Biomedical Engineering Reference
In-Depth Information
radiological event and the possibility that terror-
ists may attempt to attack such facilities has led
to the implementation of more stringent security
measures at nuclear facilities.
While the traumatic effects of blast and thermal
injury are visible and tangible, the effects of radi-
ation are not directly apparent and can only be
discerned by the secondary effects. This is evident
in the aftermath of the effects of the nuclear acci-
dent that took place in Chernobyl on 26 April
1986. On that day, an explosion secondary to
loss of cooling capacity destroyed the nuclear
reactor at Chernobyl. This explosion sent a cloud
of radioactive material and gases 1 km high. Two
workers died as a direct effect of the explosion.
Those that remained in shielded areas of the plant
survived while some of those that went to fight
the fires died of radiation effects. Sources of radi-
ation exposure in this catastrophe came from the
short-term gamma/beta emissions in the explosion
and the subsequent gamma/beta radiation from the
reactor core debris. Because of a lack of water-
proof protective clothing and respirators, another
principal source of radiation was from the deposi-
tion of particulate matter on the skin and mucous
membranes of personnel in the area. The primary
sources of residual radiation were due to iodine
131, strontium 90, and cesium 137 [1,2]. During
the acute event in this low population density
area, 29 casualties were evaluated in the first 30
minutes. In the next 24 hours, 140,000 people were
evacuated from the 30 km surrounding Chernobyl
and potassium iodate tablets distributed. Over the
next few weeks 230 patients were hospitalized
with priority given to those with early onset of
nausea and vomiting, skin and mucous membrane
radiation burns and a decrease in the lymphocyte
count to less than 1000/mm
3
. Infectious disease
therapy consisted of standard regimens for the
neutropenic patients. Bone marrow transplantation
was attempted in 19 patients receiving >6Gy irra-
diation. However, this did not seem promising,
as 17 of 19 died due to the associated radi-
ation burns. All told, radiation burns (40-90%
BSA) contributed to the deaths of 21 patients.
In addition, 82 patients had respiratory difficulty
secondary to oropharyngeal radiation burns. Over
the next 4 years, the average radiation exposure
around Chernobyl was 4 times the normal. This
was primarily due to residual ground contamina-
tion with cesium 137. Despite the relatively low
number of acute casualties given the magnitude
of the accident, the long-term impact predicts an
additional 24,000 cancers in Europe and 280 in the
region around Chernobyl [3-5].
The worst scenario, and the least likely, is a
terrorist organization diverting an existing nuclear
device or procuring enough material and expertise
to manufacture a nuclear device. In this scenario
a terrorist group could try to purchase a nuclear
weapon, as the Japanese Aum Shinrikyo cult tried
to do in Russia, or build a crude device on its
own and utilize ground or ship transport to deliver
the weapon to the point of detonation. Evidence
suggests that some groups, including the Al-Qaeda
network, have attempted to obtain weapons grade
nuclear material. Since 1993, there have been 175
cases of trafficking in nuclear material; 18 of
which involved substantial quantities of weapons
grade material. After acquiring fissionable nuclear
material, sophisticated terrorists could design and
fabricate a workable atomic bomb. The wake of
a nuclear terror attack would be large numbers
of casualties with combined injuries generated
from the periphery of the lethal zone. Infrastruc-
ture, economic centers, and communications would
be destroyed or disrupted by the electromagnetic
pulse. The large numbers of fatalities and casual-
ties in conjunction with the psychological effects
and long-term radiation effects would impose a
massive burden on available medical facilities.
For example, a relatively small nuclear device of
15-kilotons detonated in Manhattan could immedi-
ately kill upwards of 100,000 inhabitants, followed
by a similar number of deaths afterward. In addi-
tion, advanced medical care would be available
only outside the area of immediate destruction and
contamination. Consequently, the primary manage-
ment importance would be placed on early evacua-
tion of casualties to other available medical centers
throughout the United States.
Because of the unique nature of radiological
injury,
the theory and treatment of
radiolog-
ical casualties is taught
in the Medical Effects
