On April 26, 1986, the worst commercial nuclear power plant disaster in history occurred with the explosion and fire at the Chernobyl No. 4 nuclear power plant in the Soviet Union. In terms of the amount of radioactivity released into the environment, the size of the affected area, long-term consequences, the numerous acute injuries, and 29 known deaths, the Chernobyl accident was the most significant nuclear event since the bombing of Hiroshima and Nagasaki.
Some elements of radiation physics, common sources of radiation (Table -1), the tissue effects of radiation, the signs and symptoms of radiation injury, and the evaluation and therapy of radiation injuries and exposure will be briefly covered in this chapter.

PATHOPHYSIOLOGY

Radiation may be classified as ionizing or nonionizing. Ionizing radiation is produced by nuclear weapons and reactors, radioactive material, and x-ray machines. The term ionizing is derived from the effect that such radiation produces when it interacts with matter, that is, it causes atoms to convert to ions as a result of the atoms’ loss or gain of electrons. Biological function may be affected if such ionized atoms are in the human body. On the other hand, light, radio waves, and microwaves are examples of nonionizing radiation.
Radiation is either particulate or electromagnetic. Electromagnetic radiation occurs in waveform and has no mass or charge. It belongs to a family of radiant energies that is described by wavelengths. Electromagnetic radiations, in order of decreasing energy content are ? rays, x-rays (photons), ultraviolet rays, visible rays, infrared rays, microwaves, and radio waves. Gamma waves and x-rays are electromagnetic radiations that can cause ionization. The electrons lost from atoms act as secondary particles and produce additional ionizations. X-rays differ from ? rays only in that x-rays are produced outside the nucleus of an atom; ? rays are emitted from the nucleus. Both travel great distances and readily penetrate body cells. X-rays and ? rays can easily be detected by Geiger-Muller (GM) counters.
Although ? and ? particles are not electromagnetic, they do cause ionization. The ? particle consists of two protons and two neutrons (identical to a helium atom without electrons) emitted from the nucleus of a high atomic number (?82) radioactive atom. The ??particles travel only a few centimeters in air and are completely stopped by paper or the keratin layer of the skin. The ? particle is an electron emitted from the nucleus of a radioactive atom. Beta particles travel up to a few meters in air but barely penetrate the skin. Both ? and ? particles are harmful, however, if they contaminate wounds or are ingested or inhaled. Contamination of the body surfaces by ? and ? particles can be detected by counters.
Energy deposited by radiation per unit of mass is referred to as the dose. A rad (radiation absorbed dose) is 100 ergs of energy deposited in 1 g of material. The Système International (SI) unit for dose is the Gray (Gy): 1 Gy ? 100 rad; 1 cGy ? 1 rad. The rem (roentgen equivalent man) is a calculated radiation unit of dose equivalent in which the absorbed dose in rad (or Gy) is multiplied by a quality factor to account for the biological effectiveness of different types of radiation. The SI unit for dose equivalent is the Sievert (Sv). 1 Sv ? 100 rem; 1 cSv ? 1 rem. We generally use the term rem or millirem (mrem) when referring to the exposure of biological systems. For x-rays, ? rays, and ? particles, the rad and the rem and the Gray and the Sievert are equivalent. A given rad dose from neutrons of ? particles produces up to 20 times as much biological damage as the same dose in rad from x-rays or ? rays. The whole body dose of ionizing radiation that will kill half of those who are exposed is approximately 400 rem (4 Sv). At about 600 rem (6 Sv) the mortality has been nearly 100 percent. Mental retardation has been associated with radiation doses as low as 5 rem to the fetus during the eighth to fifteenth week of gestation. The human average annual normal exposure to radiation in the United States from all sources, including radon, is approximately 360 mrem (3.6 mSv). A person or object exposed to radiation, other than high-dose neutron radiation, does not become radioactive. However, a person may be a risk to caregivers if contaminated with radioactive dirt or imbedded radioactive shrapnel, etc.
Equivalent doses received over a long time are less harmful than those received over a short period of time. For example, 100 rem (1 Sv) delivered over 1 year is much less harmful than 100 rem delivered in 1 s. The radiation dose from a point source of radiation decreases inversely as the square of the distance from the source.
The biological effects of radiation are a consequence of ionization. Free radicals are formed from water and can cause DNA and RNA strands to be broken. The most susceptible cells are those whose nucleic acids turn over most rapidly, i.e., cells of developing gametes, embryo, bone marrow, and the epithelium of the gastrointestinal tract. Cell and chromosomal changes may be minor and not pose a hazard to the organism. They may result in aberrations that are passed on to subsequent generations, or they may result in cell death, or the inability to replicate.

CLINICAL FEATURES

The most prominent systemic signs and symptoms of high [?100 rem (1 Sv)] whole body radiation exposure are malaise, nausea, vomiting, and diarrhea; seizures; erythema of the skin; and later, bleeding, anemia, and infection. Nausea and vomiting occasionally occur at about 100-rem exposure (Table -2). If they develop within 2 h of exposure, it suggests a dose of more than 400 rem (4 Sv); after 2 h from exposure, less than 200 rem (2 Sv); if none after 6 h from exposure, less than 50 rem (0.5 Sv). Erythema, local or generalized, indicates skin exposure greater than 300 rem (3 Sv); diarrhea indicates exposure of the gastrointestinal tract to greater than 400 rem (4 Sv); and seizures indicate central nervous system exposure greater than 2000 rem (20 Sv). Lymphocyte counts are useful prognostically. If after 48 h the lymphocyte count is ?1200/?L, the prognosis is good; 300 to 1200, fair; less than 300/?L, poor. Bleeding, anemia, and infection may occur after a latent period of 20 to 30 days.
Erythema and brawniness of the skin, indicating exposure of 300 or more rem (3 Sv), develop in a few hours and progress over days, just as with a thermal burn. While radiation burns are initially less painful than thermal burns, when pain does develop, and it often starts quickly, it may rapidly dominate the clinical picture. During circumstances in which fire as well as radioactive contamination may have occurred, ask the patient if he or she recalls exposure to fire or hot objects or caustic chemicals. Loss of hair, vesiculation, and ulceration may eventually develop if the radiation dose is high enough.
Following radiation exposure the likelihood of significant systemic effects can be estimated based on time of onset of nausea, vomiting, and diarrhea; changes in lymphocyte count; and knowledge of the accident, the radiation source, the dose readings at the site of the accident, and the duration of exposure.
Often a health physicist at the scene of an industrial accident is able to provide some indication of dose. Severity of symptoms varies and does not correlate with dose, but onset following exposure does. The earlier signs and symptoms develop, the higher the dose and the worse the prognosis. Initial symptoms (nausea, vomiting, and general malaise) generally subside within a few hours to several days and are followed by a latent period of 1 or more weeks. In general, if exposure is less than 125 rem (1.25 Sv), prognosis is good. For patients with doses less than 200 rem (2 Sv), probably nothing more than symptomatic treatment is needed, and recovery should occur. Those with exposure of 200 to 1000 rem should be promptly placed into a reverse isolation atmosphere. Further treatment need is probable to certain, and aggressive treatment can make a great difference in patient survival. Other than prompt external and internal body decontamination of radioactive material, and fluid replacement, when indicated, there is no emergency treatment specific to radiation exposure that will make any difference in long-term survival. Whatever symptoms occur should be treated symptomatically.
Following exposure to radiation, the exposed population is at risk for delayed complications such as leukemia and thyroid carcinoma. Contraception should be practiced for several months to avoid congenital defects in offspring.

TREATMENT

Initial treatment of radiation-exposed patients must first involve management of life-threatening injuries: airway impairment, bleeding, and circulation impairment. Patients who have been irradiated, that is, subjected to a high flux of ? rays or x-rays, are not radioactive. As such, no radiation is detected on the patient's body or clothes. Any tissue damage occurs instantaneously and will manifest itself in time. An irradiated person may sustain local or total body exposure. Following immediate management of life-threatening injuries, the patient should be checked with a GM counter for surface contamination, and it should be determined whether radioactive material has been ingested or inhaled. The GM counter is very useful for detecting ? and ? radiation. If used to detect ? radiation, it must contain a special window because of the low penetrating power of ? particles. In 1987, following the radiation accident in Goiania, Brazil, it was discovered that the axilla was the most representative point for measurement of dose rate using GM monitors in relation to internal cesium 137 body burden. Such an approach might be applicable when internal contamination with other whole body critical organ radionuclides is suspected. The health physicist at the site should be contacted so that data regarding dose, nature of exposure, type of radiation, and duration of exposure can be obtained.
Treatment protocol is as follows: Cover open wounds, remove the patient's clothing, and deposit contaminated material in closed receptacles. Protect open wounds to avoid contamination while washing or disrobing the patient. Next, wash the patient with soap and water. If the patient is on a drainage table, contaminated water can be collected in containers. If radioactive material in the form of solid particles, liquid, or dust is inhaled or ingested or contaminates an open wound, then incorporation has occurred. Since such material will irradiate internal tissues and may well cause extensive cellular damage, and since some radioactive elements may become permanently incorporated in the body's molecules, immediate treatment (decorporation) is indicated. Decorporation emphasis is directed at the gastrointestinal tract since even inhaled radioactive particulates tend to be coughed up and swallowed. Chelating agents provide an ion-exchange matrix that results in formation of an excretable stable complex containing the radioactivity. Radioactive actinide isotopes can be chelated effectively and subsequently excreted when diethylenetriaminepentaacetic acid (DTPA) is administered. Such action should be taken within 1 h of internal contamination. Chelating agents are useful only for transuranics and certain heavy metals. They would probably only be needed for accidents near a fuel-processing or military weapons facility. Although nuclear medicine departments may have stock DTPA solutions, they are too dilute to be useful as chelating agents for the removal of internal radioactive contamination. DTPA may be ordered from the Radiation Emergency Assistance Center/Training Site (REAC/TS) at Oak Ridge, Tennessee. If one anticipates the possible future need for DTPA, a request for current acquisition of it should be made to REAC/TS. DTPA is itself dangerous to use.
Primary wound closure is acceptable if successful decontamination is possible; however, if, in spite of irrigation and cleansing, a significant amount of contamination is retained in a wound, the wound should be left open for 24 h. Much of the remaining contamination will be freed up by bleeding and exudate and can then be removed by debridement. If an extremity is severely contaminated and adequate decontamination is not possible, the question of amputation may be raised. In general, unless the extremity is so severely traumatized that functional recovery is unlikely or unless contamination by radionuclides is so severe that extensive and severe radiation-induced necrosis can be expected, amputation is rarely indicated. The dictum is, decontaminate, but do not mutilate.
Though amputation is rarely required, one should aggressively debride and surgically decontaminate. Such procedures can usually be done without endangering a functional recovery. As surgical instruments become contaminated, they should be removed from the surgical field in order to prevent extension of contamination.
For contamination by plutonium or another long-lived ? emitter for which DTPA is an effective chelating agent, prompt treatment locally and intravenously is indicated, preferably prior to surgical decontamination.
Potassium iodide, a blocking agent, effectively prevents the uptake of radioactive iodine by the thyroid if it is given within a few hours of exposure. The National Council on Radiation Protection and Measurements recommends treatment to protect the thyroid when the dose is, or is expected to be, 10 to 30 rem. Persons 13 years of age or older should receive 130 mg of potassium iodide (100 mg stable iodine) by mouth daily for 14 days. However, pregnant women and children from 3 to 12 years of age should receive 65 mg potassium iodide (50 mg potassium iodine), and children under a year old, 32.5 mg potassium iodide (25 mg stable iodine) to minimize risk of side effects. Following the Chernobyl accident, 0.37 percent of Polish newborns who received potassium iodide prophylaxis on the second day of life showed transient increases in serum thyroid-stimulating hormone (TSH) levels and concomitant decreases in the serum free T4 levels. The transient thyroid inhibition had no sequelae. However, the findings indicate the need for careful observation in the event that more prolonged periods of treatment are indicated for infants. Antacids in the stomach precipitate many metals in the form of insoluble hydroxides, and can shorten the internal transit time of such material. Aluminum phosphate gel (100 mL) reduces the intestinal absorption of radioactive strontium by 85 percent, and barium sulfate precipitates radium.
A baseline complete blood cell count, differential blood cell count, and platelet count should be done during this initial treatment phase. For patients who have received ?200 rem, protective isolation is indicated, and blood transfusions may be necessary later. Bone marrow depression is usually evident 20 to 30 days after exposure. Appropriate cultures, antibiotic therapy as soon as there is evidence of infection, prophylaxis against fungal infections, and HLA typing of the patient and family members are all indicated in serious cases. Such supportive measures help to permit autologous bone marrow recovery, as does use of hemopoietic growth factors, when indicated. Bone marrow transplant may be considered if there is no recovery or if the stem cell pool is sufficiently damaged. Such damage would be evidenced by severe granulocytopenia, severe lymphopenia, and beginning thrymbocytopenia around day 5 to 7. These findings are evident when only 6 to 8 of every 10,000 stem cells have survived, i.e., irreversible stem cell damage.
Radiation burns are like electrical burns in that physical findings may be minimal initially. For ?-particle burns, excision followed by full-thickness grafting may be necessary.
Patients from a radiation accident scene may also have been exposed to chemical hazards. Thus, beryllium, which is present in many nuclear weapons, may be released as fumes and smoke, which in turn may cause respiratory distress, nervousness, and fever. Contamination of open wounds with beryllium results in greatly delayed wound healing. Treatment of the pulmonary problem includes, in addition to oxygen, ethylenediaminetetraacetic acid (EDTA) or another effective chelating agent.
When lead, used in nuclear weapon devices for shielding, burns it releases toxic fumes that can cause pneumonitis and dermatitis. Dermatitis and delayed-onset pneumonitis may also occur as a result of the inhalation of fumes from the combustion of plastics, which are used in most nuclear devices.
Finally, if a U.S. nuclear weapon were to accidentally detonate, such detonation would in all probability be incomplete. It would, however, be associated with blast effects, fires, and the spread of radioactive material. Unexploded pieces of the explosive might be scattered around an accident site. Such pieces frequently look like natural rock and should not be touched or moved unless absolutely necessary for evacuation of casualties.

DECONTAMINATION IN THE EMERGENCY DEPARTMENT

Advance notice of the arrival of a radiation-injured patient is important so that the emergency department can be prepared. Given such notice, emergency personnel can also advise on prior decontamination in the field.
Every nuclear facility must have identified primary and tertiary referral facilities. It is necessary to develop and maintain open channels of communication between the nuclear facility and the emergency department so that each will be prepared in times of individual injury or major accident. One should not rely on telephone communication being available within the hospital or between the hospital and other facilities in the event of a major nuclear accident or disaster. A predetermined plan involving backup radio communication is advised. Periodic exercises in which the facility is suddenly faced with the hypothetical need to treat a few or hundreds of irradiated and/or radioactive-contaminated patients is the best means to ensure the capability of dealing with such problems.
In the emergency department, a designated area, the radiation emergency area, isolated and preferably with a separate entryway, should be available for the management of patients with radiation exposure. Contamination should be prevented by covering the floor with plastic or paper sheets. Patients and personnel should be monitored for evidence of contamination. Personnel treating or attending the patient must be gowned and wear caps, masks, foot covers, double gloves, and personnel monitoring devices (i.e., film badge, thermoluminescent dosimeter badge, and/or pocket dosimeters). All personnel caring for patients suspected of contamination with radioiodine should, if possible, take potassium iodide prior to the arrival of the patient(s).
In rare cases it may also be necessary to provide a lead shield to protect personnel, especially in cases in which there are highly contaminated foreign bodies. Exposure can also be minimized by decreasing exposure time (several people would share care of a patient) and maintaining a distance from the patient whenever possible. Those providing care should not be exposed to more than 5 rem (0.05 Sv) except to save a life. The National Council on Radiation Protection has established that a once-in-a-lifetime exposure to 100 rem (1.0 Sv) for purposes of saving a life is acceptable and will result in no undue morbidity. Individuals not involved in the treatment should be kept away from the roped-off area. All attendant personnel should be monitored and decontaminated and their garments appropriately disposed of following completion of their involvement in the treatment process. Everyone working in the radiation emergency area must remain there, and traffic should never move in the reverse direction without first being appropriately monitored. Ambulance personnel and their vehicle(s) should also be checked for the presence of contamination before leaving the facility.

PREHOSPITAL DECONTAMINATION

R. E. Linnemann suggests an order of priority for treating a number of individuals involved in radiation accidents:
1. Injured and contaminated patients
2. Patients with certain types of internal contamination
3. Patients exposed only to external total body radiation
4. Patients exposed only to external local body radiation
If treatment of great numbers of radiation-exposed and contaminated patients is necessary, different modes may be indicated. Home treatment with showers or garden hoses should be considered, as should treatment at nearby facilities such as schools. An alternative decontamination facility within the hospital should be such that ready access and shelter available from fallout may be provided for a large number of contaminated patients. Triage should be performed to identify those who may require immediate medical care and/or decontamination. Those found to be contaminated should pass through a disrobing area and a shower, and ultimately be garbed with hospital gowns and reassessed for residual contamination. Again, resuscitation and stabilization always take precedence over decontamination.
Under these circumstances all available GM counters and dosimeters would be commandeered. Provision should be made for initial and follow-up treatment of any injuries. One should also consider establishing a large holding area, with subsequent transfer, if necessary, to other institutions where there is no area-wide radiation risk.

THE EVACUATION DILEMMA

Emergency physicians should be aware of the burden carried by local and state government officials who must make evacuation decisions. A population should be evacuated if the estimated per capita whole body radiation dose will be 50 rem (0.5 Sv) or more and seek shelter if the dose is expected to be 5 rem (0.05 Sv) or more. Emphasis is placed on predetermined actions for predetermined conditions. Thus, in a nuclear power plant accident if significant core damage has occurred, evacuation of the public from within a 2-mile radius is indicated. If the operator of the plant cannot assure the situation is under control, evacuation is indicated from within a 5-mile radius. If control is assured, all persons beyond 2 miles would be instructed to remain in available shelter. However, the present methods of dose assessment have a great range of uncertainty. The timing of a decision to evacuate may be crucial. Thus, officials fail if they wait too long, that is, until dangerous levels of radiation are present in populated areas, and they fail, too, if an unnecessary evacuation is ordered, for there are many risks inherent in an evacuation including adverse effects on moving hospitalized patients, panic reactions, and injuries and death from automobile crashes.

HOSPITAL EVACUATION

It is conceivable that internal hospital evacuation may be necessary in the event of radiation threat. Emergency radiation disaster plans should include designation of preselected sites within the hospital which afford the most protection for patients and health care personnel. Such sites are usually at ground level or below. Indeed, the dose can be increased by a factor of 10 or more if basement level is used. As much concrete as possible should be placed between personnel and the environment. Provision should be made for ensuring appropriate medical equipment, food, medications, and electric power and heat at the new care site (Table-3). Consideration should be given to shutting off fans and air conditioning during the critical exposure period (plume phase) and turning them back on following the plume phase in order to reduce exposure to radionuclides which have entered the building. The duration of such an internal evacuation would be related to the type of radiation and its half-life, atmospheric conditions, availability of supplies, and the condition of the patients.
External evacuation in the event of a radiation threat can be even more chaotic if not properly planned. One central source must provide for the evacuation needs of the hospitals in the area and determine the availability of off-site hospitals. Such an external evacuation would entail the need to categorize patients, effect discharge of ambulatory patients if possible, and provide clinical summaries plus radiographs and reports, a listing of medications and treatments needed, and a 24-h supply of food, water, and medications. Categorized patients would be taken to different and appropriate facility staging areas within the facility to await their external evacuation.

LESSONS LEARNED FROM CHERNOBYL

In the Three Mile Island incident, two workers received 3 to 4 (0.03 to 0.04 Sv) total body dose and several received ? radiation skin exposure of about 300 rem (3 Sv). No acute injury resulted in any of these cases. By contrast, 203 people were hospitalized and 29 died of radiation exposure as a result of the Chernobyl accident.
The lesson: build safe nuclear power plants. The Chernobyl No. 4 reactor, unlike U.S. nuclear power plants, contained a large mass of combustible material (2700 tons of graphite) and had much less contamination protection than do U.S. reactors.
A radiation disaster plan should include provision for (1) on-site triage; (2) a nearby hospital prepared for secondary triage, further decontamination, and treatment of life-threatening injuries; and (3) identified tertiary care radiation injury treatment centers to deal with contaminated injuries, including those of burn patients and patients in the advanced hematologic and immune system-suppressed states.
Based on the Chernobyl experience, most patients receiving less than 400 rem (4 Sv) whole body radiation can be expected to recover, if provided with optimal supportive care. Indeed, survival following a dose of 600 rem now appears possible.
The human immune system is vulnerable between 150 and 200 rem (1.5 and 2.0 Sv). At total body radiation exposures between 200 and 1500 rem (2 and 15 Sv), marrow damage is a major cause of death. And at higher doses, survival is limited by damage to skin, liver, lung, and gastrointestinal tract. At 5000 rem (50 Sv), death occurs in less than 2 days from central nervous system vasculitis.
Inhalation of particulate radioactivity can be significantly reduced (by a factor of 3 to 5) by breathing through several layers of moistened handkerchiefs, although the method is almost ineffective against gaseous radioiodines.
Emergency physicians might be faced with evaluating patients at times other than after acute exposure. In that context, the following points are important: granulocytopenic patients who develop fever require treatment with antibiotics, generally with those that cover enteric bacteria. Acyclovir is helpful in treating oral herpes simplex infection, which is apt to recrudesce following radiation exposure. If fever persists in a patient being treated with antibiotics, one should think of the possibility of systemic fungal infections and consider treating with amphotericin B.
Thermal burns and significant musculoskeletal and visceral injuries, if present, contribute significantly to radiation-related deaths. Physical radiation monitoring devices may prove inadequate, as they did at Chernobyl, in a nuclear accident. The devices may be destroyed, or they may not have been designed for the high levels of radiation encountered.
At Chernobyl biological dosimetry was used for dose assessment. Thus, serial measurements of granulocyte and lymphocyte levels as well as analyses of blood and bone marrow cell chromosomes for dicentrics, tricentrics, and rings were performed. In the case of cell chromosome analyses, the number of changes per cell is linearly related to exposures between 15 and 600 rem (0.15 and 6.0 Sv). The time elapsed between exposure and the onset of nausea and/or vomiting was also used for dose assessment purposes.
The world's ongoing need for nonfossil energy sources is borne out by the choices of other nations. The Japanese and Russians are adding significantly to their nuclear plant numbers, and the great majority of France's power generation is by nuclear plant.

SPECIAL ASPECTS OF RADIATION ACCIDENTS AND DISASTERS

In the absence of nuclear war or nuclear power plant disaster, such as occurred at Chernobyl, it is unlikely that most hospitals will receive any patients who have been involved in life-threatening radiation accidents. It is more likely that a given hospital's emergency department personnel will be called upon to handle a patient with routine injuries complicated by inadvertent radiation exposure or the presence of low-level radioactive contamination. Such a circumstance might result from an accident involving transportation of radioactive materials or a contaminating incident in a hospital's nuclear medicine department. Since radiation accidents are so uncommon, it is wise for emergency physicians to include in their planning discussions personnel from operating rooms, ICUs, and any other disciplines likely to be involved in the care of patients who have been exposed to and are contaminated with radioactive material.
Despite the Chernobyl accident, radiation injuries are an infrequent medical event, even though there are ever-increasing production and use of radiation-producing machines, radioactive products, nuclear plants, and nuclear weapons. Thus, as of 1988, worldwide there had been 69 peacetime deaths secondary to radiation exposure. And of these 69, nine were in the United States. No significant injuries or deaths due to radiation overexposure have occurred in the U.S. commercial nuclear power industry since its inception in 1957. The majority of industrial radiation accidents involve personnel radiated from high-activity sealed sources used in radiography. Nevertheless, as we plan for the more likely minor radiation accident, we must recognize that it is possible that the United States might sustain a terrorist attack with a nuclear weapon or suffer the accidental discharge and detonation of a nuclear weapon by another nation. An all-out exchange of thermonuclear weapons would not likely leave enough medical facilities and staff to provide an effective response, nor would any medical response under such conditions be apt to be sustainable.
Whatever the basis for a radiation accident or disaster, prior communication, instruction, and staff exercises are the best preparation for any eventuality. As a corollary, ongoing communication with staff during an exercise or real life accident or disaster is a must. The role of the public relations department is very important, for it is such personnel who, under such circumstances, deal with the media and the public.
In addition to your own staff and others who are experienced and knowledgeable about radiation, there are other individuals and organizations, private, state, and federal, willing and able to promptly respond to your call for aid. Finally, nuclear facilities do not “blow up” like nuclear bombs. It is physically impossible. Instead, a nuclear plant accident is more apt to be associated with a potentially large number of people being slightly exposed, slightly contaminated, and very anxious.

BIBLIOGRAPHY:

1)Linnemann RE: Medical experience and preparedness for handling radiation injuries. J Med Assoc Georgia 78:95, 1989.
2)Nauman J, Wolff J: Iodide prophylaxis in Poland after the Chernobyl reactor accident: Benefits and risks. Am J Med 94:524, 1993.
3)Oliveira A, Hunt J, Valverde N, et al: Medical and related aspects of the Goiania accident: An overview. Health Phys 60:17, 1991.
4)Perry AR, Iglar AF: The accident at Chernobyl: Radiation doses and effects. Radiotechnol 61:290, 1990.
5)Task Group of Committee 4 of the International Commission on Radiological Protection: Principles for intervention for protection of the public in a radiological emergency. Ann ICRP 22:1, 1991.
6)Weinsheimer W, Szepesi T, Fliedner TM: Early indicators of response to accidental radiation exposure and relevance for clinical management strategies. Prog Clin Biol Res 372:155, 1991.

TABLE
Common Sources of Radiation

Whole Body,
Source mrem/yr Dose Rate

Natural sources:
Radon 200
Natural background
radiation 35
Air 5
Building materials 34
Food 25
Ground 11
Medical 50
Total 360
Technological sources:
Coast-to-coast jet flight 5 mrem/round trip
Color television 1 mrem/yr
AP chest film 10 mrem/film

TABLE
Dose-Effect Relations Following Acute Whole Body Irradiation (X- or ?-Ray)
Whole Body
Dose, rad Clinical and Laboratory Findings

5–25 Asymptomatic. Conventional blood studies are nor-
mal. Chromosome aberrations detectable.
50–75 Asymptomatic. Minor depressions of white cells and
platelets detectable in a few persons, especially if
baseline values established.
75–125 Minimal acute doses that produce prodromal symp-
toms (anorexia, nausea, vomiting, fatigue) in about
10–20% of persons within 2 days. Mild depressions
of white cells and platelets in some persons.
125–200 Symptomatic course with transient disability and clear
hematologic changes in a majority of exposed per-
sons. Lymphocyte depression of about 50% within
48 h.
240–340 Serious, disabling illness in most persons with about
50% mortality if untreated. Lymphocyte depression
of about??75% within 48 h.
500+ Accelerated version of acute radiation syndrome with
GI complications within 2 weeks, bleeding, and
death in most exposed persons.
5000+ Fulminating course with cardiovascular, GI, and
CNS complications resulting in death within 24–72 h.

TABLE
Emergency Supplies for Use in Radiation Emergencies

Radiation detection instruments including Geiger-Müller counters, spare
batteries, film badges, ring badges, self-reading dosimeters
Surgical scrub suits
Surgical gowns
Surgical caps
Surgical masks
Surgical gloves
Plastic shoe covers
Adhesive tape
Plastic sheets and bags
Step-off pads
Plastic containers for collection of decontamination fluids
Decontamination stretcher
Roll of plastic floor covering for use in the hallway
Radiation “mark off” rope
Radioactive signs and labels
Filter paper for smears
Clipboard, paper, and pens
Assorted containers for sample collection