Post on 07-Jan-2016
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Getting Prepared for a Radiological Terrorist Event
David J. Brenner, Ph.D., D.Sc.,Center for Radiological ResearchColumbia University Medical Centerdjb3@columbia.edu
You can view / download this lecture at www.columbia.edu/~djb3
Goiânia, Brazil, 1987Population 1.3 million
Abandoned medical clinic in Goiânia contained 1,400 Curie radioactive cesium sources
The radioactive sources were stolen, broken open, and dispersed
Goiânia incident: Equivalent to large-sized dirty-bomb scenario in Manhattan
• 130,000 people (10%) came to ER / temporary screening locations
• 250 (0.2%) were contaminated
• 20 (0.01%) required treatment
Topics that we will cover
What is ionizing radiation?What is ionizing radiation?How is it harmful?How is it harmful?
Radiation threat scenarios Radiation threat scenarios
Appropriate medical responsesAppropriate medical responses
Psychological aspectsPsychological aspects
ResourcesResources
Radioactivity
The spontaneous emission of radiations: alpha rays, beta rays, gamma raysfrom radioactive materials
Radioactivity: Alpha Rays
Radioactivity: Beta Rays
Radioactivity: Gamma Rays
The Electromagnetic Spectrum
Interaction of alpha, beta, gamma rays with matter:
Ionization
Alpha, beta and gamma rays
Radiation vs. Radioactive Material
• Radiation: energy transported in the form of particles or waves (alpha, beta, gamma, neutrons)
• Radioactive Material: material that contains atoms that emit radiation spontaneously
Exposure vs. Contamination
External Exposure: irradiation of the body from external source
Contamination: radioactive material on patient (external) or within patient (internal)
Radiation Dose
• Measured in milliGray (mGy) (1/1000 joule / kg)
• Equivalent dose is measured in milliSievert (mSv)
• For our purposes, 1 mGy = 1 mSv
• Old units are the rad and the rem
• 10 mGy = 1 rad; 10 mSv = 1 rem
• Average background radiation dose is 3 mSv / yearA mammogram produces about 0.01 mSv.A CT scan produces about 10 mSv.
Radioactivity
• The activity (strength) of a radioactive source is measured inCuries (Ci) or Becquerels (Bq)
• 1 Bq = 1 radioactive disintegrations / sec
• 1 Ci = 37 GBq
= 37 thousand million disintegrations / sec
The Principal Hazards ofIonizing Radiation
Cancer risks
Hereditary risks
Effects on the developing embryo/fetus
Radiation Risks
Teratogenic risks
Order of magnitude larger than
Carcinogenic risks
Order of magnitude larger than
Hereditary risks
The Carcinogenic Effects of Ionizing Radiation
Ionizing Radiation and Cancer
Most of our information Most of our information comes from studies ofcomes from studies ofA-bomb survivorsA-bomb survivors
Lifetime cancer mortality risk as a function of age at exposure
Individual Susceptibility to Radiation Carcinogenesis
There are likely to be subpopulations of individuals who are significantly more sensitive to ionizing radiation than the average:
• Children• ATM heterozygotes
(Ataxia Telangiectasia, 1-2% of the population)• BRCA1• BRCA2
Radiation-induced hereditary effects
RRadiation does not produce new, unique mutations, but simply increases the incidence of the same mutations that occur spontaneouslyspontaneously
Teratogenic Risks(i.e., to the embryo/fetus, if relevant)
Moderate doses of radiation can produce catastrophic effects on the developing embryo and fetus.
Growth retardation
Embryonic, neonatal, or fetal death
Congenital malformations and functional impairment,such as mental retardation.
The principle effects of radiation on the developing embryo and fetus are:
Radiation Risks
Teratogenic risks
order of magnitude larger than
Carcinogenic risks
order of magnitude larger than
Hereditary risks
Radiation Threat Scenarios
Nuclear device
Damage to nuclear power plant
Dirty bombs
Nuclear DeviceRisk• Exposure to rays and neutrons
• Fallout of fission products (including short-lived iodine isotopes)
Outcome• Large number of acute deaths
• Long-term carcinogenesis
Likelihood • Remote
Attack on a nuclear power plant
Risk• Attack on the reactor itself:
• Attack on stored used fuel elements
Release of fission products: I-131, Cs-137, etc
Outcome• Unlikely to involve acute deaths
• Long-term carcinogenesis
Likelihood • Extremely unlikely
Dirty Bombs (Radioactive dispersal devices, RDD)
Risk• Release of radioactive cesium, cobalt or americium
• Small number of contaminated people
• Large number of very slightly contaminated people
• Psychological chaos (many frightened people)
Outcome• Unlikely to result in acute deaths
• Risk of long-term carcinogenesis
Likelihood • Likely
Radioactive material
Conventional explosive(e.g. fertilizer, semtex)
Time fuse
Detonator
Radioactive Dispersal Device (RDD)
Dirty Bombs
How available are the radioactive materials?
August 1994
Three people arrested at Munich airport having flown on a Lufthansa flight from Moscow carrying 363 grams of plutonium
November 1995
Moscow, Russia -- A group of Chechen rebels contacts a Russian TV station to claim that they have buried a cache of radiological materials in Moscow's Ismailovsky Park.
There, the authorities find a partially buried container of radioactive cesium.
December 1998
Argun, Chechnya – A container filled with radioactive materials found attached to an explosive mine hidden near a railway line. It is safely defused.
The location is Argun, near the Chechen capital of Grozny, where a Chechen group, led by Shamil Basayev, operated an explosives workshop.
June 2002
Chicago, Illinois -- Jose Padilla, a US citizen with links to Al Qaeda, is arrested in Chicago airport on suspicion of planning to build and detonate a dirty bomb.
F.B.I agents suspect Padilla had recently undergone training in Pakistan, where he allegedly studied the mechanics of dirty-bomb construction, including how to wire explosive devices and how to optimize bombs for radiological dispersion.
January 2003
A collage of dirty bomb plans journalists recently discovered in Afghanistan
Herat, Afghanistan -- Based on evidence uncovered in Herat, including detailed diagrams and computer files, British intelligence agents conclude that Al Qaeda has succeeded in constructing a small dirty bomb, though the device has not been found.
March 1998
Cesium tubes similar to the ones missing from Greensboro
Greensboro, North Carolina -- Nineteen small tubes of cesium are taken from a locked safe in Moses Cone Hospital. The total activity was 22 Gbq (0.6 Ci).
Each tube was three-quarters of an inch long by one-eighth of an inch wide and were used in the treatment of cervical cancer. The cesium is never recovered.
March 2002Nucor Steel Mill, Hertford, NC
2 Ci cesium industrial gauge found on scrap metal conveyer belt
Traced back to a batch of four belonging to a bankrupt Baltimore chemical company. Three have been located....
Moisture Density Gauges, contain small quantities of americium-241 and cesium-237
About 22,000 in use in the US. About 50 per year reported as missing
August 2004
London: Islamic terrorist cell, led by Dhiren Barot, raided. Large cache of household smoke detectors found, each containing small quantities of americium-241
Small and large dirty bombs (RDD: Radioactive dispersal device)
Small RDD:High explosives dispersing 0.1 to 10 Curies
Intermediate RDDHigh explosives dispersing 10 to 1,000 Ci
Large RDD:High explosive dispersing 1,000 to 10,000 Ci
Small Dirty Bomb (RDD): 2 Ci cesium source + 10 lb TNT
Inner Ring: One cancer death per 100 people due to remaining radiation(typical dose 25 cGy)
Middle Ring: One cancer death per 1,000 people due to remaining radiation(typical dose 2 cGy)
Outer Ring: One cancer death per 10,000 people due to remaining radiation(typical dose 0.2 cGy)EPA suggests decontamination
Intermediate RDD: 2,000 Ci of cesium chloride, from a seed irradiator, and 10 lb of Semtex
Inner Ring: One cancer death per 100 people due to residual contamination (typical dose 25 cGy)
Middle Ring: One cancer death per 1,000 people due to residual contamination (typical dose 2 cGy)
Outer Ring: One cancer death per 10,000 people due to residual contamination (typical dose 0.2 cGy)
Large RDD: 10,000 Ci cobalt source (food irradiator rod)
Inner Ring: Same radiation level as permanently closed zone around Chernobyl
Middle Ring: Same radiation level as permanently controlled zone around Chernobyl
Outer Ring: Same radiation level as periodically controlled zone around Chernobyl
Large RDD: 10,000 Ci cobalt source (food irradiator rod)
You need to be part of a radiation casualty
• Health providers
• Physicists
• Social workers / administrators
team
Immediate Medical Management Issues
Immediate Medical Management Issues
• Triage
• Decontamination
• Initial stabilization and treatment of life-threatening injury
• Health care provider health and safety
• Surge capacity: availability of staff (quantity and specialists), supplies, space
Almost all the individual presenting at ER / clinic will not have a measurable radiation exposure
• Goiânia– 99.8% of individuals at ER/clinic not contaminated
– 8% had “psychosomatic reactions which mimicked radiation exposure”
• Israel, attacked by Scud missiles during 1991 Gulf war– 51% of individuals at ER were “stress casualties”
The job of the radiation physicists
• Determining / documenting radioactivity levels, and radiation dose levels
• Collecting samples to document contamination
• Assisting in decontamination procedures
• Disposing of radioactive waste
Staff radiation protection
• Fundamental Principles - Time - Distance - Shielding
• Personnel Protective Equipment
• Contamination Control
ContaminatedWaste
Waste
Contamination Control
RadiationSurvey
HOTLINE
STEPOFFPAD
CO
NT
AM
INA
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D A
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AB
UF
FE
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ON
EC
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AN
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Radiation Survey
& Charting
ED Staff
Clean Gloves, Masks,Gowns, Booties
Separate Entrance
Trauma Room
Protecting Staff from Contamination
Use standard precautions Use standard precautions (N95 mask if available)(N95 mask if available)
Survey hands and Survey hands and clothing frequentlyclothing frequently
Replace contaminated Replace contaminated gloves or clothinggloves or clothing
Keep the work area free of Keep the work area free of contaminationcontamination
Pregnant Staff
• Pregnant staff should be reassigned
We need to be prepared for a radiological incident
• Facilities should plan in advance and include procedures in their Disaster Plan
Everyone needs training!
If there is a plan in place and staff are well trained, radiation exposure to staff should be very low
“When workers at Chernobyl who were in the reactor area at the time of the nuclear accident were decontaminated, the medical personal at the site received less than 10 mGy of radiation.”
Mettler & Voelz,New England Journal of Medicine, 346: 1554 (2002)
Patient Management - Priorities
• Standard medical triage is the highest priority – don’t delay givingcritical care because a patient is contaminated
• Radiation exposure and contamination aresecondary considerations
External Contamination
• Radioactive material (usually in the form of dust particles) on the body surface and / or clothing
• Radiation dose rate from contamination is usually low, but while it remains on the patient it will continue to expose the patient and staff
Patient Decontamination
• Remove and bag patient’s clothing and personal belongings (typically removes 80 - 90%
of contamination)
• Handle foreign objects with care until proven non-radioactive with survey meter
• Survey patient and collect samples
Decontamination Priorities
• Wounds
• Intact skin
• Change outer gloves frequently to minimize spread of contamination
Decontamination of Wounds
• Contaminated wounds:– Irrigate, gently scrub with surgical sponge– Debride surgically only as needed
• Contaminated thermal burns:
– Gently rinse
– Change dressings to remove additional contamination
• Avoid overly aggressive decontamination
• Change dressings frequently
Decontamination of Skin
• Use multiple gentle efforts
• Use soap & water
• Cut hair if necessary (do not shave)
• Use survey meter
Cease Patient Decontamination
• When decontamination efforts produce no significant reduction in contamination
• When the level of radiation of the contaminated area is less than about twice background
Removing internal contamination is more problematic
Internal contamination countermeasures?
• Potassium iodide blocks radioactive iodine from being absorbed in the thyroid.
• Very limited utility
Internal contamination countermeasures?
• Potassium iodide blocks radioactive iodine from being absorbed in the thyroid.
• Totally useless
Internal contamination countermeasures?
Traps cesium in the intestine, so that it can be passed out of the body in the stool rather than bere-absorbed
Recently approved by FDA
Only useful if the radioactive material is cesium
High-dose radiation syndromes
Time
Recovery
or death
Manifest
illness
Latentperiod
Prodromal
effects
Self Renewing Tissuese.g. lining of the G.I. tract
Stem-cell compartment
Differentiating compartment
Mature functioning cells
Prodromal Effects
• Symptoms to be expected at about 50% lethal dose:– Neuromuscular – Easy fatigability– Gastrointestinal – Anorexia, vomiting
• Additional symptoms to be expectedafter a supra-lethal dose:– Neuromuscular – Fever &
hypotension– Gastrointestinal – Immediate diarrhea
Gastrointestinal Syndrome
Results from whole-body exposure to >8 Gy.
Due to crypt cell depletion and sloughing off of intestinal villi
Symptoms include nausea, vomiting, prolonged
diarrhea, loss of appetite, lethargy, dehydration,emaciation, exhaustion
Symptoms start a few hours after exposure but, depending upon the dose, there is often a
latent period around day 2-6, at which time severe symptoms return
Death occurs in around 5-15 days.
Hematopoietic Syndrome
Results from whole-body exposure to 3 - 8 Gy.
Due to depletion of blood stem cells
Symptoms include all of GI syndrome: nausea, vomiting, diarrhea, with similar latent period
~ 3 weeks after exposure, chills, fatigue, skin hemorrhages, mouth ulceration, anemia, epilation
Death within ~60 days due to infections and fever (lymphocyte and granulocyte depression), or hemorrhage (platelet depletion)
Some individuals may be saved by antibiotics, platelet infusions, bone marrow transplants, or growth factors.
Treatment of Large Radiation Exposures
• Treat patients symptomatically
• Prevent and manage infections– Reverse isolation
– Assess for infection and thrombocytopenia
– Antibiotics
– Electrolytes
– Hematopoietic growth factors,
e.g., GM-CSF, G-CSF (Neupogen)
– Continued assessment and supportive care
Bottom Line
Medical centers in major cities need to be able to quickly assemble a competent team to cope with a radiation incident:
Physicists Emergency room specialists Radiation oncologist / radiologist Psychologists
Selected Further Information
CDC and OSHA have good starting websites:www.bt.cdc.gov/radiation/index.aspwww.osha.gov/SLTC/emergencypreparedness/rdd_tech.html
DocumentsAmerican College of Radiology:“Disaster Preparedness for Radiology Professionals” Download at www.acr.org/departments/educ/disaster_prep/dp_primer.html
National Council on Radiation Protection and Measurement Report No. 138, 2001“Management of Terrorist Events Involving Radioactive Material”
The real bottom line The threat of radiological terror is
real
Most scenarios will present primarily organizational challenges
The real bottom line The threat of radiological terror is
real
Most scenarios will present primarily organizational challenges
The answer: