Medical Effects

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Spark – half life equations

Amount left = Initial amount x (0.5) (number of half lives)

(number of half-lives = total time/time of one half-life)

The half life of plutonium-238 is 27.1 years. If the original sample contains 12 grams of Pu, then how much will remain after 145 years?

Handouts

Einstein’s letter to President Roosevelt

Song lyrics by ex-attorney, folk singer Fred Small about the laughable solution the government had to a nuclear castastrophe.

CHARACTERISTICS & MEDICAL

EFFECTS OF NUCLEAR WEAPONS

Spark

• What are the dangers of radiation and radioactive fallout?

• How/where should an atomic bomb be detonated to maximize blast intensity? Radiofallout exposure?

• What are the symptoms of radiation exposure?

Objectives

• Match the type of nuclear weapons burst with its description.

• Recognize the medical effects of thermal, blast, radiation and combined injuries.

• List the environmental consequences of thermal, blast and radiation.

Overview

• Types of Ionizing

Radiation

• Terms

• Types of Bursts

• Medical and

Environmental Effects of

Thermal Radiation

• Medical and

Environmental Effects of the Blast Wave

• Medical and

Environmental Effects of

Radiation:

• Medical effects of

Combined injuries

• Detection, Protection &

Patient

Decontamination

REFERENCE:

• Air Force Handbook 32-4014, USAF Ability to Survive and Operate Procedures in a

Nuclear, Biological, and Chemical (NBC)

Environment

TERMS

• Ionization

– The separation of an electrically neutral atom or molecule into electrically charged components termed an ion pair.

– This is accomplished by removal of one or more electrons from an atom or molecule, which then becomes a positively charged ion.

TERMS

• Ionizing Radiation

– A radioactive source which has gone through the ion process.

TYPES OF IONIZING RADIATION

Alpha Radiation: A particulate with a very short range (2 to 3 inches). Has low penetration power and will not penetrate skin. Primarily an inhalation or internal hazard. This is the most ionizing form of radiation.

TYPES OF IONIZING RADIATION

Beta: Particulate with a medium range approximately 26 ft. Medium penetration power. Will penetrate the skin and cause beta burns.

I-131 use in medicine

• A pheochromocytoma tumor is seen as a dark sphere in the center of the body (it is in the left adrenal gland). The image is by MIBG scintigraphy , showing the tumor by radiation from radioiodine in the MIBG.

TYPES OF IONIZING RADIATION

Gamma/x-ray: Electromagnetic Radiation has no charge. Very penetrating and absorbed by dense material i.e. lead.

Primarily a hazard to living tissue. Gamma and xray are identical.

TYPES OF IONIZING RADIATION

Neutron: A particulate that is very penetrating. Neutrons are required to initiate the fission process. Large quantities produced in a nuclear explosion. May cause some things to become radioactive.

TERMS

Nuclear Detonation - Occurs as a result of the unstable isotopes of uranium or plutonium interaction with itself, thus causing a chain reaction at the subatomic level. To achieve this reaction the uranium or plutonium must have critical mass.

TYPES OF BURSTS

Air Burst: Detonation at such a height that the expanding fireball does not touch the earth’s surface. Blast, Thermal, and Prompt radiation are maximized.

TYPES OF BURSTS

Surface Burst:

• Detonation at the surface of the land or water or at the height above the surface less than the radius of the fireball.

• Fireball must make contact with the surface.

• Maximizes fallout, and blast and thermal effects are reduced.

TYPES OF BURSTS

• Subsurface Burst:

– Detonation where the center of the weapon is located below the earth or water surface.

– No Thermal or Prompt radiation, but may be some local fallout if weapon vents to the surface.

• High Altitude Detonation

– Detonation at an altitude of above 100,000 feet.

– Specifically designed to cause an electromagnetic pulse (EMP).

ENERGY DISTRIBUTION

Blast - 50% of the energy

Thermal - 35 % of the energy

Radiation - 15% of the energy

– 10% - fallout or residual radiation

– 5% - prompt radiation which is gamma/neutron and occurs during the first 60 seconds

Medical and Environmental Effects of

Thermal Radiation:

• Characteristics: HOT!...millions of degrees

– Travels at the speed of light: 186,000 mps

– Travels in a straight line

– Has little penetration and is easily absorbed

– Emission time will increase with yield (larger the bomb the longer the emission)

Medical and Environmental Effects of

Thermal Radiation:

• Pulses:

– Light - First Thermal Pulse - Short range, little power, basically UV & X-ray radiation

– Heat - Second Thermal Pulse - Longer lasting, more energy, and longer range.

Medical and Environmental Effects of

Thermal Radiation:

Medical Effects:

– First Thermal Pulse - Flash blindness and retinal burns

– Second Thermal Pulse - Skin Burns

– Factors that Effect Burns:

• Length of exposure

• Percent of body exposed

• Amount of energy per unit area of body

Medical and Environmental Effects of Thermal Radiation:

• Boy exposed to thermal rays about 1.5 miles from the hypocenter. February 1946.

Medical and Environmental Effects of

Thermal Radiation:

Environmental Effects: Firestorms, burning buildings, and toxic gases

Medical and Environmental Effects of the Blast Wave:

Blast Wave: a wave of compressed air traveling at the speed of sound.

• Components:

– Static Overpressure: Crushing, squeezing force that surround objects. This can be measured in

PSI above atmospheric pressure.

– Dynamic winds - Gale force winds associated with blast wave. Causes damage by pushing, tumbling, or tearing apart.

Medical and Environmental Effects of the Blast Wave:

Medical Effects:

Primary/Direct: Static overpressure results form overpressure compression or decompression. Ex

Pneumothorax, air embolisms, ruptured organs.

Secondary/indirect - Dynamic gale force winds and flying objects

• Crushing injuries - debris falling on you

• Missile injuries - debris flying at you

• Translational Injuries - (with winds in excess of 250 mph) -

You become airborne.

Medical and Environmental Effects of the Blast Wave:

• Environmental

Effects: High winds and pressure knock things down.

Medical and Environmental Effects of

Radiation:

Prompt Radiation: Occurs within the first minute of detonation and consists of Gamma

(Electromagnetic) and Neutron

(Particulate)

Medical and Environmental Effects of

Radiation:

• Residual Radiation (Fallout):

Early Fallout: the fallout that retuns to earth during the first 24 hours after detonation. This is the MOST hazardous type of fallout.

Delayed Fallout: Experienced after the first 24 hours. Long term medical hazard due to long lived radioisotopes which get dispersed over large area.

Considered long term health hazard.

Comparison of Radiation Terms

U.S. unit SI unit Description

Curie (Ci) Becquerel (Bq) Amount of radioactivity produced by a given amount of a substance.

Formulas

1 Ci = 37 billion Bq

1 Bq = 1 particle emission per second rad Gray (Gy) Amount of radiation required to deposit a certain amount of energy in some substance.

1 Gy = 100 rad

1 rad = 100 erg/g rem = rad × Q

1 Sv = 100 rem rem

Roentgen

(R)

Sievert (Sv) Amount of radiation required to deposit a certain amount of energy in human tissue.

N/A Amount of radiation required to ionize a mass of air to a certain degree.

1 R = 0.93 rad

Medical and Environmental

Effects of Radiation (

Acute

):

• Acute Effects:

Early Fallout: Causes acute effects which are beta burns and Acute Radiation Syndrome (ARS) which is a condition caused by acute exposure to radiation

• 0-100 RAD Subcritical

• 400-500 RAD = LD 50

• > 1000 RAD = LD 99.

Effect

Blood count changes

Dose

50 rem

Vomiting (threshold) 100 rem

Mortality (threshold) 150 rem

LD

50/60

* (with minimal supportive care) 320 – 360 rem

LD

50/60

(with supportive medical treatment) 480 – 540 rem

100% mortality (with best available treatment) 800 rem

*

(Adapted from NCRP Report No. 98 "Guidance on Radiation Received in Space

Activities, NCRP, Bethesda, MD (1989))

The LD

50/60 is that dose at which 50%of the exposed population will die within 60 days.

Medical and Environmental

Effects of Radiation (

Acute

):

Stages of ARS:

– Prodomal - People getting sick

– Latent - A feeling of well being that lasts 14-21 days

– Acute - The patient get sick again

– Recovery - The patient gets better or dies

Medical and Environmental

Effects of Radiation (

Acute

):

• Body Systems are Affected in sequential

order:

– Hemopoetic System - Blood forming cells and bone marrow

– Digestive System

– Cardiovascular System

– CNS

Medical and Environmental

Effects of Radiation (

Chronic

):

Delayed Fallout causes chronic effects such as cancers, genetic mutations, and growth defects.

• Factors that Affect Severity:

– What was the radiation dose?

– How was the dose distributed (Whole body or small area)

– Length of time exposed

Medical and Environmental

Effects of Radiation

• Environmental Effects:

– fallout contamination of food & water

– Biological uptake of radiological chemicals

Medical effects of COMBINED injuries.

Combined blast, thermal and radiation effects are greater than individual effects...a

synergistic effect

• Prognosis worse if radiation is combined with thermal or blast or both

Detection, Protection & Patient

Decontamination

• Detected & Measured: ADM 300

• Remove fallout contamination by brushing, clothing removal, shower

• Vacuum with HEPA filter vacuum

• Risk to Medical Personnel

– Fallout on clothing/skin/wounds

– Inhalation (Alpha/Beta)

– Ingestion (Alpha/Beta)

http://www.ki4u.com/survive/index.htm#light

_and_heat

Summary

• Types of Ionizing

Radiation

• Terms

• Types of Bursts

• Medical and

Environmental Effects of

Thermal Radiation

• Medical and

Environmental Effects of the Blast Wave

• Medical and

Environmental Effects of

Radiation:

• Medical effects of

Combined injuries

• Detection, Protection &

Patient

Decontamination http://www.defconwarningsystem.com/docum ents/The%20Effects%20of%20Nuclear%20War.

pdf

http://www.atomicarchive.com/index.shtml

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