Pediatric emergency medicine trisk 1985 1985
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radioactive materials is accomplished by treating the patient in a single location,
controlling access to that location, and by using standard contact precautions.
Internal contamination. Internal contamination can be a serious problem
because it is difficult to eliminate some long-lived radioactive materials from
within the body. Death due to radiation from internal contamination is rare. A few
deaths have been caused by medical misadministrations. A familiar example of
intentional, nonlethal internal contamination is the bone scan performed in a
nuclear medicine department. Treatment of hyperthyroidism with 131I
(radioactive iodine) also is, in a sense, planned internal contamination.
Metal fragment. Another source of possible contamination is the radioactive
metallic fragment, which can be intensely radioactive. These could, in principle,
be found if a “dirty bomb” was constructed with a radioactive metal source such
as 192Ir (radioactive iridium). Radioactive metal fragments can be embedded in
the patient’s skin and should never be touched with the examiner’s fingers. Tongs
or forceps will increase the distance between the radioactive metal fragment and
the fingers, and thus greatly reduce any radiation dose to the healthcare worker.
Hot particles. “Hot” particles are microscopic particles that can be highly
radioactive. Typically, they contain 60Co (radioactive cobalt) or other fission
products and might be found on a nuclear reactor worker after a reactor accident.
These particles can be difficult to localize and remove and may give a large
radiation dose to a small volume of tissues. If the particle is trapped under a nail
or is in the fold of the skin, routine washings may not dislodge it. The particle can
sometimes be localized by using a thick piece of lead. If the lead is placed
between the particle and the radiation detector, the exposure rate should decrease
substantially. Once the particle is localized, it can usually be removed by using
simple mechanical means. Rarely, a punch biopsy of the skin may be necessary.
Terrorist events. Nuclear materials may be used intentionally in a terrorist
event. An intact sealed source could be placed in a populated area, generating
whole-body exposures but no contamination. A conventional explosive combined
with radioactive materials, the so-called “dirty bomb,” could be employed to
disseminate radioactive materials over an area. Victims of such an attack would
likely have radiation exposure as well as injuries from the explosion itself. An
attack on a research or commercial power reactor could produce a large-scale
dispersion of nuclear material; victims could be exposed to whole-body and
localized radiation, as well as internal and external contamination. Transported
nuclear materials such as radiopharmaceuticals or radioactive waste could be the
subject of a terrorist attack. The effects would vary depending on whether the
containers were breached—intact containers would produce only potential
