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6 Health Effects of Radiological Weapons
6.3 Special Considerations for Those Near an Explosion
Explosions are dangerous—this should go without saying. Explosions injure and
kill people through the pressure wave they produce, by propelling shrapnel and other
objects at high speed, by causing structures to collapse, and so forth. In addition
to these a “dirty bomb” can also expose people to radiation, radioactivity blasted
into the air can be inhaled or ingested, radioactive fragments or pieces of radioactive
sources can be driven into flesh, and radioactive contamination can enter open cuts
or wounds.
6.3.1 Ingested or Inhaled Radioactive Materials
Inhaling or ingesting radioactivity can result in a high radiation dose because, when
radioactive materials enters the body, exposure continue as long as the radioactivity
is present. All else being equal, inhaled radioactivity tends to produce a higher dose
than when the material is ingested because materials in the digestive tract are typically
present for only one or two days before the materials are eliminated and anything
not absorbed into the body during this time will be excreted. On the other hand,
materials in the lungs might remain there for weeks or months if the particles are
inhaled deeply into the lungs—such particles might either dissolve totally into the
body fluids and will continue irradiating the tissues of the lungs until they dissolve.
Once the radioactivity had entered the bloodstream it will circulate through the
body according to its chemical properties. Strontium, radium, and plutonium (for
example) will be taken up by the bones and will remain there for the remainder of
the person’s life, cesium will behave similarly to potassium and will pass out of the
body relatively quickly, iodine will be taken up by the thyroid and will remain there
for several weeks while iodine in the blood will be quickly excreted. Understanding
the biokinetics of the radionuclide(s) inhaled or ingested is crucial to understanding
the long-term radiation dose the person will receive [6].
For those who have ingested or inhaled radioactivity it will be important to quickly
assess the approximate radiation dose to be expected; this can be quickly performed
using hand-held radiation instruments (e.g. [3]), by making more precise (albeit more
time-consuming) bioassay measurements [7], or by assessing a person’s medical
condition as their symptoms unfold [11]. If this assessment indicates that a person
has ingested or inhaled a potentially damaging amount of radioactivity it is frequently
possible to hasten the removal of this radioactivity from the body using an appropriate
decorporation agent [7] to reduce radiation exposure. As one example, following the
radiation accident in Goiania Brazil the use of potassium ferrocyanide (colloquially
known as Prussian blue) was noted to reduce the biological residence time (and
concomitant radiation dose) by as much as 43% [9]. Although there are not decorporation agents available for every known radionuclide, they are available for a large
number of elements in various chemical forms.
6 Health Effects of Radiological Weapons
6.3 Special Considerations for Those Near an Explosion
Explosions are dangerous—this should go without saying. Explosions injure and
kill people through the pressure wave they produce, by propelling shrapnel and other
objects at high speed, by causing structures to collapse, and so forth. In addition
to these a “dirty bomb” can also expose people to radiation, radioactivity blasted
into the air can be inhaled or ingested, radioactive fragments or pieces of radioactive
sources can be driven into flesh, and radioactive contamination can enter open cuts
or wounds.
6.3.1 Ingested or Inhaled Radioactive Materials
Inhaling or ingesting radioactivity can result in a high radiation dose because, when
radioactive materials enters the body, exposure continue as long as the radioactivity
is present. All else being equal, inhaled radioactivity tends to produce a higher dose
than when the material is ingested because materials in the digestive tract are typically
present for only one or two days before the materials are eliminated and anything
not absorbed into the body during this time will be excreted. On the other hand,
materials in the lungs might remain there for weeks or months if the particles are
inhaled deeply into the lungs—such particles might either dissolve totally into the
body fluids and will continue irradiating the tissues of the lungs until they dissolve.
Once the radioactivity had entered the bloodstream it will circulate through the
body according to its chemical properties. Strontium, radium, and plutonium (for
example) will be taken up by the bones and will remain there for the remainder of
the person’s life, cesium will behave similarly to potassium and will pass out of the
body relatively quickly, iodine will be taken up by the thyroid and will remain there
for several weeks while iodine in the blood will be quickly excreted. Understanding
the biokinetics of the radionuclide(s) inhaled or ingested is crucial to understanding
the long-term radiation dose the person will receive [6].
For those who have ingested or inhaled radioactivity it will be important to quickly
assess the approximate radiation dose to be expected; this can be quickly performed
using hand-held radiation instruments (e.g. [3]), by making more precise (albeit more
time-consuming) bioassay measurements [7], or by assessing a person’s medical
condition as their symptoms unfold [11]. If this assessment indicates that a person
has ingested or inhaled a potentially damaging amount of radioactivity it is frequently
possible to hasten the removal of this radioactivity from the body using an appropriate
decorporation agent [7] to reduce radiation exposure. As one example, following the
radiation accident in Goiania Brazil the use of potassium ferrocyanide (colloquially
known as Prussian blue) was noted to reduce the biological residence time (and
concomitant radiation dose) by as much as 43% [9]. Although there are not decorporation agents available for every known radionuclide, they are available for a large
number of elements in various chemical forms.