
that the radiation will strike molecules in the cytoplasm, interacting with them and
forming free radicals (molecules that are very chemically active) that go on to cause
DNA damage. Free radicals are generated by any of a number of mechanisms—
mitochondria leak free radicals for example, metabolizing our food can create free
radicals, and so forth. Not only that, but the DNA damage caused by any of these
factors appears to be largely the same; in other words, we can’t “look” at a point
mutation and tell if it was caused by radiogenic or mitochondrial free radicals.
When radiation passes through a cell the effects can be non-existent, profound or
anything in between. Sometimes a gamma ray will pass right through a cell without
interacting at all and sometimes the free radicals produced will recombine or be scavenged before they can reach the DNA. If radiation (or the free radicals is produces)
does interact with the DNA then either the DNA will be damaged or it won’t. If
the DNA is damaged, that damage may be beneficial, harmful, or neutral (neutral
© Springer Nature Switzerland AG 2021
P. A. Karam, Radiological and Nuclear Terrorism,
Advanced Sciences and Technologies for Security Applications,
https://doi.org/10.1007/978-3-030-69162-2_3
21
Health Effects of Radiation
Radiation frightens many people and the primary reason for this fear is their anxiety
about radiation’s health effects. Popular culture accounts of radiation exposure tend
to show dramatic injuries, burns, suffering, and death—all things that most people
prefer to avoid. In addition, we read about the effects of in utero radiation exposure—
causing birth defects for example—as well as long-term effects such as cancer. With
all of this, it is hardly surprising that people tend to be frightened of radiation.
The bad news is that radiation can, indeed, cause many of the health effects that
worry people so much. The good news is that it takes far more radiation exposure to
cause these effects than most people believe.
3.1 Radiation Effects on the Cell
Radiation can damage cells by directly striking the DNA and causing damage such
as single- or double-strand breaks or point mutations. It’s more likely, however,
that the radiation will strike molecules in the cytoplasm, interacting with them and
forming free radicals (molecules that are very chemically active) that go on to cause
DNA damage. Free radicals are generated by any of a number of mechanisms—
mitochondria leak free radicals for example, metabolizing our food can create free
radicals, and so forth. Not only that, but the DNA damage caused by any of these
factors appears to be largely the same; in other words, we can’t “look” at a point
mutation and tell if it was caused by radiogenic or mitochondrial free radicals.
When radiation passes through a cell the effects can be non-existent, profound or
anything in between. Sometimes a gamma ray will pass right through a cell without
interacting at all and sometimes the free radicals produced will recombine or be scavenged before they can reach the DNA. If radiation (or the free radicals is produces)
does interact with the DNA then either the DNA will be damaged or it won’t. If
the DNA is damaged, that damage may be beneficial, harmful, or neutral (neutral
© Springer Nature Switzerland AG 2021
P. A. Karam, Radiological and Nuclear Terrorism,
Advanced Sciences and Technologies for Security Applications,
https://doi.org/10.1007/978-3-030-69162-2_3
21